1 //===--- SemaChecking.cpp - Extra Semantic Checking -----------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements extra semantic analysis beyond what is enforced
11 // by the C type system.
13 //===----------------------------------------------------------------------===//
15 #include "clang/Sema/SemaInternal.h"
16 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/CharUnits.h"
18 #include "clang/AST/DeclCXX.h"
19 #include "clang/AST/DeclObjC.h"
20 #include "clang/AST/EvaluatedExprVisitor.h"
21 #include "clang/AST/Expr.h"
22 #include "clang/AST/ExprCXX.h"
23 #include "clang/AST/ExprObjC.h"
24 #include "clang/AST/StmtCXX.h"
25 #include "clang/AST/StmtObjC.h"
26 #include "clang/Analysis/Analyses/FormatString.h"
27 #include "clang/Basic/CharInfo.h"
28 #include "clang/Basic/TargetBuiltins.h"
29 #include "clang/Basic/TargetInfo.h"
30 #include "clang/Lex/Lexer.h" // TODO: Extract static functions to fix layering.
31 #include "clang/Sema/Initialization.h"
32 #include "clang/Sema/Lookup.h"
33 #include "clang/Sema/ScopeInfo.h"
34 #include "clang/Sema/Sema.h"
35 #include "llvm/ADT/STLExtras.h"
36 #include "llvm/ADT/SmallBitVector.h"
37 #include "llvm/ADT/SmallString.h"
38 #include "llvm/Support/ConvertUTF.h"
39 #include "llvm/Support/raw_ostream.h"
41 using namespace clang;
44 SourceLocation Sema::getLocationOfStringLiteralByte(const StringLiteral *SL,
45 unsigned ByteNo) const {
46 return SL->getLocationOfByte(ByteNo, getSourceManager(), LangOpts,
47 Context.getTargetInfo());
50 /// Checks that a call expression's argument count is the desired number.
51 /// This is useful when doing custom type-checking. Returns true on error.
52 static bool checkArgCount(Sema &S, CallExpr *call, unsigned desiredArgCount) {
53 unsigned argCount = call->getNumArgs();
54 if (argCount == desiredArgCount) return false;
56 if (argCount < desiredArgCount)
57 return S.Diag(call->getLocEnd(), diag::err_typecheck_call_too_few_args)
58 << 0 /*function call*/ << desiredArgCount << argCount
59 << call->getSourceRange();
61 // Highlight all the excess arguments.
62 SourceRange range(call->getArg(desiredArgCount)->getLocStart(),
63 call->getArg(argCount - 1)->getLocEnd());
65 return S.Diag(range.getBegin(), diag::err_typecheck_call_too_many_args)
66 << 0 /*function call*/ << desiredArgCount << argCount
67 << call->getArg(1)->getSourceRange();
70 /// Check that the first argument to __builtin_annotation is an integer
71 /// and the second argument is a non-wide string literal.
72 static bool SemaBuiltinAnnotation(Sema &S, CallExpr *TheCall) {
73 if (checkArgCount(S, TheCall, 2))
76 // First argument should be an integer.
77 Expr *ValArg = TheCall->getArg(0);
78 QualType Ty = ValArg->getType();
79 if (!Ty->isIntegerType()) {
80 S.Diag(ValArg->getLocStart(), diag::err_builtin_annotation_first_arg)
81 << ValArg->getSourceRange();
85 // Second argument should be a constant string.
86 Expr *StrArg = TheCall->getArg(1)->IgnoreParenCasts();
87 StringLiteral *Literal = dyn_cast<StringLiteral>(StrArg);
88 if (!Literal || !Literal->isAscii()) {
89 S.Diag(StrArg->getLocStart(), diag::err_builtin_annotation_second_arg)
90 << StrArg->getSourceRange();
98 /// Check that the argument to __builtin_addressof is a glvalue, and set the
99 /// result type to the corresponding pointer type.
100 static bool SemaBuiltinAddressof(Sema &S, CallExpr *TheCall) {
101 if (checkArgCount(S, TheCall, 1))
104 ExprResult Arg(TheCall->getArg(0));
105 QualType ResultType = S.CheckAddressOfOperand(Arg, TheCall->getLocStart());
106 if (ResultType.isNull())
109 TheCall->setArg(0, Arg.get());
110 TheCall->setType(ResultType);
114 static void SemaBuiltinMemChkCall(Sema &S, FunctionDecl *FDecl,
115 CallExpr *TheCall, unsigned SizeIdx,
116 unsigned DstSizeIdx) {
117 if (TheCall->getNumArgs() <= SizeIdx ||
118 TheCall->getNumArgs() <= DstSizeIdx)
121 const Expr *SizeArg = TheCall->getArg(SizeIdx);
122 const Expr *DstSizeArg = TheCall->getArg(DstSizeIdx);
124 llvm::APSInt Size, DstSize;
126 // find out if both sizes are known at compile time
127 if (!SizeArg->EvaluateAsInt(Size, S.Context) ||
128 !DstSizeArg->EvaluateAsInt(DstSize, S.Context))
131 if (Size.ule(DstSize))
134 // confirmed overflow so generate the diagnostic.
135 IdentifierInfo *FnName = FDecl->getIdentifier();
136 SourceLocation SL = TheCall->getLocStart();
137 SourceRange SR = TheCall->getSourceRange();
139 S.Diag(SL, diag::warn_memcpy_chk_overflow) << SR << FnName;
142 static bool SemaBuiltinCallWithStaticChain(Sema &S, CallExpr *BuiltinCall) {
143 if (checkArgCount(S, BuiltinCall, 2))
146 SourceLocation BuiltinLoc = BuiltinCall->getLocStart();
147 Expr *Builtin = BuiltinCall->getCallee()->IgnoreImpCasts();
148 Expr *Call = BuiltinCall->getArg(0);
149 Expr *Chain = BuiltinCall->getArg(1);
151 if (Call->getStmtClass() != Stmt::CallExprClass) {
152 S.Diag(BuiltinLoc, diag::err_first_argument_to_cwsc_not_call)
153 << Call->getSourceRange();
157 auto CE = cast<CallExpr>(Call);
158 if (CE->getCallee()->getType()->isBlockPointerType()) {
159 S.Diag(BuiltinLoc, diag::err_first_argument_to_cwsc_block_call)
160 << Call->getSourceRange();
164 const Decl *TargetDecl = CE->getCalleeDecl();
165 if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl))
166 if (FD->getBuiltinID()) {
167 S.Diag(BuiltinLoc, diag::err_first_argument_to_cwsc_builtin_call)
168 << Call->getSourceRange();
172 if (isa<CXXPseudoDestructorExpr>(CE->getCallee()->IgnoreParens())) {
173 S.Diag(BuiltinLoc, diag::err_first_argument_to_cwsc_pdtor_call)
174 << Call->getSourceRange();
178 ExprResult ChainResult = S.UsualUnaryConversions(Chain);
179 if (ChainResult.isInvalid())
181 if (!ChainResult.get()->getType()->isPointerType()) {
182 S.Diag(BuiltinLoc, diag::err_second_argument_to_cwsc_not_pointer)
183 << Chain->getSourceRange();
187 QualType ReturnTy = CE->getCallReturnType();
188 QualType ArgTys[2] = { ReturnTy, ChainResult.get()->getType() };
189 QualType BuiltinTy = S.Context.getFunctionType(
190 ReturnTy, ArgTys, FunctionProtoType::ExtProtoInfo());
191 QualType BuiltinPtrTy = S.Context.getPointerType(BuiltinTy);
194 S.ImpCastExprToType(Builtin, BuiltinPtrTy, CK_BuiltinFnToFnPtr).get();
196 BuiltinCall->setType(CE->getType());
197 BuiltinCall->setValueKind(CE->getValueKind());
198 BuiltinCall->setObjectKind(CE->getObjectKind());
199 BuiltinCall->setCallee(Builtin);
200 BuiltinCall->setArg(1, ChainResult.get());
206 Sema::CheckBuiltinFunctionCall(FunctionDecl *FDecl, unsigned BuiltinID,
208 ExprResult TheCallResult(TheCall);
210 // Find out if any arguments are required to be integer constant expressions.
211 unsigned ICEArguments = 0;
212 ASTContext::GetBuiltinTypeError Error;
213 Context.GetBuiltinType(BuiltinID, Error, &ICEArguments);
214 if (Error != ASTContext::GE_None)
215 ICEArguments = 0; // Don't diagnose previously diagnosed errors.
217 // If any arguments are required to be ICE's, check and diagnose.
218 for (unsigned ArgNo = 0; ICEArguments != 0; ++ArgNo) {
219 // Skip arguments not required to be ICE's.
220 if ((ICEArguments & (1 << ArgNo)) == 0) continue;
223 if (SemaBuiltinConstantArg(TheCall, ArgNo, Result))
225 ICEArguments &= ~(1 << ArgNo);
229 case Builtin::BI__builtin___CFStringMakeConstantString:
230 assert(TheCall->getNumArgs() == 1 &&
231 "Wrong # arguments to builtin CFStringMakeConstantString");
232 if (CheckObjCString(TheCall->getArg(0)))
235 case Builtin::BI__builtin_stdarg_start:
236 case Builtin::BI__builtin_va_start:
237 if (SemaBuiltinVAStart(TheCall))
240 case Builtin::BI__va_start: {
241 switch (Context.getTargetInfo().getTriple().getArch()) {
242 case llvm::Triple::arm:
243 case llvm::Triple::thumb:
244 if (SemaBuiltinVAStartARM(TheCall))
248 if (SemaBuiltinVAStart(TheCall))
254 case Builtin::BI__builtin_isgreater:
255 case Builtin::BI__builtin_isgreaterequal:
256 case Builtin::BI__builtin_isless:
257 case Builtin::BI__builtin_islessequal:
258 case Builtin::BI__builtin_islessgreater:
259 case Builtin::BI__builtin_isunordered:
260 if (SemaBuiltinUnorderedCompare(TheCall))
263 case Builtin::BI__builtin_fpclassify:
264 if (SemaBuiltinFPClassification(TheCall, 6))
267 case Builtin::BI__builtin_isfinite:
268 case Builtin::BI__builtin_isinf:
269 case Builtin::BI__builtin_isinf_sign:
270 case Builtin::BI__builtin_isnan:
271 case Builtin::BI__builtin_isnormal:
272 if (SemaBuiltinFPClassification(TheCall, 1))
275 case Builtin::BI__builtin_shufflevector:
276 return SemaBuiltinShuffleVector(TheCall);
277 // TheCall will be freed by the smart pointer here, but that's fine, since
278 // SemaBuiltinShuffleVector guts it, but then doesn't release it.
279 case Builtin::BI__builtin_prefetch:
280 if (SemaBuiltinPrefetch(TheCall))
283 case Builtin::BI__assume:
284 case Builtin::BI__builtin_assume:
285 if (SemaBuiltinAssume(TheCall))
288 case Builtin::BI__builtin_assume_aligned:
289 if (SemaBuiltinAssumeAligned(TheCall))
292 case Builtin::BI__builtin_object_size:
293 if (SemaBuiltinConstantArgRange(TheCall, 1, 0, 3))
296 case Builtin::BI__builtin_longjmp:
297 if (SemaBuiltinLongjmp(TheCall))
301 case Builtin::BI__builtin_classify_type:
302 if (checkArgCount(*this, TheCall, 1)) return true;
303 TheCall->setType(Context.IntTy);
305 case Builtin::BI__builtin_constant_p:
306 if (checkArgCount(*this, TheCall, 1)) return true;
307 TheCall->setType(Context.IntTy);
309 case Builtin::BI__sync_fetch_and_add:
310 case Builtin::BI__sync_fetch_and_add_1:
311 case Builtin::BI__sync_fetch_and_add_2:
312 case Builtin::BI__sync_fetch_and_add_4:
313 case Builtin::BI__sync_fetch_and_add_8:
314 case Builtin::BI__sync_fetch_and_add_16:
315 case Builtin::BI__sync_fetch_and_sub:
316 case Builtin::BI__sync_fetch_and_sub_1:
317 case Builtin::BI__sync_fetch_and_sub_2:
318 case Builtin::BI__sync_fetch_and_sub_4:
319 case Builtin::BI__sync_fetch_and_sub_8:
320 case Builtin::BI__sync_fetch_and_sub_16:
321 case Builtin::BI__sync_fetch_and_or:
322 case Builtin::BI__sync_fetch_and_or_1:
323 case Builtin::BI__sync_fetch_and_or_2:
324 case Builtin::BI__sync_fetch_and_or_4:
325 case Builtin::BI__sync_fetch_and_or_8:
326 case Builtin::BI__sync_fetch_and_or_16:
327 case Builtin::BI__sync_fetch_and_and:
328 case Builtin::BI__sync_fetch_and_and_1:
329 case Builtin::BI__sync_fetch_and_and_2:
330 case Builtin::BI__sync_fetch_and_and_4:
331 case Builtin::BI__sync_fetch_and_and_8:
332 case Builtin::BI__sync_fetch_and_and_16:
333 case Builtin::BI__sync_fetch_and_xor:
334 case Builtin::BI__sync_fetch_and_xor_1:
335 case Builtin::BI__sync_fetch_and_xor_2:
336 case Builtin::BI__sync_fetch_and_xor_4:
337 case Builtin::BI__sync_fetch_and_xor_8:
338 case Builtin::BI__sync_fetch_and_xor_16:
339 case Builtin::BI__sync_fetch_and_nand:
340 case Builtin::BI__sync_fetch_and_nand_1:
341 case Builtin::BI__sync_fetch_and_nand_2:
342 case Builtin::BI__sync_fetch_and_nand_4:
343 case Builtin::BI__sync_fetch_and_nand_8:
344 case Builtin::BI__sync_fetch_and_nand_16:
345 case Builtin::BI__sync_add_and_fetch:
346 case Builtin::BI__sync_add_and_fetch_1:
347 case Builtin::BI__sync_add_and_fetch_2:
348 case Builtin::BI__sync_add_and_fetch_4:
349 case Builtin::BI__sync_add_and_fetch_8:
350 case Builtin::BI__sync_add_and_fetch_16:
351 case Builtin::BI__sync_sub_and_fetch:
352 case Builtin::BI__sync_sub_and_fetch_1:
353 case Builtin::BI__sync_sub_and_fetch_2:
354 case Builtin::BI__sync_sub_and_fetch_4:
355 case Builtin::BI__sync_sub_and_fetch_8:
356 case Builtin::BI__sync_sub_and_fetch_16:
357 case Builtin::BI__sync_and_and_fetch:
358 case Builtin::BI__sync_and_and_fetch_1:
359 case Builtin::BI__sync_and_and_fetch_2:
360 case Builtin::BI__sync_and_and_fetch_4:
361 case Builtin::BI__sync_and_and_fetch_8:
362 case Builtin::BI__sync_and_and_fetch_16:
363 case Builtin::BI__sync_or_and_fetch:
364 case Builtin::BI__sync_or_and_fetch_1:
365 case Builtin::BI__sync_or_and_fetch_2:
366 case Builtin::BI__sync_or_and_fetch_4:
367 case Builtin::BI__sync_or_and_fetch_8:
368 case Builtin::BI__sync_or_and_fetch_16:
369 case Builtin::BI__sync_xor_and_fetch:
370 case Builtin::BI__sync_xor_and_fetch_1:
371 case Builtin::BI__sync_xor_and_fetch_2:
372 case Builtin::BI__sync_xor_and_fetch_4:
373 case Builtin::BI__sync_xor_and_fetch_8:
374 case Builtin::BI__sync_xor_and_fetch_16:
375 case Builtin::BI__sync_nand_and_fetch:
376 case Builtin::BI__sync_nand_and_fetch_1:
377 case Builtin::BI__sync_nand_and_fetch_2:
378 case Builtin::BI__sync_nand_and_fetch_4:
379 case Builtin::BI__sync_nand_and_fetch_8:
380 case Builtin::BI__sync_nand_and_fetch_16:
381 case Builtin::BI__sync_val_compare_and_swap:
382 case Builtin::BI__sync_val_compare_and_swap_1:
383 case Builtin::BI__sync_val_compare_and_swap_2:
384 case Builtin::BI__sync_val_compare_and_swap_4:
385 case Builtin::BI__sync_val_compare_and_swap_8:
386 case Builtin::BI__sync_val_compare_and_swap_16:
387 case Builtin::BI__sync_bool_compare_and_swap:
388 case Builtin::BI__sync_bool_compare_and_swap_1:
389 case Builtin::BI__sync_bool_compare_and_swap_2:
390 case Builtin::BI__sync_bool_compare_and_swap_4:
391 case Builtin::BI__sync_bool_compare_and_swap_8:
392 case Builtin::BI__sync_bool_compare_and_swap_16:
393 case Builtin::BI__sync_lock_test_and_set:
394 case Builtin::BI__sync_lock_test_and_set_1:
395 case Builtin::BI__sync_lock_test_and_set_2:
396 case Builtin::BI__sync_lock_test_and_set_4:
397 case Builtin::BI__sync_lock_test_and_set_8:
398 case Builtin::BI__sync_lock_test_and_set_16:
399 case Builtin::BI__sync_lock_release:
400 case Builtin::BI__sync_lock_release_1:
401 case Builtin::BI__sync_lock_release_2:
402 case Builtin::BI__sync_lock_release_4:
403 case Builtin::BI__sync_lock_release_8:
404 case Builtin::BI__sync_lock_release_16:
405 case Builtin::BI__sync_swap:
406 case Builtin::BI__sync_swap_1:
407 case Builtin::BI__sync_swap_2:
408 case Builtin::BI__sync_swap_4:
409 case Builtin::BI__sync_swap_8:
410 case Builtin::BI__sync_swap_16:
411 return SemaBuiltinAtomicOverloaded(TheCallResult);
412 #define BUILTIN(ID, TYPE, ATTRS)
413 #define ATOMIC_BUILTIN(ID, TYPE, ATTRS) \
414 case Builtin::BI##ID: \
415 return SemaAtomicOpsOverloaded(TheCallResult, AtomicExpr::AO##ID);
416 #include "clang/Basic/Builtins.def"
417 case Builtin::BI__builtin_annotation:
418 if (SemaBuiltinAnnotation(*this, TheCall))
421 case Builtin::BI__builtin_addressof:
422 if (SemaBuiltinAddressof(*this, TheCall))
425 case Builtin::BI__builtin_operator_new:
426 case Builtin::BI__builtin_operator_delete:
427 if (!getLangOpts().CPlusPlus) {
428 Diag(TheCall->getExprLoc(), diag::err_builtin_requires_language)
429 << (BuiltinID == Builtin::BI__builtin_operator_new
430 ? "__builtin_operator_new"
431 : "__builtin_operator_delete")
435 // CodeGen assumes it can find the global new and delete to call,
436 // so ensure that they are declared.
437 DeclareGlobalNewDelete();
440 // check secure string manipulation functions where overflows
441 // are detectable at compile time
442 case Builtin::BI__builtin___memcpy_chk:
443 case Builtin::BI__builtin___memmove_chk:
444 case Builtin::BI__builtin___memset_chk:
445 case Builtin::BI__builtin___strlcat_chk:
446 case Builtin::BI__builtin___strlcpy_chk:
447 case Builtin::BI__builtin___strncat_chk:
448 case Builtin::BI__builtin___strncpy_chk:
449 case Builtin::BI__builtin___stpncpy_chk:
450 SemaBuiltinMemChkCall(*this, FDecl, TheCall, 2, 3);
452 case Builtin::BI__builtin___memccpy_chk:
453 SemaBuiltinMemChkCall(*this, FDecl, TheCall, 3, 4);
455 case Builtin::BI__builtin___snprintf_chk:
456 case Builtin::BI__builtin___vsnprintf_chk:
457 SemaBuiltinMemChkCall(*this, FDecl, TheCall, 1, 3);
460 case Builtin::BI__builtin_call_with_static_chain:
461 if (SemaBuiltinCallWithStaticChain(*this, TheCall))
466 // Since the target specific builtins for each arch overlap, only check those
467 // of the arch we are compiling for.
468 if (BuiltinID >= Builtin::FirstTSBuiltin) {
469 switch (Context.getTargetInfo().getTriple().getArch()) {
470 case llvm::Triple::arm:
471 case llvm::Triple::armeb:
472 case llvm::Triple::thumb:
473 case llvm::Triple::thumbeb:
474 if (CheckARMBuiltinFunctionCall(BuiltinID, TheCall))
477 case llvm::Triple::aarch64:
478 case llvm::Triple::aarch64_be:
479 if (CheckAArch64BuiltinFunctionCall(BuiltinID, TheCall))
482 case llvm::Triple::mips:
483 case llvm::Triple::mipsel:
484 case llvm::Triple::mips64:
485 case llvm::Triple::mips64el:
486 if (CheckMipsBuiltinFunctionCall(BuiltinID, TheCall))
489 case llvm::Triple::x86:
490 case llvm::Triple::x86_64:
491 if (CheckX86BuiltinFunctionCall(BuiltinID, TheCall))
499 return TheCallResult;
502 // Get the valid immediate range for the specified NEON type code.
503 static unsigned RFT(unsigned t, bool shift = false, bool ForceQuad = false) {
504 NeonTypeFlags Type(t);
505 int IsQuad = ForceQuad ? true : Type.isQuad();
506 switch (Type.getEltType()) {
507 case NeonTypeFlags::Int8:
508 case NeonTypeFlags::Poly8:
509 return shift ? 7 : (8 << IsQuad) - 1;
510 case NeonTypeFlags::Int16:
511 case NeonTypeFlags::Poly16:
512 return shift ? 15 : (4 << IsQuad) - 1;
513 case NeonTypeFlags::Int32:
514 return shift ? 31 : (2 << IsQuad) - 1;
515 case NeonTypeFlags::Int64:
516 case NeonTypeFlags::Poly64:
517 return shift ? 63 : (1 << IsQuad) - 1;
518 case NeonTypeFlags::Poly128:
519 return shift ? 127 : (1 << IsQuad) - 1;
520 case NeonTypeFlags::Float16:
521 assert(!shift && "cannot shift float types!");
522 return (4 << IsQuad) - 1;
523 case NeonTypeFlags::Float32:
524 assert(!shift && "cannot shift float types!");
525 return (2 << IsQuad) - 1;
526 case NeonTypeFlags::Float64:
527 assert(!shift && "cannot shift float types!");
528 return (1 << IsQuad) - 1;
530 llvm_unreachable("Invalid NeonTypeFlag!");
533 /// getNeonEltType - Return the QualType corresponding to the elements of
534 /// the vector type specified by the NeonTypeFlags. This is used to check
535 /// the pointer arguments for Neon load/store intrinsics.
536 static QualType getNeonEltType(NeonTypeFlags Flags, ASTContext &Context,
537 bool IsPolyUnsigned, bool IsInt64Long) {
538 switch (Flags.getEltType()) {
539 case NeonTypeFlags::Int8:
540 return Flags.isUnsigned() ? Context.UnsignedCharTy : Context.SignedCharTy;
541 case NeonTypeFlags::Int16:
542 return Flags.isUnsigned() ? Context.UnsignedShortTy : Context.ShortTy;
543 case NeonTypeFlags::Int32:
544 return Flags.isUnsigned() ? Context.UnsignedIntTy : Context.IntTy;
545 case NeonTypeFlags::Int64:
547 return Flags.isUnsigned() ? Context.UnsignedLongTy : Context.LongTy;
549 return Flags.isUnsigned() ? Context.UnsignedLongLongTy
550 : Context.LongLongTy;
551 case NeonTypeFlags::Poly8:
552 return IsPolyUnsigned ? Context.UnsignedCharTy : Context.SignedCharTy;
553 case NeonTypeFlags::Poly16:
554 return IsPolyUnsigned ? Context.UnsignedShortTy : Context.ShortTy;
555 case NeonTypeFlags::Poly64:
556 return Context.UnsignedLongTy;
557 case NeonTypeFlags::Poly128:
559 case NeonTypeFlags::Float16:
560 return Context.HalfTy;
561 case NeonTypeFlags::Float32:
562 return Context.FloatTy;
563 case NeonTypeFlags::Float64:
564 return Context.DoubleTy;
566 llvm_unreachable("Invalid NeonTypeFlag!");
569 bool Sema::CheckNeonBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) {
574 bool HasConstPtr = false;
576 #define GET_NEON_OVERLOAD_CHECK
577 #include "clang/Basic/arm_neon.inc"
578 #undef GET_NEON_OVERLOAD_CHECK
581 // For NEON intrinsics which are overloaded on vector element type, validate
582 // the immediate which specifies which variant to emit.
583 unsigned ImmArg = TheCall->getNumArgs()-1;
585 if (SemaBuiltinConstantArg(TheCall, ImmArg, Result))
588 TV = Result.getLimitedValue(64);
589 if ((TV > 63) || (mask & (1ULL << TV)) == 0)
590 return Diag(TheCall->getLocStart(), diag::err_invalid_neon_type_code)
591 << TheCall->getArg(ImmArg)->getSourceRange();
594 if (PtrArgNum >= 0) {
595 // Check that pointer arguments have the specified type.
596 Expr *Arg = TheCall->getArg(PtrArgNum);
597 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Arg))
598 Arg = ICE->getSubExpr();
599 ExprResult RHS = DefaultFunctionArrayLvalueConversion(Arg);
600 QualType RHSTy = RHS.get()->getType();
602 llvm::Triple::ArchType Arch = Context.getTargetInfo().getTriple().getArch();
603 bool IsPolyUnsigned = Arch == llvm::Triple::aarch64;
605 Context.getTargetInfo().getInt64Type() == TargetInfo::SignedLong;
607 getNeonEltType(NeonTypeFlags(TV), Context, IsPolyUnsigned, IsInt64Long);
609 EltTy = EltTy.withConst();
610 QualType LHSTy = Context.getPointerType(EltTy);
611 AssignConvertType ConvTy;
612 ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS);
615 if (DiagnoseAssignmentResult(ConvTy, Arg->getLocStart(), LHSTy, RHSTy,
616 RHS.get(), AA_Assigning))
620 // For NEON intrinsics which take an immediate value as part of the
621 // instruction, range check them here.
622 unsigned i = 0, l = 0, u = 0;
626 #define GET_NEON_IMMEDIATE_CHECK
627 #include "clang/Basic/arm_neon.inc"
628 #undef GET_NEON_IMMEDIATE_CHECK
631 return SemaBuiltinConstantArgRange(TheCall, i, l, u + l);
634 bool Sema::CheckARMBuiltinExclusiveCall(unsigned BuiltinID, CallExpr *TheCall,
636 assert((BuiltinID == ARM::BI__builtin_arm_ldrex ||
637 BuiltinID == ARM::BI__builtin_arm_ldaex ||
638 BuiltinID == ARM::BI__builtin_arm_strex ||
639 BuiltinID == ARM::BI__builtin_arm_stlex ||
640 BuiltinID == AArch64::BI__builtin_arm_ldrex ||
641 BuiltinID == AArch64::BI__builtin_arm_ldaex ||
642 BuiltinID == AArch64::BI__builtin_arm_strex ||
643 BuiltinID == AArch64::BI__builtin_arm_stlex) &&
644 "unexpected ARM builtin");
645 bool IsLdrex = BuiltinID == ARM::BI__builtin_arm_ldrex ||
646 BuiltinID == ARM::BI__builtin_arm_ldaex ||
647 BuiltinID == AArch64::BI__builtin_arm_ldrex ||
648 BuiltinID == AArch64::BI__builtin_arm_ldaex;
650 DeclRefExpr *DRE =cast<DeclRefExpr>(TheCall->getCallee()->IgnoreParenCasts());
652 // Ensure that we have the proper number of arguments.
653 if (checkArgCount(*this, TheCall, IsLdrex ? 1 : 2))
656 // Inspect the pointer argument of the atomic builtin. This should always be
657 // a pointer type, whose element is an integral scalar or pointer type.
658 // Because it is a pointer type, we don't have to worry about any implicit
660 Expr *PointerArg = TheCall->getArg(IsLdrex ? 0 : 1);
661 ExprResult PointerArgRes = DefaultFunctionArrayLvalueConversion(PointerArg);
662 if (PointerArgRes.isInvalid())
664 PointerArg = PointerArgRes.get();
666 const PointerType *pointerType = PointerArg->getType()->getAs<PointerType>();
668 Diag(DRE->getLocStart(), diag::err_atomic_builtin_must_be_pointer)
669 << PointerArg->getType() << PointerArg->getSourceRange();
673 // ldrex takes a "const volatile T*" and strex takes a "volatile T*". Our next
674 // task is to insert the appropriate casts into the AST. First work out just
675 // what the appropriate type is.
676 QualType ValType = pointerType->getPointeeType();
677 QualType AddrType = ValType.getUnqualifiedType().withVolatile();
681 // Issue a warning if the cast is dodgy.
682 CastKind CastNeeded = CK_NoOp;
683 if (!AddrType.isAtLeastAsQualifiedAs(ValType)) {
684 CastNeeded = CK_BitCast;
685 Diag(DRE->getLocStart(), diag::ext_typecheck_convert_discards_qualifiers)
686 << PointerArg->getType()
687 << Context.getPointerType(AddrType)
688 << AA_Passing << PointerArg->getSourceRange();
691 // Finally, do the cast and replace the argument with the corrected version.
692 AddrType = Context.getPointerType(AddrType);
693 PointerArgRes = ImpCastExprToType(PointerArg, AddrType, CastNeeded);
694 if (PointerArgRes.isInvalid())
696 PointerArg = PointerArgRes.get();
698 TheCall->setArg(IsLdrex ? 0 : 1, PointerArg);
700 // In general, we allow ints, floats and pointers to be loaded and stored.
701 if (!ValType->isIntegerType() && !ValType->isAnyPointerType() &&
702 !ValType->isBlockPointerType() && !ValType->isFloatingType()) {
703 Diag(DRE->getLocStart(), diag::err_atomic_builtin_must_be_pointer_intfltptr)
704 << PointerArg->getType() << PointerArg->getSourceRange();
708 // But ARM doesn't have instructions to deal with 128-bit versions.
709 if (Context.getTypeSize(ValType) > MaxWidth) {
710 assert(MaxWidth == 64 && "Diagnostic unexpectedly inaccurate");
711 Diag(DRE->getLocStart(), diag::err_atomic_exclusive_builtin_pointer_size)
712 << PointerArg->getType() << PointerArg->getSourceRange();
716 switch (ValType.getObjCLifetime()) {
717 case Qualifiers::OCL_None:
718 case Qualifiers::OCL_ExplicitNone:
722 case Qualifiers::OCL_Weak:
723 case Qualifiers::OCL_Strong:
724 case Qualifiers::OCL_Autoreleasing:
725 Diag(DRE->getLocStart(), diag::err_arc_atomic_ownership)
726 << ValType << PointerArg->getSourceRange();
732 TheCall->setType(ValType);
736 // Initialize the argument to be stored.
737 ExprResult ValArg = TheCall->getArg(0);
738 InitializedEntity Entity = InitializedEntity::InitializeParameter(
739 Context, ValType, /*consume*/ false);
740 ValArg = PerformCopyInitialization(Entity, SourceLocation(), ValArg);
741 if (ValArg.isInvalid())
743 TheCall->setArg(0, ValArg.get());
745 // __builtin_arm_strex always returns an int. It's marked as such in the .def,
746 // but the custom checker bypasses all default analysis.
747 TheCall->setType(Context.IntTy);
751 bool Sema::CheckARMBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) {
754 if (BuiltinID == ARM::BI__builtin_arm_ldrex ||
755 BuiltinID == ARM::BI__builtin_arm_ldaex ||
756 BuiltinID == ARM::BI__builtin_arm_strex ||
757 BuiltinID == ARM::BI__builtin_arm_stlex) {
758 return CheckARMBuiltinExclusiveCall(BuiltinID, TheCall, 64);
761 if (BuiltinID == ARM::BI__builtin_arm_prefetch) {
762 return SemaBuiltinConstantArgRange(TheCall, 1, 0, 1) ||
763 SemaBuiltinConstantArgRange(TheCall, 2, 0, 1);
766 if (CheckNeonBuiltinFunctionCall(BuiltinID, TheCall))
769 // For intrinsics which take an immediate value as part of the instruction,
770 // range check them here.
771 unsigned i = 0, l = 0, u = 0;
773 default: return false;
774 case ARM::BI__builtin_arm_ssat: i = 1; l = 1; u = 31; break;
775 case ARM::BI__builtin_arm_usat: i = 1; u = 31; break;
776 case ARM::BI__builtin_arm_vcvtr_f:
777 case ARM::BI__builtin_arm_vcvtr_d: i = 1; u = 1; break;
778 case ARM::BI__builtin_arm_dmb:
779 case ARM::BI__builtin_arm_dsb:
780 case ARM::BI__builtin_arm_isb:
781 case ARM::BI__builtin_arm_dbg: l = 0; u = 15; break;
784 // FIXME: VFP Intrinsics should error if VFP not present.
785 return SemaBuiltinConstantArgRange(TheCall, i, l, u + l);
788 bool Sema::CheckAArch64BuiltinFunctionCall(unsigned BuiltinID,
792 if (BuiltinID == AArch64::BI__builtin_arm_ldrex ||
793 BuiltinID == AArch64::BI__builtin_arm_ldaex ||
794 BuiltinID == AArch64::BI__builtin_arm_strex ||
795 BuiltinID == AArch64::BI__builtin_arm_stlex) {
796 return CheckARMBuiltinExclusiveCall(BuiltinID, TheCall, 128);
799 if (BuiltinID == AArch64::BI__builtin_arm_prefetch) {
800 return SemaBuiltinConstantArgRange(TheCall, 1, 0, 1) ||
801 SemaBuiltinConstantArgRange(TheCall, 2, 0, 2) ||
802 SemaBuiltinConstantArgRange(TheCall, 3, 0, 1) ||
803 SemaBuiltinConstantArgRange(TheCall, 4, 0, 1);
806 if (CheckNeonBuiltinFunctionCall(BuiltinID, TheCall))
809 // For intrinsics which take an immediate value as part of the instruction,
810 // range check them here.
811 unsigned i = 0, l = 0, u = 0;
813 default: return false;
814 case AArch64::BI__builtin_arm_dmb:
815 case AArch64::BI__builtin_arm_dsb:
816 case AArch64::BI__builtin_arm_isb: l = 0; u = 15; break;
819 return SemaBuiltinConstantArgRange(TheCall, i, l, u + l);
822 bool Sema::CheckMipsBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) {
823 unsigned i = 0, l = 0, u = 0;
825 default: return false;
826 case Mips::BI__builtin_mips_wrdsp: i = 1; l = 0; u = 63; break;
827 case Mips::BI__builtin_mips_rddsp: i = 0; l = 0; u = 63; break;
828 case Mips::BI__builtin_mips_append: i = 2; l = 0; u = 31; break;
829 case Mips::BI__builtin_mips_balign: i = 2; l = 0; u = 3; break;
830 case Mips::BI__builtin_mips_precr_sra_ph_w: i = 2; l = 0; u = 31; break;
831 case Mips::BI__builtin_mips_precr_sra_r_ph_w: i = 2; l = 0; u = 31; break;
832 case Mips::BI__builtin_mips_prepend: i = 2; l = 0; u = 31; break;
835 return SemaBuiltinConstantArgRange(TheCall, i, l, u);
838 bool Sema::CheckX86BuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) {
839 unsigned i = 0, l = 0, u = 0;
841 default: return false;
842 case X86::BI_mm_prefetch: i = 1; l = 0; u = 3; break;
843 case X86::BI__builtin_ia32_cmpps:
844 case X86::BI__builtin_ia32_cmpss:
845 case X86::BI__builtin_ia32_cmppd:
846 case X86::BI__builtin_ia32_cmpsd: i = 2; l = 0; u = 31; break;
848 return SemaBuiltinConstantArgRange(TheCall, i, l, u);
851 /// Given a FunctionDecl's FormatAttr, attempts to populate the FomatStringInfo
852 /// parameter with the FormatAttr's correct format_idx and firstDataArg.
853 /// Returns true when the format fits the function and the FormatStringInfo has
855 bool Sema::getFormatStringInfo(const FormatAttr *Format, bool IsCXXMember,
856 FormatStringInfo *FSI) {
857 FSI->HasVAListArg = Format->getFirstArg() == 0;
858 FSI->FormatIdx = Format->getFormatIdx() - 1;
859 FSI->FirstDataArg = FSI->HasVAListArg ? 0 : Format->getFirstArg() - 1;
861 // The way the format attribute works in GCC, the implicit this argument
862 // of member functions is counted. However, it doesn't appear in our own
863 // lists, so decrement format_idx in that case.
865 if(FSI->FormatIdx == 0)
868 if (FSI->FirstDataArg != 0)
874 /// Checks if a the given expression evaluates to null.
876 /// \brief Returns true if the value evaluates to null.
877 static bool CheckNonNullExpr(Sema &S,
879 // As a special case, transparent unions initialized with zero are
880 // considered null for the purposes of the nonnull attribute.
881 if (const RecordType *UT = Expr->getType()->getAsUnionType()) {
882 if (UT->getDecl()->hasAttr<TransparentUnionAttr>())
883 if (const CompoundLiteralExpr *CLE =
884 dyn_cast<CompoundLiteralExpr>(Expr))
885 if (const InitListExpr *ILE =
886 dyn_cast<InitListExpr>(CLE->getInitializer()))
887 Expr = ILE->getInit(0);
891 return (!Expr->isValueDependent() &&
892 Expr->EvaluateAsBooleanCondition(Result, S.Context) &&
896 static void CheckNonNullArgument(Sema &S,
898 SourceLocation CallSiteLoc) {
899 if (CheckNonNullExpr(S, ArgExpr))
900 S.Diag(CallSiteLoc, diag::warn_null_arg) << ArgExpr->getSourceRange();
903 bool Sema::GetFormatNSStringIdx(const FormatAttr *Format, unsigned &Idx) {
904 FormatStringInfo FSI;
905 if ((GetFormatStringType(Format) == FST_NSString) &&
906 getFormatStringInfo(Format, false, &FSI)) {
912 /// \brief Diagnose use of %s directive in an NSString which is being passed
913 /// as formatting string to formatting method.
915 DiagnoseCStringFormatDirectiveInCFAPI(Sema &S,
916 const NamedDecl *FDecl,
921 ObjCStringFormatFamily SFFamily = FDecl->getObjCFStringFormattingFamily();
922 if (SFFamily == ObjCStringFormatFamily::SFF_CFString) {
927 for (const auto *I : FDecl->specific_attrs<FormatAttr>()) {
928 if (S.GetFormatNSStringIdx(I, Idx)) {
933 if (!Format || NumArgs <= Idx)
935 const Expr *FormatExpr = Args[Idx];
936 if (const CStyleCastExpr *CSCE = dyn_cast<CStyleCastExpr>(FormatExpr))
937 FormatExpr = CSCE->getSubExpr();
938 const StringLiteral *FormatString;
939 if (const ObjCStringLiteral *OSL =
940 dyn_cast<ObjCStringLiteral>(FormatExpr->IgnoreParenImpCasts()))
941 FormatString = OSL->getString();
943 FormatString = dyn_cast<StringLiteral>(FormatExpr->IgnoreParenImpCasts());
946 if (S.FormatStringHasSArg(FormatString)) {
947 S.Diag(FormatExpr->getExprLoc(), diag::warn_objc_cdirective_format_string)
949 S.Diag(FDecl->getLocation(), diag::note_entity_declared_at)
950 << FDecl->getDeclName();
954 static void CheckNonNullArguments(Sema &S,
955 const NamedDecl *FDecl,
956 ArrayRef<const Expr *> Args,
957 SourceLocation CallSiteLoc) {
958 // Check the attributes attached to the method/function itself.
959 llvm::SmallBitVector NonNullArgs;
960 for (const auto *NonNull : FDecl->specific_attrs<NonNullAttr>()) {
961 if (!NonNull->args_size()) {
962 // Easy case: all pointer arguments are nonnull.
963 for (const auto *Arg : Args)
964 if (S.isValidPointerAttrType(Arg->getType()))
965 CheckNonNullArgument(S, Arg, CallSiteLoc);
969 for (unsigned Val : NonNull->args()) {
970 if (Val >= Args.size())
972 if (NonNullArgs.empty())
973 NonNullArgs.resize(Args.size());
974 NonNullArgs.set(Val);
978 // Check the attributes on the parameters.
979 ArrayRef<ParmVarDecl*> parms;
980 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(FDecl))
981 parms = FD->parameters();
982 else if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(FDecl))
983 parms = MD->parameters();
985 unsigned ArgIndex = 0;
986 for (ArrayRef<ParmVarDecl*>::iterator I = parms.begin(), E = parms.end();
987 I != E; ++I, ++ArgIndex) {
988 const ParmVarDecl *PVD = *I;
989 if (PVD->hasAttr<NonNullAttr>() ||
990 (ArgIndex < NonNullArgs.size() && NonNullArgs[ArgIndex]))
991 CheckNonNullArgument(S, Args[ArgIndex], CallSiteLoc);
994 // In case this is a variadic call, check any remaining arguments.
995 for (/**/; ArgIndex < NonNullArgs.size(); ++ArgIndex)
996 if (NonNullArgs[ArgIndex])
997 CheckNonNullArgument(S, Args[ArgIndex], CallSiteLoc);
1000 /// Handles the checks for format strings, non-POD arguments to vararg
1001 /// functions, and NULL arguments passed to non-NULL parameters.
1002 void Sema::checkCall(NamedDecl *FDecl, ArrayRef<const Expr *> Args,
1003 unsigned NumParams, bool IsMemberFunction,
1004 SourceLocation Loc, SourceRange Range,
1005 VariadicCallType CallType) {
1006 // FIXME: We should check as much as we can in the template definition.
1007 if (CurContext->isDependentContext())
1010 // Printf and scanf checking.
1011 llvm::SmallBitVector CheckedVarArgs;
1013 for (const auto *I : FDecl->specific_attrs<FormatAttr>()) {
1014 // Only create vector if there are format attributes.
1015 CheckedVarArgs.resize(Args.size());
1017 CheckFormatArguments(I, Args, IsMemberFunction, CallType, Loc, Range,
1022 // Refuse POD arguments that weren't caught by the format string
1024 if (CallType != VariadicDoesNotApply) {
1025 for (unsigned ArgIdx = NumParams; ArgIdx < Args.size(); ++ArgIdx) {
1026 // Args[ArgIdx] can be null in malformed code.
1027 if (const Expr *Arg = Args[ArgIdx]) {
1028 if (CheckedVarArgs.empty() || !CheckedVarArgs[ArgIdx])
1029 checkVariadicArgument(Arg, CallType);
1035 CheckNonNullArguments(*this, FDecl, Args, Loc);
1037 // Type safety checking.
1038 for (const auto *I : FDecl->specific_attrs<ArgumentWithTypeTagAttr>())
1039 CheckArgumentWithTypeTag(I, Args.data());
1043 /// CheckConstructorCall - Check a constructor call for correctness and safety
1044 /// properties not enforced by the C type system.
1045 void Sema::CheckConstructorCall(FunctionDecl *FDecl,
1046 ArrayRef<const Expr *> Args,
1047 const FunctionProtoType *Proto,
1048 SourceLocation Loc) {
1049 VariadicCallType CallType =
1050 Proto->isVariadic() ? VariadicConstructor : VariadicDoesNotApply;
1051 checkCall(FDecl, Args, Proto->getNumParams(),
1052 /*IsMemberFunction=*/true, Loc, SourceRange(), CallType);
1055 /// CheckFunctionCall - Check a direct function call for various correctness
1056 /// and safety properties not strictly enforced by the C type system.
1057 bool Sema::CheckFunctionCall(FunctionDecl *FDecl, CallExpr *TheCall,
1058 const FunctionProtoType *Proto) {
1059 bool IsMemberOperatorCall = isa<CXXOperatorCallExpr>(TheCall) &&
1060 isa<CXXMethodDecl>(FDecl);
1061 bool IsMemberFunction = isa<CXXMemberCallExpr>(TheCall) ||
1062 IsMemberOperatorCall;
1063 VariadicCallType CallType = getVariadicCallType(FDecl, Proto,
1064 TheCall->getCallee());
1065 unsigned NumParams = Proto ? Proto->getNumParams() : 0;
1066 Expr** Args = TheCall->getArgs();
1067 unsigned NumArgs = TheCall->getNumArgs();
1068 if (IsMemberOperatorCall) {
1069 // If this is a call to a member operator, hide the first argument
1071 // FIXME: Our choice of AST representation here is less than ideal.
1075 checkCall(FDecl, llvm::makeArrayRef(Args, NumArgs), NumParams,
1076 IsMemberFunction, TheCall->getRParenLoc(),
1077 TheCall->getCallee()->getSourceRange(), CallType);
1079 IdentifierInfo *FnInfo = FDecl->getIdentifier();
1080 // None of the checks below are needed for functions that don't have
1081 // simple names (e.g., C++ conversion functions).
1085 CheckAbsoluteValueFunction(TheCall, FDecl, FnInfo);
1086 if (getLangOpts().ObjC1)
1087 DiagnoseCStringFormatDirectiveInCFAPI(*this, FDecl, Args, NumArgs);
1089 unsigned CMId = FDecl->getMemoryFunctionKind();
1093 // Handle memory setting and copying functions.
1094 if (CMId == Builtin::BIstrlcpy || CMId == Builtin::BIstrlcat)
1095 CheckStrlcpycatArguments(TheCall, FnInfo);
1096 else if (CMId == Builtin::BIstrncat)
1097 CheckStrncatArguments(TheCall, FnInfo);
1099 CheckMemaccessArguments(TheCall, CMId, FnInfo);
1104 bool Sema::CheckObjCMethodCall(ObjCMethodDecl *Method, SourceLocation lbrac,
1105 ArrayRef<const Expr *> Args) {
1106 VariadicCallType CallType =
1107 Method->isVariadic() ? VariadicMethod : VariadicDoesNotApply;
1109 checkCall(Method, Args, Method->param_size(),
1110 /*IsMemberFunction=*/false,
1111 lbrac, Method->getSourceRange(), CallType);
1116 bool Sema::CheckPointerCall(NamedDecl *NDecl, CallExpr *TheCall,
1117 const FunctionProtoType *Proto) {
1118 const VarDecl *V = dyn_cast<VarDecl>(NDecl);
1122 QualType Ty = V->getType();
1123 if (!Ty->isBlockPointerType() && !Ty->isFunctionPointerType())
1126 VariadicCallType CallType;
1127 if (!Proto || !Proto->isVariadic()) {
1128 CallType = VariadicDoesNotApply;
1129 } else if (Ty->isBlockPointerType()) {
1130 CallType = VariadicBlock;
1131 } else { // Ty->isFunctionPointerType()
1132 CallType = VariadicFunction;
1134 unsigned NumParams = Proto ? Proto->getNumParams() : 0;
1136 checkCall(NDecl, llvm::makeArrayRef(TheCall->getArgs(),
1137 TheCall->getNumArgs()),
1138 NumParams, /*IsMemberFunction=*/false, TheCall->getRParenLoc(),
1139 TheCall->getCallee()->getSourceRange(), CallType);
1144 /// Checks function calls when a FunctionDecl or a NamedDecl is not available,
1145 /// such as function pointers returned from functions.
1146 bool Sema::CheckOtherCall(CallExpr *TheCall, const FunctionProtoType *Proto) {
1147 VariadicCallType CallType = getVariadicCallType(/*FDecl=*/nullptr, Proto,
1148 TheCall->getCallee());
1149 unsigned NumParams = Proto ? Proto->getNumParams() : 0;
1151 checkCall(/*FDecl=*/nullptr,
1152 llvm::makeArrayRef(TheCall->getArgs(), TheCall->getNumArgs()),
1153 NumParams, /*IsMemberFunction=*/false, TheCall->getRParenLoc(),
1154 TheCall->getCallee()->getSourceRange(), CallType);
1159 static bool isValidOrderingForOp(int64_t Ordering, AtomicExpr::AtomicOp Op) {
1160 if (Ordering < AtomicExpr::AO_ABI_memory_order_relaxed ||
1161 Ordering > AtomicExpr::AO_ABI_memory_order_seq_cst)
1165 case AtomicExpr::AO__c11_atomic_init:
1166 llvm_unreachable("There is no ordering argument for an init");
1168 case AtomicExpr::AO__c11_atomic_load:
1169 case AtomicExpr::AO__atomic_load_n:
1170 case AtomicExpr::AO__atomic_load:
1171 return Ordering != AtomicExpr::AO_ABI_memory_order_release &&
1172 Ordering != AtomicExpr::AO_ABI_memory_order_acq_rel;
1174 case AtomicExpr::AO__c11_atomic_store:
1175 case AtomicExpr::AO__atomic_store:
1176 case AtomicExpr::AO__atomic_store_n:
1177 return Ordering != AtomicExpr::AO_ABI_memory_order_consume &&
1178 Ordering != AtomicExpr::AO_ABI_memory_order_acquire &&
1179 Ordering != AtomicExpr::AO_ABI_memory_order_acq_rel;
1186 ExprResult Sema::SemaAtomicOpsOverloaded(ExprResult TheCallResult,
1187 AtomicExpr::AtomicOp Op) {
1188 CallExpr *TheCall = cast<CallExpr>(TheCallResult.get());
1189 DeclRefExpr *DRE =cast<DeclRefExpr>(TheCall->getCallee()->IgnoreParenCasts());
1191 // All these operations take one of the following forms:
1193 // C __c11_atomic_init(A *, C)
1195 // C __c11_atomic_load(A *, int)
1197 // void __atomic_load(A *, CP, int)
1199 // C __c11_atomic_add(A *, M, int)
1201 // C __atomic_exchange_n(A *, CP, int)
1203 // void __atomic_exchange(A *, C *, CP, int)
1205 // bool __c11_atomic_compare_exchange_strong(A *, C *, CP, int, int)
1207 // bool __atomic_compare_exchange(A *, C *, CP, bool, int, int)
1210 const unsigned NumArgs[] = { 2, 2, 3, 3, 3, 4, 5, 6 };
1211 const unsigned NumVals[] = { 1, 0, 1, 1, 1, 2, 2, 3 };
1213 // C is an appropriate type,
1214 // A is volatile _Atomic(C) for __c11 builtins and is C for GNU builtins,
1215 // CP is C for __c11 builtins and GNU _n builtins and is C * otherwise,
1216 // M is C if C is an integer, and ptrdiff_t if C is a pointer, and
1217 // the int parameters are for orderings.
1219 assert(AtomicExpr::AO__c11_atomic_init == 0 &&
1220 AtomicExpr::AO__c11_atomic_fetch_xor + 1 == AtomicExpr::AO__atomic_load
1221 && "need to update code for modified C11 atomics");
1222 bool IsC11 = Op >= AtomicExpr::AO__c11_atomic_init &&
1223 Op <= AtomicExpr::AO__c11_atomic_fetch_xor;
1224 bool IsN = Op == AtomicExpr::AO__atomic_load_n ||
1225 Op == AtomicExpr::AO__atomic_store_n ||
1226 Op == AtomicExpr::AO__atomic_exchange_n ||
1227 Op == AtomicExpr::AO__atomic_compare_exchange_n;
1228 bool IsAddSub = false;
1231 case AtomicExpr::AO__c11_atomic_init:
1235 case AtomicExpr::AO__c11_atomic_load:
1236 case AtomicExpr::AO__atomic_load_n:
1240 case AtomicExpr::AO__c11_atomic_store:
1241 case AtomicExpr::AO__atomic_load:
1242 case AtomicExpr::AO__atomic_store:
1243 case AtomicExpr::AO__atomic_store_n:
1247 case AtomicExpr::AO__c11_atomic_fetch_add:
1248 case AtomicExpr::AO__c11_atomic_fetch_sub:
1249 case AtomicExpr::AO__atomic_fetch_add:
1250 case AtomicExpr::AO__atomic_fetch_sub:
1251 case AtomicExpr::AO__atomic_add_fetch:
1252 case AtomicExpr::AO__atomic_sub_fetch:
1255 case AtomicExpr::AO__c11_atomic_fetch_and:
1256 case AtomicExpr::AO__c11_atomic_fetch_or:
1257 case AtomicExpr::AO__c11_atomic_fetch_xor:
1258 case AtomicExpr::AO__atomic_fetch_and:
1259 case AtomicExpr::AO__atomic_fetch_or:
1260 case AtomicExpr::AO__atomic_fetch_xor:
1261 case AtomicExpr::AO__atomic_fetch_nand:
1262 case AtomicExpr::AO__atomic_and_fetch:
1263 case AtomicExpr::AO__atomic_or_fetch:
1264 case AtomicExpr::AO__atomic_xor_fetch:
1265 case AtomicExpr::AO__atomic_nand_fetch:
1269 case AtomicExpr::AO__c11_atomic_exchange:
1270 case AtomicExpr::AO__atomic_exchange_n:
1274 case AtomicExpr::AO__atomic_exchange:
1278 case AtomicExpr::AO__c11_atomic_compare_exchange_strong:
1279 case AtomicExpr::AO__c11_atomic_compare_exchange_weak:
1283 case AtomicExpr::AO__atomic_compare_exchange:
1284 case AtomicExpr::AO__atomic_compare_exchange_n:
1289 // Check we have the right number of arguments.
1290 if (TheCall->getNumArgs() < NumArgs[Form]) {
1291 Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args)
1292 << 0 << NumArgs[Form] << TheCall->getNumArgs()
1293 << TheCall->getCallee()->getSourceRange();
1295 } else if (TheCall->getNumArgs() > NumArgs[Form]) {
1296 Diag(TheCall->getArg(NumArgs[Form])->getLocStart(),
1297 diag::err_typecheck_call_too_many_args)
1298 << 0 << NumArgs[Form] << TheCall->getNumArgs()
1299 << TheCall->getCallee()->getSourceRange();
1303 // Inspect the first argument of the atomic operation.
1304 Expr *Ptr = TheCall->getArg(0);
1305 Ptr = DefaultFunctionArrayLvalueConversion(Ptr).get();
1306 const PointerType *pointerType = Ptr->getType()->getAs<PointerType>();
1308 Diag(DRE->getLocStart(), diag::err_atomic_builtin_must_be_pointer)
1309 << Ptr->getType() << Ptr->getSourceRange();
1313 // For a __c11 builtin, this should be a pointer to an _Atomic type.
1314 QualType AtomTy = pointerType->getPointeeType(); // 'A'
1315 QualType ValType = AtomTy; // 'C'
1317 if (!AtomTy->isAtomicType()) {
1318 Diag(DRE->getLocStart(), diag::err_atomic_op_needs_atomic)
1319 << Ptr->getType() << Ptr->getSourceRange();
1322 if (AtomTy.isConstQualified()) {
1323 Diag(DRE->getLocStart(), diag::err_atomic_op_needs_non_const_atomic)
1324 << Ptr->getType() << Ptr->getSourceRange();
1327 ValType = AtomTy->getAs<AtomicType>()->getValueType();
1330 // For an arithmetic operation, the implied arithmetic must be well-formed.
1331 if (Form == Arithmetic) {
1332 // gcc does not enforce these rules for GNU atomics, but we do so for sanity.
1333 if (IsAddSub && !ValType->isIntegerType() && !ValType->isPointerType()) {
1334 Diag(DRE->getLocStart(), diag::err_atomic_op_needs_atomic_int_or_ptr)
1335 << IsC11 << Ptr->getType() << Ptr->getSourceRange();
1338 if (!IsAddSub && !ValType->isIntegerType()) {
1339 Diag(DRE->getLocStart(), diag::err_atomic_op_bitwise_needs_atomic_int)
1340 << IsC11 << Ptr->getType() << Ptr->getSourceRange();
1343 } else if (IsN && !ValType->isIntegerType() && !ValType->isPointerType()) {
1344 // For __atomic_*_n operations, the value type must be a scalar integral or
1345 // pointer type which is 1, 2, 4, 8 or 16 bytes in length.
1346 Diag(DRE->getLocStart(), diag::err_atomic_op_needs_atomic_int_or_ptr)
1347 << IsC11 << Ptr->getType() << Ptr->getSourceRange();
1351 if (!IsC11 && !AtomTy.isTriviallyCopyableType(Context) &&
1352 !AtomTy->isScalarType()) {
1353 // For GNU atomics, require a trivially-copyable type. This is not part of
1354 // the GNU atomics specification, but we enforce it for sanity.
1355 Diag(DRE->getLocStart(), diag::err_atomic_op_needs_trivial_copy)
1356 << Ptr->getType() << Ptr->getSourceRange();
1360 // FIXME: For any builtin other than a load, the ValType must not be
1363 switch (ValType.getObjCLifetime()) {
1364 case Qualifiers::OCL_None:
1365 case Qualifiers::OCL_ExplicitNone:
1369 case Qualifiers::OCL_Weak:
1370 case Qualifiers::OCL_Strong:
1371 case Qualifiers::OCL_Autoreleasing:
1372 // FIXME: Can this happen? By this point, ValType should be known
1373 // to be trivially copyable.
1374 Diag(DRE->getLocStart(), diag::err_arc_atomic_ownership)
1375 << ValType << Ptr->getSourceRange();
1379 QualType ResultType = ValType;
1380 if (Form == Copy || Form == GNUXchg || Form == Init)
1381 ResultType = Context.VoidTy;
1382 else if (Form == C11CmpXchg || Form == GNUCmpXchg)
1383 ResultType = Context.BoolTy;
1385 // The type of a parameter passed 'by value'. In the GNU atomics, such
1386 // arguments are actually passed as pointers.
1387 QualType ByValType = ValType; // 'CP'
1389 ByValType = Ptr->getType();
1391 // The first argument --- the pointer --- has a fixed type; we
1392 // deduce the types of the rest of the arguments accordingly. Walk
1393 // the remaining arguments, converting them to the deduced value type.
1394 for (unsigned i = 1; i != NumArgs[Form]; ++i) {
1396 if (i < NumVals[Form] + 1) {
1399 // The second argument is the non-atomic operand. For arithmetic, this
1400 // is always passed by value, and for a compare_exchange it is always
1401 // passed by address. For the rest, GNU uses by-address and C11 uses
1403 assert(Form != Load);
1404 if (Form == Init || (Form == Arithmetic && ValType->isIntegerType()))
1406 else if (Form == Copy || Form == Xchg)
1408 else if (Form == Arithmetic)
1409 Ty = Context.getPointerDiffType();
1411 Ty = Context.getPointerType(ValType.getUnqualifiedType());
1414 // The third argument to compare_exchange / GNU exchange is a
1415 // (pointer to a) desired value.
1419 // The fourth argument to GNU compare_exchange is a 'weak' flag.
1420 Ty = Context.BoolTy;
1424 // The order(s) are always converted to int.
1428 InitializedEntity Entity =
1429 InitializedEntity::InitializeParameter(Context, Ty, false);
1430 ExprResult Arg = TheCall->getArg(i);
1431 Arg = PerformCopyInitialization(Entity, SourceLocation(), Arg);
1432 if (Arg.isInvalid())
1434 TheCall->setArg(i, Arg.get());
1437 // Permute the arguments into a 'consistent' order.
1438 SmallVector<Expr*, 5> SubExprs;
1439 SubExprs.push_back(Ptr);
1442 // Note, AtomicExpr::getVal1() has a special case for this atomic.
1443 SubExprs.push_back(TheCall->getArg(1)); // Val1
1446 SubExprs.push_back(TheCall->getArg(1)); // Order
1451 SubExprs.push_back(TheCall->getArg(2)); // Order
1452 SubExprs.push_back(TheCall->getArg(1)); // Val1
1455 // Note, AtomicExpr::getVal2() has a special case for this atomic.
1456 SubExprs.push_back(TheCall->getArg(3)); // Order
1457 SubExprs.push_back(TheCall->getArg(1)); // Val1
1458 SubExprs.push_back(TheCall->getArg(2)); // Val2
1461 SubExprs.push_back(TheCall->getArg(3)); // Order
1462 SubExprs.push_back(TheCall->getArg(1)); // Val1
1463 SubExprs.push_back(TheCall->getArg(4)); // OrderFail
1464 SubExprs.push_back(TheCall->getArg(2)); // Val2
1467 SubExprs.push_back(TheCall->getArg(4)); // Order
1468 SubExprs.push_back(TheCall->getArg(1)); // Val1
1469 SubExprs.push_back(TheCall->getArg(5)); // OrderFail
1470 SubExprs.push_back(TheCall->getArg(2)); // Val2
1471 SubExprs.push_back(TheCall->getArg(3)); // Weak
1475 if (SubExprs.size() >= 2 && Form != Init) {
1476 llvm::APSInt Result(32);
1477 if (SubExprs[1]->isIntegerConstantExpr(Result, Context) &&
1478 !isValidOrderingForOp(Result.getSExtValue(), Op))
1479 Diag(SubExprs[1]->getLocStart(),
1480 diag::warn_atomic_op_has_invalid_memory_order)
1481 << SubExprs[1]->getSourceRange();
1484 AtomicExpr *AE = new (Context) AtomicExpr(TheCall->getCallee()->getLocStart(),
1485 SubExprs, ResultType, Op,
1486 TheCall->getRParenLoc());
1488 if ((Op == AtomicExpr::AO__c11_atomic_load ||
1489 (Op == AtomicExpr::AO__c11_atomic_store)) &&
1490 Context.AtomicUsesUnsupportedLibcall(AE))
1491 Diag(AE->getLocStart(), diag::err_atomic_load_store_uses_lib) <<
1492 ((Op == AtomicExpr::AO__c11_atomic_load) ? 0 : 1);
1498 /// checkBuiltinArgument - Given a call to a builtin function, perform
1499 /// normal type-checking on the given argument, updating the call in
1500 /// place. This is useful when a builtin function requires custom
1501 /// type-checking for some of its arguments but not necessarily all of
1504 /// Returns true on error.
1505 static bool checkBuiltinArgument(Sema &S, CallExpr *E, unsigned ArgIndex) {
1506 FunctionDecl *Fn = E->getDirectCallee();
1507 assert(Fn && "builtin call without direct callee!");
1509 ParmVarDecl *Param = Fn->getParamDecl(ArgIndex);
1510 InitializedEntity Entity =
1511 InitializedEntity::InitializeParameter(S.Context, Param);
1513 ExprResult Arg = E->getArg(0);
1514 Arg = S.PerformCopyInitialization(Entity, SourceLocation(), Arg);
1515 if (Arg.isInvalid())
1518 E->setArg(ArgIndex, Arg.get());
1522 /// SemaBuiltinAtomicOverloaded - We have a call to a function like
1523 /// __sync_fetch_and_add, which is an overloaded function based on the pointer
1524 /// type of its first argument. The main ActOnCallExpr routines have already
1525 /// promoted the types of arguments because all of these calls are prototyped as
1528 /// This function goes through and does final semantic checking for these
1531 Sema::SemaBuiltinAtomicOverloaded(ExprResult TheCallResult) {
1532 CallExpr *TheCall = (CallExpr *)TheCallResult.get();
1533 DeclRefExpr *DRE =cast<DeclRefExpr>(TheCall->getCallee()->IgnoreParenCasts());
1534 FunctionDecl *FDecl = cast<FunctionDecl>(DRE->getDecl());
1536 // Ensure that we have at least one argument to do type inference from.
1537 if (TheCall->getNumArgs() < 1) {
1538 Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args_at_least)
1539 << 0 << 1 << TheCall->getNumArgs()
1540 << TheCall->getCallee()->getSourceRange();
1544 // Inspect the first argument of the atomic builtin. This should always be
1545 // a pointer type, whose element is an integral scalar or pointer type.
1546 // Because it is a pointer type, we don't have to worry about any implicit
1548 // FIXME: We don't allow floating point scalars as input.
1549 Expr *FirstArg = TheCall->getArg(0);
1550 ExprResult FirstArgResult = DefaultFunctionArrayLvalueConversion(FirstArg);
1551 if (FirstArgResult.isInvalid())
1553 FirstArg = FirstArgResult.get();
1554 TheCall->setArg(0, FirstArg);
1556 const PointerType *pointerType = FirstArg->getType()->getAs<PointerType>();
1558 Diag(DRE->getLocStart(), diag::err_atomic_builtin_must_be_pointer)
1559 << FirstArg->getType() << FirstArg->getSourceRange();
1563 QualType ValType = pointerType->getPointeeType();
1564 if (!ValType->isIntegerType() && !ValType->isAnyPointerType() &&
1565 !ValType->isBlockPointerType()) {
1566 Diag(DRE->getLocStart(), diag::err_atomic_builtin_must_be_pointer_intptr)
1567 << FirstArg->getType() << FirstArg->getSourceRange();
1571 switch (ValType.getObjCLifetime()) {
1572 case Qualifiers::OCL_None:
1573 case Qualifiers::OCL_ExplicitNone:
1577 case Qualifiers::OCL_Weak:
1578 case Qualifiers::OCL_Strong:
1579 case Qualifiers::OCL_Autoreleasing:
1580 Diag(DRE->getLocStart(), diag::err_arc_atomic_ownership)
1581 << ValType << FirstArg->getSourceRange();
1585 // Strip any qualifiers off ValType.
1586 ValType = ValType.getUnqualifiedType();
1588 // The majority of builtins return a value, but a few have special return
1589 // types, so allow them to override appropriately below.
1590 QualType ResultType = ValType;
1592 // We need to figure out which concrete builtin this maps onto. For example,
1593 // __sync_fetch_and_add with a 2 byte object turns into
1594 // __sync_fetch_and_add_2.
1595 #define BUILTIN_ROW(x) \
1596 { Builtin::BI##x##_1, Builtin::BI##x##_2, Builtin::BI##x##_4, \
1597 Builtin::BI##x##_8, Builtin::BI##x##_16 }
1599 static const unsigned BuiltinIndices[][5] = {
1600 BUILTIN_ROW(__sync_fetch_and_add),
1601 BUILTIN_ROW(__sync_fetch_and_sub),
1602 BUILTIN_ROW(__sync_fetch_and_or),
1603 BUILTIN_ROW(__sync_fetch_and_and),
1604 BUILTIN_ROW(__sync_fetch_and_xor),
1605 BUILTIN_ROW(__sync_fetch_and_nand),
1607 BUILTIN_ROW(__sync_add_and_fetch),
1608 BUILTIN_ROW(__sync_sub_and_fetch),
1609 BUILTIN_ROW(__sync_and_and_fetch),
1610 BUILTIN_ROW(__sync_or_and_fetch),
1611 BUILTIN_ROW(__sync_xor_and_fetch),
1612 BUILTIN_ROW(__sync_nand_and_fetch),
1614 BUILTIN_ROW(__sync_val_compare_and_swap),
1615 BUILTIN_ROW(__sync_bool_compare_and_swap),
1616 BUILTIN_ROW(__sync_lock_test_and_set),
1617 BUILTIN_ROW(__sync_lock_release),
1618 BUILTIN_ROW(__sync_swap)
1622 // Determine the index of the size.
1624 switch (Context.getTypeSizeInChars(ValType).getQuantity()) {
1625 case 1: SizeIndex = 0; break;
1626 case 2: SizeIndex = 1; break;
1627 case 4: SizeIndex = 2; break;
1628 case 8: SizeIndex = 3; break;
1629 case 16: SizeIndex = 4; break;
1631 Diag(DRE->getLocStart(), diag::err_atomic_builtin_pointer_size)
1632 << FirstArg->getType() << FirstArg->getSourceRange();
1636 // Each of these builtins has one pointer argument, followed by some number of
1637 // values (0, 1 or 2) followed by a potentially empty varags list of stuff
1638 // that we ignore. Find out which row of BuiltinIndices to read from as well
1639 // as the number of fixed args.
1640 unsigned BuiltinID = FDecl->getBuiltinID();
1641 unsigned BuiltinIndex, NumFixed = 1;
1642 bool WarnAboutSemanticsChange = false;
1643 switch (BuiltinID) {
1644 default: llvm_unreachable("Unknown overloaded atomic builtin!");
1645 case Builtin::BI__sync_fetch_and_add:
1646 case Builtin::BI__sync_fetch_and_add_1:
1647 case Builtin::BI__sync_fetch_and_add_2:
1648 case Builtin::BI__sync_fetch_and_add_4:
1649 case Builtin::BI__sync_fetch_and_add_8:
1650 case Builtin::BI__sync_fetch_and_add_16:
1654 case Builtin::BI__sync_fetch_and_sub:
1655 case Builtin::BI__sync_fetch_and_sub_1:
1656 case Builtin::BI__sync_fetch_and_sub_2:
1657 case Builtin::BI__sync_fetch_and_sub_4:
1658 case Builtin::BI__sync_fetch_and_sub_8:
1659 case Builtin::BI__sync_fetch_and_sub_16:
1663 case Builtin::BI__sync_fetch_and_or:
1664 case Builtin::BI__sync_fetch_and_or_1:
1665 case Builtin::BI__sync_fetch_and_or_2:
1666 case Builtin::BI__sync_fetch_and_or_4:
1667 case Builtin::BI__sync_fetch_and_or_8:
1668 case Builtin::BI__sync_fetch_and_or_16:
1672 case Builtin::BI__sync_fetch_and_and:
1673 case Builtin::BI__sync_fetch_and_and_1:
1674 case Builtin::BI__sync_fetch_and_and_2:
1675 case Builtin::BI__sync_fetch_and_and_4:
1676 case Builtin::BI__sync_fetch_and_and_8:
1677 case Builtin::BI__sync_fetch_and_and_16:
1681 case Builtin::BI__sync_fetch_and_xor:
1682 case Builtin::BI__sync_fetch_and_xor_1:
1683 case Builtin::BI__sync_fetch_and_xor_2:
1684 case Builtin::BI__sync_fetch_and_xor_4:
1685 case Builtin::BI__sync_fetch_and_xor_8:
1686 case Builtin::BI__sync_fetch_and_xor_16:
1690 case Builtin::BI__sync_fetch_and_nand:
1691 case Builtin::BI__sync_fetch_and_nand_1:
1692 case Builtin::BI__sync_fetch_and_nand_2:
1693 case Builtin::BI__sync_fetch_and_nand_4:
1694 case Builtin::BI__sync_fetch_and_nand_8:
1695 case Builtin::BI__sync_fetch_and_nand_16:
1697 WarnAboutSemanticsChange = true;
1700 case Builtin::BI__sync_add_and_fetch:
1701 case Builtin::BI__sync_add_and_fetch_1:
1702 case Builtin::BI__sync_add_and_fetch_2:
1703 case Builtin::BI__sync_add_and_fetch_4:
1704 case Builtin::BI__sync_add_and_fetch_8:
1705 case Builtin::BI__sync_add_and_fetch_16:
1709 case Builtin::BI__sync_sub_and_fetch:
1710 case Builtin::BI__sync_sub_and_fetch_1:
1711 case Builtin::BI__sync_sub_and_fetch_2:
1712 case Builtin::BI__sync_sub_and_fetch_4:
1713 case Builtin::BI__sync_sub_and_fetch_8:
1714 case Builtin::BI__sync_sub_and_fetch_16:
1718 case Builtin::BI__sync_and_and_fetch:
1719 case Builtin::BI__sync_and_and_fetch_1:
1720 case Builtin::BI__sync_and_and_fetch_2:
1721 case Builtin::BI__sync_and_and_fetch_4:
1722 case Builtin::BI__sync_and_and_fetch_8:
1723 case Builtin::BI__sync_and_and_fetch_16:
1727 case Builtin::BI__sync_or_and_fetch:
1728 case Builtin::BI__sync_or_and_fetch_1:
1729 case Builtin::BI__sync_or_and_fetch_2:
1730 case Builtin::BI__sync_or_and_fetch_4:
1731 case Builtin::BI__sync_or_and_fetch_8:
1732 case Builtin::BI__sync_or_and_fetch_16:
1736 case Builtin::BI__sync_xor_and_fetch:
1737 case Builtin::BI__sync_xor_and_fetch_1:
1738 case Builtin::BI__sync_xor_and_fetch_2:
1739 case Builtin::BI__sync_xor_and_fetch_4:
1740 case Builtin::BI__sync_xor_and_fetch_8:
1741 case Builtin::BI__sync_xor_and_fetch_16:
1745 case Builtin::BI__sync_nand_and_fetch:
1746 case Builtin::BI__sync_nand_and_fetch_1:
1747 case Builtin::BI__sync_nand_and_fetch_2:
1748 case Builtin::BI__sync_nand_and_fetch_4:
1749 case Builtin::BI__sync_nand_and_fetch_8:
1750 case Builtin::BI__sync_nand_and_fetch_16:
1752 WarnAboutSemanticsChange = true;
1755 case Builtin::BI__sync_val_compare_and_swap:
1756 case Builtin::BI__sync_val_compare_and_swap_1:
1757 case Builtin::BI__sync_val_compare_and_swap_2:
1758 case Builtin::BI__sync_val_compare_and_swap_4:
1759 case Builtin::BI__sync_val_compare_and_swap_8:
1760 case Builtin::BI__sync_val_compare_and_swap_16:
1765 case Builtin::BI__sync_bool_compare_and_swap:
1766 case Builtin::BI__sync_bool_compare_and_swap_1:
1767 case Builtin::BI__sync_bool_compare_and_swap_2:
1768 case Builtin::BI__sync_bool_compare_and_swap_4:
1769 case Builtin::BI__sync_bool_compare_and_swap_8:
1770 case Builtin::BI__sync_bool_compare_and_swap_16:
1773 ResultType = Context.BoolTy;
1776 case Builtin::BI__sync_lock_test_and_set:
1777 case Builtin::BI__sync_lock_test_and_set_1:
1778 case Builtin::BI__sync_lock_test_and_set_2:
1779 case Builtin::BI__sync_lock_test_and_set_4:
1780 case Builtin::BI__sync_lock_test_and_set_8:
1781 case Builtin::BI__sync_lock_test_and_set_16:
1785 case Builtin::BI__sync_lock_release:
1786 case Builtin::BI__sync_lock_release_1:
1787 case Builtin::BI__sync_lock_release_2:
1788 case Builtin::BI__sync_lock_release_4:
1789 case Builtin::BI__sync_lock_release_8:
1790 case Builtin::BI__sync_lock_release_16:
1793 ResultType = Context.VoidTy;
1796 case Builtin::BI__sync_swap:
1797 case Builtin::BI__sync_swap_1:
1798 case Builtin::BI__sync_swap_2:
1799 case Builtin::BI__sync_swap_4:
1800 case Builtin::BI__sync_swap_8:
1801 case Builtin::BI__sync_swap_16:
1806 // Now that we know how many fixed arguments we expect, first check that we
1807 // have at least that many.
1808 if (TheCall->getNumArgs() < 1+NumFixed) {
1809 Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args_at_least)
1810 << 0 << 1+NumFixed << TheCall->getNumArgs()
1811 << TheCall->getCallee()->getSourceRange();
1815 if (WarnAboutSemanticsChange) {
1816 Diag(TheCall->getLocEnd(), diag::warn_sync_fetch_and_nand_semantics_change)
1817 << TheCall->getCallee()->getSourceRange();
1820 // Get the decl for the concrete builtin from this, we can tell what the
1821 // concrete integer type we should convert to is.
1822 unsigned NewBuiltinID = BuiltinIndices[BuiltinIndex][SizeIndex];
1823 const char *NewBuiltinName = Context.BuiltinInfo.GetName(NewBuiltinID);
1824 FunctionDecl *NewBuiltinDecl;
1825 if (NewBuiltinID == BuiltinID)
1826 NewBuiltinDecl = FDecl;
1828 // Perform builtin lookup to avoid redeclaring it.
1829 DeclarationName DN(&Context.Idents.get(NewBuiltinName));
1830 LookupResult Res(*this, DN, DRE->getLocStart(), LookupOrdinaryName);
1831 LookupName(Res, TUScope, /*AllowBuiltinCreation=*/true);
1832 assert(Res.getFoundDecl());
1833 NewBuiltinDecl = dyn_cast<FunctionDecl>(Res.getFoundDecl());
1834 if (!NewBuiltinDecl)
1838 // The first argument --- the pointer --- has a fixed type; we
1839 // deduce the types of the rest of the arguments accordingly. Walk
1840 // the remaining arguments, converting them to the deduced value type.
1841 for (unsigned i = 0; i != NumFixed; ++i) {
1842 ExprResult Arg = TheCall->getArg(i+1);
1844 // GCC does an implicit conversion to the pointer or integer ValType. This
1845 // can fail in some cases (1i -> int**), check for this error case now.
1846 // Initialize the argument.
1847 InitializedEntity Entity = InitializedEntity::InitializeParameter(Context,
1848 ValType, /*consume*/ false);
1849 Arg = PerformCopyInitialization(Entity, SourceLocation(), Arg);
1850 if (Arg.isInvalid())
1853 // Okay, we have something that *can* be converted to the right type. Check
1854 // to see if there is a potentially weird extension going on here. This can
1855 // happen when you do an atomic operation on something like an char* and
1856 // pass in 42. The 42 gets converted to char. This is even more strange
1857 // for things like 45.123 -> char, etc.
1858 // FIXME: Do this check.
1859 TheCall->setArg(i+1, Arg.get());
1862 ASTContext& Context = this->getASTContext();
1864 // Create a new DeclRefExpr to refer to the new decl.
1865 DeclRefExpr* NewDRE = DeclRefExpr::Create(
1867 DRE->getQualifierLoc(),
1870 /*enclosing*/ false,
1872 Context.BuiltinFnTy,
1873 DRE->getValueKind());
1875 // Set the callee in the CallExpr.
1876 // FIXME: This loses syntactic information.
1877 QualType CalleePtrTy = Context.getPointerType(NewBuiltinDecl->getType());
1878 ExprResult PromotedCall = ImpCastExprToType(NewDRE, CalleePtrTy,
1879 CK_BuiltinFnToFnPtr);
1880 TheCall->setCallee(PromotedCall.get());
1882 // Change the result type of the call to match the original value type. This
1883 // is arbitrary, but the codegen for these builtins ins design to handle it
1885 TheCall->setType(ResultType);
1887 return TheCallResult;
1890 /// CheckObjCString - Checks that the argument to the builtin
1891 /// CFString constructor is correct
1892 /// Note: It might also make sense to do the UTF-16 conversion here (would
1893 /// simplify the backend).
1894 bool Sema::CheckObjCString(Expr *Arg) {
1895 Arg = Arg->IgnoreParenCasts();
1896 StringLiteral *Literal = dyn_cast<StringLiteral>(Arg);
1898 if (!Literal || !Literal->isAscii()) {
1899 Diag(Arg->getLocStart(), diag::err_cfstring_literal_not_string_constant)
1900 << Arg->getSourceRange();
1904 if (Literal->containsNonAsciiOrNull()) {
1905 StringRef String = Literal->getString();
1906 unsigned NumBytes = String.size();
1907 SmallVector<UTF16, 128> ToBuf(NumBytes);
1908 const UTF8 *FromPtr = (const UTF8 *)String.data();
1909 UTF16 *ToPtr = &ToBuf[0];
1911 ConversionResult Result = ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes,
1912 &ToPtr, ToPtr + NumBytes,
1914 // Check for conversion failure.
1915 if (Result != conversionOK)
1916 Diag(Arg->getLocStart(),
1917 diag::warn_cfstring_truncated) << Arg->getSourceRange();
1922 /// SemaBuiltinVAStart - Check the arguments to __builtin_va_start for validity.
1923 /// Emit an error and return true on failure, return false on success.
1924 bool Sema::SemaBuiltinVAStart(CallExpr *TheCall) {
1925 Expr *Fn = TheCall->getCallee();
1926 if (TheCall->getNumArgs() > 2) {
1927 Diag(TheCall->getArg(2)->getLocStart(),
1928 diag::err_typecheck_call_too_many_args)
1929 << 0 /*function call*/ << 2 << TheCall->getNumArgs()
1930 << Fn->getSourceRange()
1931 << SourceRange(TheCall->getArg(2)->getLocStart(),
1932 (*(TheCall->arg_end()-1))->getLocEnd());
1936 if (TheCall->getNumArgs() < 2) {
1937 return Diag(TheCall->getLocEnd(),
1938 diag::err_typecheck_call_too_few_args_at_least)
1939 << 0 /*function call*/ << 2 << TheCall->getNumArgs();
1942 // Type-check the first argument normally.
1943 if (checkBuiltinArgument(*this, TheCall, 0))
1946 // Determine whether the current function is variadic or not.
1947 BlockScopeInfo *CurBlock = getCurBlock();
1950 isVariadic = CurBlock->TheDecl->isVariadic();
1951 else if (FunctionDecl *FD = getCurFunctionDecl())
1952 isVariadic = FD->isVariadic();
1954 isVariadic = getCurMethodDecl()->isVariadic();
1957 Diag(Fn->getLocStart(), diag::err_va_start_used_in_non_variadic_function);
1961 // Verify that the second argument to the builtin is the last argument of the
1962 // current function or method.
1963 bool SecondArgIsLastNamedArgument = false;
1964 const Expr *Arg = TheCall->getArg(1)->IgnoreParenCasts();
1966 // These are valid if SecondArgIsLastNamedArgument is false after the next
1969 SourceLocation ParamLoc;
1971 if (const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(Arg)) {
1972 if (const ParmVarDecl *PV = dyn_cast<ParmVarDecl>(DR->getDecl())) {
1973 // FIXME: This isn't correct for methods (results in bogus warning).
1974 // Get the last formal in the current function.
1975 const ParmVarDecl *LastArg;
1977 LastArg = *(CurBlock->TheDecl->param_end()-1);
1978 else if (FunctionDecl *FD = getCurFunctionDecl())
1979 LastArg = *(FD->param_end()-1);
1981 LastArg = *(getCurMethodDecl()->param_end()-1);
1982 SecondArgIsLastNamedArgument = PV == LastArg;
1984 Type = PV->getType();
1985 ParamLoc = PV->getLocation();
1989 if (!SecondArgIsLastNamedArgument)
1990 Diag(TheCall->getArg(1)->getLocStart(),
1991 diag::warn_second_parameter_of_va_start_not_last_named_argument);
1992 else if (Type->isReferenceType()) {
1993 Diag(Arg->getLocStart(),
1994 diag::warn_va_start_of_reference_type_is_undefined);
1995 Diag(ParamLoc, diag::note_parameter_type) << Type;
1998 TheCall->setType(Context.VoidTy);
2002 bool Sema::SemaBuiltinVAStartARM(CallExpr *Call) {
2003 // void __va_start(va_list *ap, const char *named_addr, size_t slot_size,
2004 // const char *named_addr);
2006 Expr *Func = Call->getCallee();
2008 if (Call->getNumArgs() < 3)
2009 return Diag(Call->getLocEnd(),
2010 diag::err_typecheck_call_too_few_args_at_least)
2011 << 0 /*function call*/ << 3 << Call->getNumArgs();
2013 // Determine whether the current function is variadic or not.
2015 if (BlockScopeInfo *CurBlock = getCurBlock())
2016 IsVariadic = CurBlock->TheDecl->isVariadic();
2017 else if (FunctionDecl *FD = getCurFunctionDecl())
2018 IsVariadic = FD->isVariadic();
2019 else if (ObjCMethodDecl *MD = getCurMethodDecl())
2020 IsVariadic = MD->isVariadic();
2022 llvm_unreachable("unexpected statement type");
2025 Diag(Func->getLocStart(), diag::err_va_start_used_in_non_variadic_function);
2029 // Type-check the first argument normally.
2030 if (checkBuiltinArgument(*this, Call, 0))
2033 static const struct {
2036 } ArgumentTypes[] = {
2037 { 1, Context.getPointerType(Context.CharTy.withConst()) },
2038 { 2, Context.getSizeType() },
2041 for (const auto &AT : ArgumentTypes) {
2042 const Expr *Arg = Call->getArg(AT.ArgNo)->IgnoreParens();
2043 if (Arg->getType().getCanonicalType() == AT.Type.getCanonicalType())
2045 Diag(Arg->getLocStart(), diag::err_typecheck_convert_incompatible)
2046 << Arg->getType() << AT.Type << 1 /* different class */
2047 << 0 /* qualifier difference */ << 3 /* parameter mismatch */
2048 << AT.ArgNo + 1 << Arg->getType() << AT.Type;
2054 /// SemaBuiltinUnorderedCompare - Handle functions like __builtin_isgreater and
2055 /// friends. This is declared to take (...), so we have to check everything.
2056 bool Sema::SemaBuiltinUnorderedCompare(CallExpr *TheCall) {
2057 if (TheCall->getNumArgs() < 2)
2058 return Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args)
2059 << 0 << 2 << TheCall->getNumArgs()/*function call*/;
2060 if (TheCall->getNumArgs() > 2)
2061 return Diag(TheCall->getArg(2)->getLocStart(),
2062 diag::err_typecheck_call_too_many_args)
2063 << 0 /*function call*/ << 2 << TheCall->getNumArgs()
2064 << SourceRange(TheCall->getArg(2)->getLocStart(),
2065 (*(TheCall->arg_end()-1))->getLocEnd());
2067 ExprResult OrigArg0 = TheCall->getArg(0);
2068 ExprResult OrigArg1 = TheCall->getArg(1);
2070 // Do standard promotions between the two arguments, returning their common
2072 QualType Res = UsualArithmeticConversions(OrigArg0, OrigArg1, false);
2073 if (OrigArg0.isInvalid() || OrigArg1.isInvalid())
2076 // Make sure any conversions are pushed back into the call; this is
2077 // type safe since unordered compare builtins are declared as "_Bool
2079 TheCall->setArg(0, OrigArg0.get());
2080 TheCall->setArg(1, OrigArg1.get());
2082 if (OrigArg0.get()->isTypeDependent() || OrigArg1.get()->isTypeDependent())
2085 // If the common type isn't a real floating type, then the arguments were
2086 // invalid for this operation.
2087 if (Res.isNull() || !Res->isRealFloatingType())
2088 return Diag(OrigArg0.get()->getLocStart(),
2089 diag::err_typecheck_call_invalid_ordered_compare)
2090 << OrigArg0.get()->getType() << OrigArg1.get()->getType()
2091 << SourceRange(OrigArg0.get()->getLocStart(), OrigArg1.get()->getLocEnd());
2096 /// SemaBuiltinSemaBuiltinFPClassification - Handle functions like
2097 /// __builtin_isnan and friends. This is declared to take (...), so we have
2098 /// to check everything. We expect the last argument to be a floating point
2100 bool Sema::SemaBuiltinFPClassification(CallExpr *TheCall, unsigned NumArgs) {
2101 if (TheCall->getNumArgs() < NumArgs)
2102 return Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args)
2103 << 0 << NumArgs << TheCall->getNumArgs()/*function call*/;
2104 if (TheCall->getNumArgs() > NumArgs)
2105 return Diag(TheCall->getArg(NumArgs)->getLocStart(),
2106 diag::err_typecheck_call_too_many_args)
2107 << 0 /*function call*/ << NumArgs << TheCall->getNumArgs()
2108 << SourceRange(TheCall->getArg(NumArgs)->getLocStart(),
2109 (*(TheCall->arg_end()-1))->getLocEnd());
2111 Expr *OrigArg = TheCall->getArg(NumArgs-1);
2113 if (OrigArg->isTypeDependent())
2116 // This operation requires a non-_Complex floating-point number.
2117 if (!OrigArg->getType()->isRealFloatingType())
2118 return Diag(OrigArg->getLocStart(),
2119 diag::err_typecheck_call_invalid_unary_fp)
2120 << OrigArg->getType() << OrigArg->getSourceRange();
2122 // If this is an implicit conversion from float -> double, remove it.
2123 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(OrigArg)) {
2124 Expr *CastArg = Cast->getSubExpr();
2125 if (CastArg->getType()->isSpecificBuiltinType(BuiltinType::Float)) {
2126 assert(Cast->getType()->isSpecificBuiltinType(BuiltinType::Double) &&
2127 "promotion from float to double is the only expected cast here");
2128 Cast->setSubExpr(nullptr);
2129 TheCall->setArg(NumArgs-1, CastArg);
2136 /// SemaBuiltinShuffleVector - Handle __builtin_shufflevector.
2137 // This is declared to take (...), so we have to check everything.
2138 ExprResult Sema::SemaBuiltinShuffleVector(CallExpr *TheCall) {
2139 if (TheCall->getNumArgs() < 2)
2140 return ExprError(Diag(TheCall->getLocEnd(),
2141 diag::err_typecheck_call_too_few_args_at_least)
2142 << 0 /*function call*/ << 2 << TheCall->getNumArgs()
2143 << TheCall->getSourceRange());
2145 // Determine which of the following types of shufflevector we're checking:
2146 // 1) unary, vector mask: (lhs, mask)
2147 // 2) binary, vector mask: (lhs, rhs, mask)
2148 // 3) binary, scalar mask: (lhs, rhs, index, ..., index)
2149 QualType resType = TheCall->getArg(0)->getType();
2150 unsigned numElements = 0;
2152 if (!TheCall->getArg(0)->isTypeDependent() &&
2153 !TheCall->getArg(1)->isTypeDependent()) {
2154 QualType LHSType = TheCall->getArg(0)->getType();
2155 QualType RHSType = TheCall->getArg(1)->getType();
2157 if (!LHSType->isVectorType() || !RHSType->isVectorType())
2158 return ExprError(Diag(TheCall->getLocStart(),
2159 diag::err_shufflevector_non_vector)
2160 << SourceRange(TheCall->getArg(0)->getLocStart(),
2161 TheCall->getArg(1)->getLocEnd()));
2163 numElements = LHSType->getAs<VectorType>()->getNumElements();
2164 unsigned numResElements = TheCall->getNumArgs() - 2;
2166 // Check to see if we have a call with 2 vector arguments, the unary shuffle
2167 // with mask. If so, verify that RHS is an integer vector type with the
2168 // same number of elts as lhs.
2169 if (TheCall->getNumArgs() == 2) {
2170 if (!RHSType->hasIntegerRepresentation() ||
2171 RHSType->getAs<VectorType>()->getNumElements() != numElements)
2172 return ExprError(Diag(TheCall->getLocStart(),
2173 diag::err_shufflevector_incompatible_vector)
2174 << SourceRange(TheCall->getArg(1)->getLocStart(),
2175 TheCall->getArg(1)->getLocEnd()));
2176 } else if (!Context.hasSameUnqualifiedType(LHSType, RHSType)) {
2177 return ExprError(Diag(TheCall->getLocStart(),
2178 diag::err_shufflevector_incompatible_vector)
2179 << SourceRange(TheCall->getArg(0)->getLocStart(),
2180 TheCall->getArg(1)->getLocEnd()));
2181 } else if (numElements != numResElements) {
2182 QualType eltType = LHSType->getAs<VectorType>()->getElementType();
2183 resType = Context.getVectorType(eltType, numResElements,
2184 VectorType::GenericVector);
2188 for (unsigned i = 2; i < TheCall->getNumArgs(); i++) {
2189 if (TheCall->getArg(i)->isTypeDependent() ||
2190 TheCall->getArg(i)->isValueDependent())
2193 llvm::APSInt Result(32);
2194 if (!TheCall->getArg(i)->isIntegerConstantExpr(Result, Context))
2195 return ExprError(Diag(TheCall->getLocStart(),
2196 diag::err_shufflevector_nonconstant_argument)
2197 << TheCall->getArg(i)->getSourceRange());
2199 // Allow -1 which will be translated to undef in the IR.
2200 if (Result.isSigned() && Result.isAllOnesValue())
2203 if (Result.getActiveBits() > 64 || Result.getZExtValue() >= numElements*2)
2204 return ExprError(Diag(TheCall->getLocStart(),
2205 diag::err_shufflevector_argument_too_large)
2206 << TheCall->getArg(i)->getSourceRange());
2209 SmallVector<Expr*, 32> exprs;
2211 for (unsigned i = 0, e = TheCall->getNumArgs(); i != e; i++) {
2212 exprs.push_back(TheCall->getArg(i));
2213 TheCall->setArg(i, nullptr);
2216 return new (Context) ShuffleVectorExpr(Context, exprs, resType,
2217 TheCall->getCallee()->getLocStart(),
2218 TheCall->getRParenLoc());
2221 /// SemaConvertVectorExpr - Handle __builtin_convertvector
2222 ExprResult Sema::SemaConvertVectorExpr(Expr *E, TypeSourceInfo *TInfo,
2223 SourceLocation BuiltinLoc,
2224 SourceLocation RParenLoc) {
2225 ExprValueKind VK = VK_RValue;
2226 ExprObjectKind OK = OK_Ordinary;
2227 QualType DstTy = TInfo->getType();
2228 QualType SrcTy = E->getType();
2230 if (!SrcTy->isVectorType() && !SrcTy->isDependentType())
2231 return ExprError(Diag(BuiltinLoc,
2232 diag::err_convertvector_non_vector)
2233 << E->getSourceRange());
2234 if (!DstTy->isVectorType() && !DstTy->isDependentType())
2235 return ExprError(Diag(BuiltinLoc,
2236 diag::err_convertvector_non_vector_type));
2238 if (!SrcTy->isDependentType() && !DstTy->isDependentType()) {
2239 unsigned SrcElts = SrcTy->getAs<VectorType>()->getNumElements();
2240 unsigned DstElts = DstTy->getAs<VectorType>()->getNumElements();
2241 if (SrcElts != DstElts)
2242 return ExprError(Diag(BuiltinLoc,
2243 diag::err_convertvector_incompatible_vector)
2244 << E->getSourceRange());
2247 return new (Context)
2248 ConvertVectorExpr(E, TInfo, DstTy, VK, OK, BuiltinLoc, RParenLoc);
2251 /// SemaBuiltinPrefetch - Handle __builtin_prefetch.
2252 // This is declared to take (const void*, ...) and can take two
2253 // optional constant int args.
2254 bool Sema::SemaBuiltinPrefetch(CallExpr *TheCall) {
2255 unsigned NumArgs = TheCall->getNumArgs();
2258 return Diag(TheCall->getLocEnd(),
2259 diag::err_typecheck_call_too_many_args_at_most)
2260 << 0 /*function call*/ << 3 << NumArgs
2261 << TheCall->getSourceRange();
2263 // Argument 0 is checked for us and the remaining arguments must be
2264 // constant integers.
2265 for (unsigned i = 1; i != NumArgs; ++i)
2266 if (SemaBuiltinConstantArgRange(TheCall, i, 0, i == 1 ? 1 : 3))
2272 /// SemaBuiltinAssume - Handle __assume (MS Extension).
2273 // __assume does not evaluate its arguments, and should warn if its argument
2274 // has side effects.
2275 bool Sema::SemaBuiltinAssume(CallExpr *TheCall) {
2276 Expr *Arg = TheCall->getArg(0);
2277 if (Arg->isInstantiationDependent()) return false;
2279 if (Arg->HasSideEffects(Context))
2280 return Diag(Arg->getLocStart(), diag::warn_assume_side_effects)
2281 << Arg->getSourceRange()
2282 << cast<FunctionDecl>(TheCall->getCalleeDecl())->getIdentifier();
2287 /// Handle __builtin_assume_aligned. This is declared
2288 /// as (const void*, size_t, ...) and can take one optional constant int arg.
2289 bool Sema::SemaBuiltinAssumeAligned(CallExpr *TheCall) {
2290 unsigned NumArgs = TheCall->getNumArgs();
2293 return Diag(TheCall->getLocEnd(),
2294 diag::err_typecheck_call_too_many_args_at_most)
2295 << 0 /*function call*/ << 3 << NumArgs
2296 << TheCall->getSourceRange();
2298 // The alignment must be a constant integer.
2299 Expr *Arg = TheCall->getArg(1);
2301 // We can't check the value of a dependent argument.
2302 if (!Arg->isTypeDependent() && !Arg->isValueDependent()) {
2303 llvm::APSInt Result;
2304 if (SemaBuiltinConstantArg(TheCall, 1, Result))
2307 if (!Result.isPowerOf2())
2308 return Diag(TheCall->getLocStart(),
2309 diag::err_alignment_not_power_of_two)
2310 << Arg->getSourceRange();
2314 ExprResult Arg(TheCall->getArg(2));
2315 InitializedEntity Entity = InitializedEntity::InitializeParameter(Context,
2316 Context.getSizeType(), false);
2317 Arg = PerformCopyInitialization(Entity, SourceLocation(), Arg);
2318 if (Arg.isInvalid()) return true;
2319 TheCall->setArg(2, Arg.get());
2325 /// SemaBuiltinConstantArg - Handle a check if argument ArgNum of CallExpr
2326 /// TheCall is a constant expression.
2327 bool Sema::SemaBuiltinConstantArg(CallExpr *TheCall, int ArgNum,
2328 llvm::APSInt &Result) {
2329 Expr *Arg = TheCall->getArg(ArgNum);
2330 DeclRefExpr *DRE =cast<DeclRefExpr>(TheCall->getCallee()->IgnoreParenCasts());
2331 FunctionDecl *FDecl = cast<FunctionDecl>(DRE->getDecl());
2333 if (Arg->isTypeDependent() || Arg->isValueDependent()) return false;
2335 if (!Arg->isIntegerConstantExpr(Result, Context))
2336 return Diag(TheCall->getLocStart(), diag::err_constant_integer_arg_type)
2337 << FDecl->getDeclName() << Arg->getSourceRange();
2342 /// SemaBuiltinConstantArgRange - Handle a check if argument ArgNum of CallExpr
2343 /// TheCall is a constant expression in the range [Low, High].
2344 bool Sema::SemaBuiltinConstantArgRange(CallExpr *TheCall, int ArgNum,
2345 int Low, int High) {
2346 llvm::APSInt Result;
2348 // We can't check the value of a dependent argument.
2349 Expr *Arg = TheCall->getArg(ArgNum);
2350 if (Arg->isTypeDependent() || Arg->isValueDependent())
2353 // Check constant-ness first.
2354 if (SemaBuiltinConstantArg(TheCall, ArgNum, Result))
2357 if (Result.getSExtValue() < Low || Result.getSExtValue() > High)
2358 return Diag(TheCall->getLocStart(), diag::err_argument_invalid_range)
2359 << Low << High << Arg->getSourceRange();
2364 /// SemaBuiltinLongjmp - Handle __builtin_longjmp(void *env[5], int val).
2365 /// This checks that val is a constant 1.
2366 bool Sema::SemaBuiltinLongjmp(CallExpr *TheCall) {
2367 Expr *Arg = TheCall->getArg(1);
2368 llvm::APSInt Result;
2370 // TODO: This is less than ideal. Overload this to take a value.
2371 if (SemaBuiltinConstantArg(TheCall, 1, Result))
2375 return Diag(TheCall->getLocStart(), diag::err_builtin_longjmp_invalid_val)
2376 << SourceRange(Arg->getLocStart(), Arg->getLocEnd());
2382 enum StringLiteralCheckType {
2384 SLCT_UncheckedLiteral,
2389 // Determine if an expression is a string literal or constant string.
2390 // If this function returns false on the arguments to a function expecting a
2391 // format string, we will usually need to emit a warning.
2392 // True string literals are then checked by CheckFormatString.
2393 static StringLiteralCheckType
2394 checkFormatStringExpr(Sema &S, const Expr *E, ArrayRef<const Expr *> Args,
2395 bool HasVAListArg, unsigned format_idx,
2396 unsigned firstDataArg, Sema::FormatStringType Type,
2397 Sema::VariadicCallType CallType, bool InFunctionCall,
2398 llvm::SmallBitVector &CheckedVarArgs) {
2400 if (E->isTypeDependent() || E->isValueDependent())
2401 return SLCT_NotALiteral;
2403 E = E->IgnoreParenCasts();
2405 if (E->isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull))
2406 // Technically -Wformat-nonliteral does not warn about this case.
2407 // The behavior of printf and friends in this case is implementation
2408 // dependent. Ideally if the format string cannot be null then
2409 // it should have a 'nonnull' attribute in the function prototype.
2410 return SLCT_UncheckedLiteral;
2412 switch (E->getStmtClass()) {
2413 case Stmt::BinaryConditionalOperatorClass:
2414 case Stmt::ConditionalOperatorClass: {
2415 // The expression is a literal if both sub-expressions were, and it was
2416 // completely checked only if both sub-expressions were checked.
2417 const AbstractConditionalOperator *C =
2418 cast<AbstractConditionalOperator>(E);
2419 StringLiteralCheckType Left =
2420 checkFormatStringExpr(S, C->getTrueExpr(), Args,
2421 HasVAListArg, format_idx, firstDataArg,
2422 Type, CallType, InFunctionCall, CheckedVarArgs);
2423 if (Left == SLCT_NotALiteral)
2424 return SLCT_NotALiteral;
2425 StringLiteralCheckType Right =
2426 checkFormatStringExpr(S, C->getFalseExpr(), Args,
2427 HasVAListArg, format_idx, firstDataArg,
2428 Type, CallType, InFunctionCall, CheckedVarArgs);
2429 return Left < Right ? Left : Right;
2432 case Stmt::ImplicitCastExprClass: {
2433 E = cast<ImplicitCastExpr>(E)->getSubExpr();
2437 case Stmt::OpaqueValueExprClass:
2438 if (const Expr *src = cast<OpaqueValueExpr>(E)->getSourceExpr()) {
2442 return SLCT_NotALiteral;
2444 case Stmt::PredefinedExprClass:
2445 // While __func__, etc., are technically not string literals, they
2446 // cannot contain format specifiers and thus are not a security
2448 return SLCT_UncheckedLiteral;
2450 case Stmt::DeclRefExprClass: {
2451 const DeclRefExpr *DR = cast<DeclRefExpr>(E);
2453 // As an exception, do not flag errors for variables binding to
2454 // const string literals.
2455 if (const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl())) {
2456 bool isConstant = false;
2457 QualType T = DR->getType();
2459 if (const ArrayType *AT = S.Context.getAsArrayType(T)) {
2460 isConstant = AT->getElementType().isConstant(S.Context);
2461 } else if (const PointerType *PT = T->getAs<PointerType>()) {
2462 isConstant = T.isConstant(S.Context) &&
2463 PT->getPointeeType().isConstant(S.Context);
2464 } else if (T->isObjCObjectPointerType()) {
2465 // In ObjC, there is usually no "const ObjectPointer" type,
2466 // so don't check if the pointee type is constant.
2467 isConstant = T.isConstant(S.Context);
2471 if (const Expr *Init = VD->getAnyInitializer()) {
2472 // Look through initializers like const char c[] = { "foo" }
2473 if (const InitListExpr *InitList = dyn_cast<InitListExpr>(Init)) {
2474 if (InitList->isStringLiteralInit())
2475 Init = InitList->getInit(0)->IgnoreParenImpCasts();
2477 return checkFormatStringExpr(S, Init, Args,
2478 HasVAListArg, format_idx,
2479 firstDataArg, Type, CallType,
2480 /*InFunctionCall*/false, CheckedVarArgs);
2484 // For vprintf* functions (i.e., HasVAListArg==true), we add a
2485 // special check to see if the format string is a function parameter
2486 // of the function calling the printf function. If the function
2487 // has an attribute indicating it is a printf-like function, then we
2488 // should suppress warnings concerning non-literals being used in a call
2489 // to a vprintf function. For example:
2492 // logmessage(char const *fmt __attribute__ (format (printf, 1, 2)), ...){
2494 // va_start(ap, fmt);
2495 // vprintf(fmt, ap); // Do NOT emit a warning about "fmt".
2499 if (const ParmVarDecl *PV = dyn_cast<ParmVarDecl>(VD)) {
2500 if (const NamedDecl *ND = dyn_cast<NamedDecl>(PV->getDeclContext())) {
2501 int PVIndex = PV->getFunctionScopeIndex() + 1;
2502 for (const auto *PVFormat : ND->specific_attrs<FormatAttr>()) {
2503 // adjust for implicit parameter
2504 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(ND))
2505 if (MD->isInstance())
2507 // We also check if the formats are compatible.
2508 // We can't pass a 'scanf' string to a 'printf' function.
2509 if (PVIndex == PVFormat->getFormatIdx() &&
2510 Type == S.GetFormatStringType(PVFormat))
2511 return SLCT_UncheckedLiteral;
2518 return SLCT_NotALiteral;
2521 case Stmt::CallExprClass:
2522 case Stmt::CXXMemberCallExprClass: {
2523 const CallExpr *CE = cast<CallExpr>(E);
2524 if (const NamedDecl *ND = dyn_cast_or_null<NamedDecl>(CE->getCalleeDecl())) {
2525 if (const FormatArgAttr *FA = ND->getAttr<FormatArgAttr>()) {
2526 unsigned ArgIndex = FA->getFormatIdx();
2527 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(ND))
2528 if (MD->isInstance())
2530 const Expr *Arg = CE->getArg(ArgIndex - 1);
2532 return checkFormatStringExpr(S, Arg, Args,
2533 HasVAListArg, format_idx, firstDataArg,
2534 Type, CallType, InFunctionCall,
2536 } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) {
2537 unsigned BuiltinID = FD->getBuiltinID();
2538 if (BuiltinID == Builtin::BI__builtin___CFStringMakeConstantString ||
2539 BuiltinID == Builtin::BI__builtin___NSStringMakeConstantString) {
2540 const Expr *Arg = CE->getArg(0);
2541 return checkFormatStringExpr(S, Arg, Args,
2542 HasVAListArg, format_idx,
2543 firstDataArg, Type, CallType,
2544 InFunctionCall, CheckedVarArgs);
2549 return SLCT_NotALiteral;
2551 case Stmt::ObjCStringLiteralClass:
2552 case Stmt::StringLiteralClass: {
2553 const StringLiteral *StrE = nullptr;
2555 if (const ObjCStringLiteral *ObjCFExpr = dyn_cast<ObjCStringLiteral>(E))
2556 StrE = ObjCFExpr->getString();
2558 StrE = cast<StringLiteral>(E);
2561 S.CheckFormatString(StrE, E, Args, HasVAListArg, format_idx, firstDataArg,
2562 Type, InFunctionCall, CallType, CheckedVarArgs);
2563 return SLCT_CheckedLiteral;
2566 return SLCT_NotALiteral;
2570 return SLCT_NotALiteral;
2574 Sema::FormatStringType Sema::GetFormatStringType(const FormatAttr *Format) {
2575 return llvm::StringSwitch<FormatStringType>(Format->getType()->getName())
2576 .Case("scanf", FST_Scanf)
2577 .Cases("printf", "printf0", FST_Printf)
2578 .Cases("NSString", "CFString", FST_NSString)
2579 .Case("strftime", FST_Strftime)
2580 .Case("strfmon", FST_Strfmon)
2581 .Cases("kprintf", "cmn_err", "vcmn_err", "zcmn_err", FST_Kprintf)
2582 .Default(FST_Unknown);
2585 /// CheckFormatArguments - Check calls to printf and scanf (and similar
2586 /// functions) for correct use of format strings.
2587 /// Returns true if a format string has been fully checked.
2588 bool Sema::CheckFormatArguments(const FormatAttr *Format,
2589 ArrayRef<const Expr *> Args,
2591 VariadicCallType CallType,
2592 SourceLocation Loc, SourceRange Range,
2593 llvm::SmallBitVector &CheckedVarArgs) {
2594 FormatStringInfo FSI;
2595 if (getFormatStringInfo(Format, IsCXXMember, &FSI))
2596 return CheckFormatArguments(Args, FSI.HasVAListArg, FSI.FormatIdx,
2597 FSI.FirstDataArg, GetFormatStringType(Format),
2598 CallType, Loc, Range, CheckedVarArgs);
2602 bool Sema::CheckFormatArguments(ArrayRef<const Expr *> Args,
2603 bool HasVAListArg, unsigned format_idx,
2604 unsigned firstDataArg, FormatStringType Type,
2605 VariadicCallType CallType,
2606 SourceLocation Loc, SourceRange Range,
2607 llvm::SmallBitVector &CheckedVarArgs) {
2608 // CHECK: printf/scanf-like function is called with no format string.
2609 if (format_idx >= Args.size()) {
2610 Diag(Loc, diag::warn_missing_format_string) << Range;
2614 const Expr *OrigFormatExpr = Args[format_idx]->IgnoreParenCasts();
2616 // CHECK: format string is not a string literal.
2618 // Dynamically generated format strings are difficult to
2619 // automatically vet at compile time. Requiring that format strings
2620 // are string literals: (1) permits the checking of format strings by
2621 // the compiler and thereby (2) can practically remove the source of
2622 // many format string exploits.
2624 // Format string can be either ObjC string (e.g. @"%d") or
2625 // C string (e.g. "%d")
2626 // ObjC string uses the same format specifiers as C string, so we can use
2627 // the same format string checking logic for both ObjC and C strings.
2628 StringLiteralCheckType CT =
2629 checkFormatStringExpr(*this, OrigFormatExpr, Args, HasVAListArg,
2630 format_idx, firstDataArg, Type, CallType,
2631 /*IsFunctionCall*/true, CheckedVarArgs);
2632 if (CT != SLCT_NotALiteral)
2633 // Literal format string found, check done!
2634 return CT == SLCT_CheckedLiteral;
2636 // Strftime is particular as it always uses a single 'time' argument,
2637 // so it is safe to pass a non-literal string.
2638 if (Type == FST_Strftime)
2641 // Do not emit diag when the string param is a macro expansion and the
2642 // format is either NSString or CFString. This is a hack to prevent
2643 // diag when using the NSLocalizedString and CFCopyLocalizedString macros
2644 // which are usually used in place of NS and CF string literals.
2645 if (Type == FST_NSString &&
2646 SourceMgr.isInSystemMacro(Args[format_idx]->getLocStart()))
2649 // If there are no arguments specified, warn with -Wformat-security, otherwise
2650 // warn only with -Wformat-nonliteral.
2651 if (Args.size() == firstDataArg)
2652 Diag(Args[format_idx]->getLocStart(),
2653 diag::warn_format_nonliteral_noargs)
2654 << OrigFormatExpr->getSourceRange();
2656 Diag(Args[format_idx]->getLocStart(),
2657 diag::warn_format_nonliteral)
2658 << OrigFormatExpr->getSourceRange();
2663 class CheckFormatHandler : public analyze_format_string::FormatStringHandler {
2666 const StringLiteral *FExpr;
2667 const Expr *OrigFormatExpr;
2668 const unsigned FirstDataArg;
2669 const unsigned NumDataArgs;
2670 const char *Beg; // Start of format string.
2671 const bool HasVAListArg;
2672 ArrayRef<const Expr *> Args;
2674 llvm::SmallBitVector CoveredArgs;
2675 bool usesPositionalArgs;
2677 bool inFunctionCall;
2678 Sema::VariadicCallType CallType;
2679 llvm::SmallBitVector &CheckedVarArgs;
2681 CheckFormatHandler(Sema &s, const StringLiteral *fexpr,
2682 const Expr *origFormatExpr, unsigned firstDataArg,
2683 unsigned numDataArgs, const char *beg, bool hasVAListArg,
2684 ArrayRef<const Expr *> Args,
2685 unsigned formatIdx, bool inFunctionCall,
2686 Sema::VariadicCallType callType,
2687 llvm::SmallBitVector &CheckedVarArgs)
2688 : S(s), FExpr(fexpr), OrigFormatExpr(origFormatExpr),
2689 FirstDataArg(firstDataArg), NumDataArgs(numDataArgs),
2690 Beg(beg), HasVAListArg(hasVAListArg),
2691 Args(Args), FormatIdx(formatIdx),
2692 usesPositionalArgs(false), atFirstArg(true),
2693 inFunctionCall(inFunctionCall), CallType(callType),
2694 CheckedVarArgs(CheckedVarArgs) {
2695 CoveredArgs.resize(numDataArgs);
2696 CoveredArgs.reset();
2699 void DoneProcessing();
2701 void HandleIncompleteSpecifier(const char *startSpecifier,
2702 unsigned specifierLen) override;
2704 void HandleInvalidLengthModifier(
2705 const analyze_format_string::FormatSpecifier &FS,
2706 const analyze_format_string::ConversionSpecifier &CS,
2707 const char *startSpecifier, unsigned specifierLen,
2710 void HandleNonStandardLengthModifier(
2711 const analyze_format_string::FormatSpecifier &FS,
2712 const char *startSpecifier, unsigned specifierLen);
2714 void HandleNonStandardConversionSpecifier(
2715 const analyze_format_string::ConversionSpecifier &CS,
2716 const char *startSpecifier, unsigned specifierLen);
2718 void HandlePosition(const char *startPos, unsigned posLen) override;
2720 void HandleInvalidPosition(const char *startSpecifier,
2721 unsigned specifierLen,
2722 analyze_format_string::PositionContext p) override;
2724 void HandleZeroPosition(const char *startPos, unsigned posLen) override;
2726 void HandleNullChar(const char *nullCharacter) override;
2728 template <typename Range>
2729 static void EmitFormatDiagnostic(Sema &S, bool inFunctionCall,
2730 const Expr *ArgumentExpr,
2731 PartialDiagnostic PDiag,
2732 SourceLocation StringLoc,
2733 bool IsStringLocation, Range StringRange,
2734 ArrayRef<FixItHint> Fixit = None);
2737 bool HandleInvalidConversionSpecifier(unsigned argIndex, SourceLocation Loc,
2738 const char *startSpec,
2739 unsigned specifierLen,
2740 const char *csStart, unsigned csLen);
2742 void HandlePositionalNonpositionalArgs(SourceLocation Loc,
2743 const char *startSpec,
2744 unsigned specifierLen);
2746 SourceRange getFormatStringRange();
2747 CharSourceRange getSpecifierRange(const char *startSpecifier,
2748 unsigned specifierLen);
2749 SourceLocation getLocationOfByte(const char *x);
2751 const Expr *getDataArg(unsigned i) const;
2753 bool CheckNumArgs(const analyze_format_string::FormatSpecifier &FS,
2754 const analyze_format_string::ConversionSpecifier &CS,
2755 const char *startSpecifier, unsigned specifierLen,
2758 template <typename Range>
2759 void EmitFormatDiagnostic(PartialDiagnostic PDiag, SourceLocation StringLoc,
2760 bool IsStringLocation, Range StringRange,
2761 ArrayRef<FixItHint> Fixit = None);
2765 SourceRange CheckFormatHandler::getFormatStringRange() {
2766 return OrigFormatExpr->getSourceRange();
2769 CharSourceRange CheckFormatHandler::
2770 getSpecifierRange(const char *startSpecifier, unsigned specifierLen) {
2771 SourceLocation Start = getLocationOfByte(startSpecifier);
2772 SourceLocation End = getLocationOfByte(startSpecifier + specifierLen - 1);
2774 // Advance the end SourceLocation by one due to half-open ranges.
2775 End = End.getLocWithOffset(1);
2777 return CharSourceRange::getCharRange(Start, End);
2780 SourceLocation CheckFormatHandler::getLocationOfByte(const char *x) {
2781 return S.getLocationOfStringLiteralByte(FExpr, x - Beg);
2784 void CheckFormatHandler::HandleIncompleteSpecifier(const char *startSpecifier,
2785 unsigned specifierLen){
2786 EmitFormatDiagnostic(S.PDiag(diag::warn_printf_incomplete_specifier),
2787 getLocationOfByte(startSpecifier),
2788 /*IsStringLocation*/true,
2789 getSpecifierRange(startSpecifier, specifierLen));
2792 void CheckFormatHandler::HandleInvalidLengthModifier(
2793 const analyze_format_string::FormatSpecifier &FS,
2794 const analyze_format_string::ConversionSpecifier &CS,
2795 const char *startSpecifier, unsigned specifierLen, unsigned DiagID) {
2796 using namespace analyze_format_string;
2798 const LengthModifier &LM = FS.getLengthModifier();
2799 CharSourceRange LMRange = getSpecifierRange(LM.getStart(), LM.getLength());
2801 // See if we know how to fix this length modifier.
2802 Optional<LengthModifier> FixedLM = FS.getCorrectedLengthModifier();
2804 EmitFormatDiagnostic(S.PDiag(DiagID) << LM.toString() << CS.toString(),
2805 getLocationOfByte(LM.getStart()),
2806 /*IsStringLocation*/true,
2807 getSpecifierRange(startSpecifier, specifierLen));
2809 S.Diag(getLocationOfByte(LM.getStart()), diag::note_format_fix_specifier)
2810 << FixedLM->toString()
2811 << FixItHint::CreateReplacement(LMRange, FixedLM->toString());
2815 if (DiagID == diag::warn_format_nonsensical_length)
2816 Hint = FixItHint::CreateRemoval(LMRange);
2818 EmitFormatDiagnostic(S.PDiag(DiagID) << LM.toString() << CS.toString(),
2819 getLocationOfByte(LM.getStart()),
2820 /*IsStringLocation*/true,
2821 getSpecifierRange(startSpecifier, specifierLen),
2826 void CheckFormatHandler::HandleNonStandardLengthModifier(
2827 const analyze_format_string::FormatSpecifier &FS,
2828 const char *startSpecifier, unsigned specifierLen) {
2829 using namespace analyze_format_string;
2831 const LengthModifier &LM = FS.getLengthModifier();
2832 CharSourceRange LMRange = getSpecifierRange(LM.getStart(), LM.getLength());
2834 // See if we know how to fix this length modifier.
2835 Optional<LengthModifier> FixedLM = FS.getCorrectedLengthModifier();
2837 EmitFormatDiagnostic(S.PDiag(diag::warn_format_non_standard)
2838 << LM.toString() << 0,
2839 getLocationOfByte(LM.getStart()),
2840 /*IsStringLocation*/true,
2841 getSpecifierRange(startSpecifier, specifierLen));
2843 S.Diag(getLocationOfByte(LM.getStart()), diag::note_format_fix_specifier)
2844 << FixedLM->toString()
2845 << FixItHint::CreateReplacement(LMRange, FixedLM->toString());
2848 EmitFormatDiagnostic(S.PDiag(diag::warn_format_non_standard)
2849 << LM.toString() << 0,
2850 getLocationOfByte(LM.getStart()),
2851 /*IsStringLocation*/true,
2852 getSpecifierRange(startSpecifier, specifierLen));
2856 void CheckFormatHandler::HandleNonStandardConversionSpecifier(
2857 const analyze_format_string::ConversionSpecifier &CS,
2858 const char *startSpecifier, unsigned specifierLen) {
2859 using namespace analyze_format_string;
2861 // See if we know how to fix this conversion specifier.
2862 Optional<ConversionSpecifier> FixedCS = CS.getStandardSpecifier();
2864 EmitFormatDiagnostic(S.PDiag(diag::warn_format_non_standard)
2865 << CS.toString() << /*conversion specifier*/1,
2866 getLocationOfByte(CS.getStart()),
2867 /*IsStringLocation*/true,
2868 getSpecifierRange(startSpecifier, specifierLen));
2870 CharSourceRange CSRange = getSpecifierRange(CS.getStart(), CS.getLength());
2871 S.Diag(getLocationOfByte(CS.getStart()), diag::note_format_fix_specifier)
2872 << FixedCS->toString()
2873 << FixItHint::CreateReplacement(CSRange, FixedCS->toString());
2875 EmitFormatDiagnostic(S.PDiag(diag::warn_format_non_standard)
2876 << CS.toString() << /*conversion specifier*/1,
2877 getLocationOfByte(CS.getStart()),
2878 /*IsStringLocation*/true,
2879 getSpecifierRange(startSpecifier, specifierLen));
2883 void CheckFormatHandler::HandlePosition(const char *startPos,
2885 EmitFormatDiagnostic(S.PDiag(diag::warn_format_non_standard_positional_arg),
2886 getLocationOfByte(startPos),
2887 /*IsStringLocation*/true,
2888 getSpecifierRange(startPos, posLen));
2892 CheckFormatHandler::HandleInvalidPosition(const char *startPos, unsigned posLen,
2893 analyze_format_string::PositionContext p) {
2894 EmitFormatDiagnostic(S.PDiag(diag::warn_format_invalid_positional_specifier)
2896 getLocationOfByte(startPos), /*IsStringLocation*/true,
2897 getSpecifierRange(startPos, posLen));
2900 void CheckFormatHandler::HandleZeroPosition(const char *startPos,
2902 EmitFormatDiagnostic(S.PDiag(diag::warn_format_zero_positional_specifier),
2903 getLocationOfByte(startPos),
2904 /*IsStringLocation*/true,
2905 getSpecifierRange(startPos, posLen));
2908 void CheckFormatHandler::HandleNullChar(const char *nullCharacter) {
2909 if (!isa<ObjCStringLiteral>(OrigFormatExpr)) {
2910 // The presence of a null character is likely an error.
2911 EmitFormatDiagnostic(
2912 S.PDiag(diag::warn_printf_format_string_contains_null_char),
2913 getLocationOfByte(nullCharacter), /*IsStringLocation*/true,
2914 getFormatStringRange());
2918 // Note that this may return NULL if there was an error parsing or building
2919 // one of the argument expressions.
2920 const Expr *CheckFormatHandler::getDataArg(unsigned i) const {
2921 return Args[FirstDataArg + i];
2924 void CheckFormatHandler::DoneProcessing() {
2925 // Does the number of data arguments exceed the number of
2926 // format conversions in the format string?
2927 if (!HasVAListArg) {
2928 // Find any arguments that weren't covered.
2930 signed notCoveredArg = CoveredArgs.find_first();
2931 if (notCoveredArg >= 0) {
2932 assert((unsigned)notCoveredArg < NumDataArgs);
2933 if (const Expr *E = getDataArg((unsigned) notCoveredArg)) {
2934 SourceLocation Loc = E->getLocStart();
2935 if (!S.getSourceManager().isInSystemMacro(Loc)) {
2936 EmitFormatDiagnostic(S.PDiag(diag::warn_printf_data_arg_not_used),
2937 Loc, /*IsStringLocation*/false,
2938 getFormatStringRange());
2946 CheckFormatHandler::HandleInvalidConversionSpecifier(unsigned argIndex,
2948 const char *startSpec,
2949 unsigned specifierLen,
2950 const char *csStart,
2953 bool keepGoing = true;
2954 if (argIndex < NumDataArgs) {
2955 // Consider the argument coverered, even though the specifier doesn't
2957 CoveredArgs.set(argIndex);
2960 // If argIndex exceeds the number of data arguments we
2961 // don't issue a warning because that is just a cascade of warnings (and
2962 // they may have intended '%%' anyway). We don't want to continue processing
2963 // the format string after this point, however, as we will like just get
2964 // gibberish when trying to match arguments.
2968 EmitFormatDiagnostic(S.PDiag(diag::warn_format_invalid_conversion)
2969 << StringRef(csStart, csLen),
2970 Loc, /*IsStringLocation*/true,
2971 getSpecifierRange(startSpec, specifierLen));
2977 CheckFormatHandler::HandlePositionalNonpositionalArgs(SourceLocation Loc,
2978 const char *startSpec,
2979 unsigned specifierLen) {
2980 EmitFormatDiagnostic(
2981 S.PDiag(diag::warn_format_mix_positional_nonpositional_args),
2982 Loc, /*isStringLoc*/true, getSpecifierRange(startSpec, specifierLen));
2986 CheckFormatHandler::CheckNumArgs(
2987 const analyze_format_string::FormatSpecifier &FS,
2988 const analyze_format_string::ConversionSpecifier &CS,
2989 const char *startSpecifier, unsigned specifierLen, unsigned argIndex) {
2991 if (argIndex >= NumDataArgs) {
2992 PartialDiagnostic PDiag = FS.usesPositionalArg()
2993 ? (S.PDiag(diag::warn_printf_positional_arg_exceeds_data_args)
2994 << (argIndex+1) << NumDataArgs)
2995 : S.PDiag(diag::warn_printf_insufficient_data_args);
2996 EmitFormatDiagnostic(
2997 PDiag, getLocationOfByte(CS.getStart()), /*IsStringLocation*/true,
2998 getSpecifierRange(startSpecifier, specifierLen));
3004 template<typename Range>
3005 void CheckFormatHandler::EmitFormatDiagnostic(PartialDiagnostic PDiag,
3007 bool IsStringLocation,
3009 ArrayRef<FixItHint> FixIt) {
3010 EmitFormatDiagnostic(S, inFunctionCall, Args[FormatIdx], PDiag,
3011 Loc, IsStringLocation, StringRange, FixIt);
3014 /// \brief If the format string is not within the funcion call, emit a note
3015 /// so that the function call and string are in diagnostic messages.
3017 /// \param InFunctionCall if true, the format string is within the function
3018 /// call and only one diagnostic message will be produced. Otherwise, an
3019 /// extra note will be emitted pointing to location of the format string.
3021 /// \param ArgumentExpr the expression that is passed as the format string
3022 /// argument in the function call. Used for getting locations when two
3023 /// diagnostics are emitted.
3025 /// \param PDiag the callee should already have provided any strings for the
3026 /// diagnostic message. This function only adds locations and fixits
3029 /// \param Loc primary location for diagnostic. If two diagnostics are
3030 /// required, one will be at Loc and a new SourceLocation will be created for
3033 /// \param IsStringLocation if true, Loc points to the format string should be
3034 /// used for the note. Otherwise, Loc points to the argument list and will
3035 /// be used with PDiag.
3037 /// \param StringRange some or all of the string to highlight. This is
3038 /// templated so it can accept either a CharSourceRange or a SourceRange.
3040 /// \param FixIt optional fix it hint for the format string.
3041 template<typename Range>
3042 void CheckFormatHandler::EmitFormatDiagnostic(Sema &S, bool InFunctionCall,
3043 const Expr *ArgumentExpr,
3044 PartialDiagnostic PDiag,
3046 bool IsStringLocation,
3048 ArrayRef<FixItHint> FixIt) {
3049 if (InFunctionCall) {
3050 const Sema::SemaDiagnosticBuilder &D = S.Diag(Loc, PDiag);
3052 for (ArrayRef<FixItHint>::iterator I = FixIt.begin(), E = FixIt.end();
3057 S.Diag(IsStringLocation ? ArgumentExpr->getExprLoc() : Loc, PDiag)
3058 << ArgumentExpr->getSourceRange();
3060 const Sema::SemaDiagnosticBuilder &Note =
3061 S.Diag(IsStringLocation ? Loc : StringRange.getBegin(),
3062 diag::note_format_string_defined);
3064 Note << StringRange;
3065 for (ArrayRef<FixItHint>::iterator I = FixIt.begin(), E = FixIt.end();
3072 //===--- CHECK: Printf format string checking ------------------------------===//
3075 class CheckPrintfHandler : public CheckFormatHandler {
3078 CheckPrintfHandler(Sema &s, const StringLiteral *fexpr,
3079 const Expr *origFormatExpr, unsigned firstDataArg,
3080 unsigned numDataArgs, bool isObjC,
3081 const char *beg, bool hasVAListArg,
3082 ArrayRef<const Expr *> Args,
3083 unsigned formatIdx, bool inFunctionCall,
3084 Sema::VariadicCallType CallType,
3085 llvm::SmallBitVector &CheckedVarArgs)
3086 : CheckFormatHandler(s, fexpr, origFormatExpr, firstDataArg,
3087 numDataArgs, beg, hasVAListArg, Args,
3088 formatIdx, inFunctionCall, CallType, CheckedVarArgs),
3093 bool HandleInvalidPrintfConversionSpecifier(
3094 const analyze_printf::PrintfSpecifier &FS,
3095 const char *startSpecifier,
3096 unsigned specifierLen) override;
3098 bool HandlePrintfSpecifier(const analyze_printf::PrintfSpecifier &FS,
3099 const char *startSpecifier,
3100 unsigned specifierLen) override;
3101 bool checkFormatExpr(const analyze_printf::PrintfSpecifier &FS,
3102 const char *StartSpecifier,
3103 unsigned SpecifierLen,
3106 bool HandleAmount(const analyze_format_string::OptionalAmount &Amt, unsigned k,
3107 const char *startSpecifier, unsigned specifierLen);
3108 void HandleInvalidAmount(const analyze_printf::PrintfSpecifier &FS,
3109 const analyze_printf::OptionalAmount &Amt,
3111 const char *startSpecifier, unsigned specifierLen);
3112 void HandleFlag(const analyze_printf::PrintfSpecifier &FS,
3113 const analyze_printf::OptionalFlag &flag,
3114 const char *startSpecifier, unsigned specifierLen);
3115 void HandleIgnoredFlag(const analyze_printf::PrintfSpecifier &FS,
3116 const analyze_printf::OptionalFlag &ignoredFlag,
3117 const analyze_printf::OptionalFlag &flag,
3118 const char *startSpecifier, unsigned specifierLen);
3119 bool checkForCStrMembers(const analyze_printf::ArgType &AT,
3125 bool CheckPrintfHandler::HandleInvalidPrintfConversionSpecifier(
3126 const analyze_printf::PrintfSpecifier &FS,
3127 const char *startSpecifier,
3128 unsigned specifierLen) {
3129 const analyze_printf::PrintfConversionSpecifier &CS =
3130 FS.getConversionSpecifier();
3132 return HandleInvalidConversionSpecifier(FS.getArgIndex(),
3133 getLocationOfByte(CS.getStart()),
3134 startSpecifier, specifierLen,
3135 CS.getStart(), CS.getLength());
3138 bool CheckPrintfHandler::HandleAmount(
3139 const analyze_format_string::OptionalAmount &Amt,
3140 unsigned k, const char *startSpecifier,
3141 unsigned specifierLen) {
3143 if (Amt.hasDataArgument()) {
3144 if (!HasVAListArg) {
3145 unsigned argIndex = Amt.getArgIndex();
3146 if (argIndex >= NumDataArgs) {
3147 EmitFormatDiagnostic(S.PDiag(diag::warn_printf_asterisk_missing_arg)
3149 getLocationOfByte(Amt.getStart()),
3150 /*IsStringLocation*/true,
3151 getSpecifierRange(startSpecifier, specifierLen));
3152 // Don't do any more checking. We will just emit
3157 // Type check the data argument. It should be an 'int'.
3158 // Although not in conformance with C99, we also allow the argument to be
3159 // an 'unsigned int' as that is a reasonably safe case. GCC also
3160 // doesn't emit a warning for that case.
3161 CoveredArgs.set(argIndex);
3162 const Expr *Arg = getDataArg(argIndex);
3166 QualType T = Arg->getType();
3168 const analyze_printf::ArgType &AT = Amt.getArgType(S.Context);
3169 assert(AT.isValid());
3171 if (!AT.matchesType(S.Context, T)) {
3172 EmitFormatDiagnostic(S.PDiag(diag::warn_printf_asterisk_wrong_type)
3173 << k << AT.getRepresentativeTypeName(S.Context)
3174 << T << Arg->getSourceRange(),
3175 getLocationOfByte(Amt.getStart()),
3176 /*IsStringLocation*/true,
3177 getSpecifierRange(startSpecifier, specifierLen));
3178 // Don't do any more checking. We will just emit
3187 void CheckPrintfHandler::HandleInvalidAmount(
3188 const analyze_printf::PrintfSpecifier &FS,
3189 const analyze_printf::OptionalAmount &Amt,
3191 const char *startSpecifier,
3192 unsigned specifierLen) {
3193 const analyze_printf::PrintfConversionSpecifier &CS =
3194 FS.getConversionSpecifier();
3197 Amt.getHowSpecified() == analyze_printf::OptionalAmount::Constant
3198 ? FixItHint::CreateRemoval(getSpecifierRange(Amt.getStart(),
3199 Amt.getConstantLength()))
3202 EmitFormatDiagnostic(S.PDiag(diag::warn_printf_nonsensical_optional_amount)
3203 << type << CS.toString(),
3204 getLocationOfByte(Amt.getStart()),
3205 /*IsStringLocation*/true,
3206 getSpecifierRange(startSpecifier, specifierLen),
3210 void CheckPrintfHandler::HandleFlag(const analyze_printf::PrintfSpecifier &FS,
3211 const analyze_printf::OptionalFlag &flag,
3212 const char *startSpecifier,
3213 unsigned specifierLen) {
3214 // Warn about pointless flag with a fixit removal.
3215 const analyze_printf::PrintfConversionSpecifier &CS =
3216 FS.getConversionSpecifier();
3217 EmitFormatDiagnostic(S.PDiag(diag::warn_printf_nonsensical_flag)
3218 << flag.toString() << CS.toString(),
3219 getLocationOfByte(flag.getPosition()),
3220 /*IsStringLocation*/true,
3221 getSpecifierRange(startSpecifier, specifierLen),
3222 FixItHint::CreateRemoval(
3223 getSpecifierRange(flag.getPosition(), 1)));
3226 void CheckPrintfHandler::HandleIgnoredFlag(
3227 const analyze_printf::PrintfSpecifier &FS,
3228 const analyze_printf::OptionalFlag &ignoredFlag,
3229 const analyze_printf::OptionalFlag &flag,
3230 const char *startSpecifier,
3231 unsigned specifierLen) {
3232 // Warn about ignored flag with a fixit removal.
3233 EmitFormatDiagnostic(S.PDiag(diag::warn_printf_ignored_flag)
3234 << ignoredFlag.toString() << flag.toString(),
3235 getLocationOfByte(ignoredFlag.getPosition()),
3236 /*IsStringLocation*/true,
3237 getSpecifierRange(startSpecifier, specifierLen),
3238 FixItHint::CreateRemoval(
3239 getSpecifierRange(ignoredFlag.getPosition(), 1)));
3242 // Determines if the specified is a C++ class or struct containing
3243 // a member with the specified name and kind (e.g. a CXXMethodDecl named
3245 template<typename MemberKind>
3246 static llvm::SmallPtrSet<MemberKind*, 1>
3247 CXXRecordMembersNamed(StringRef Name, Sema &S, QualType Ty) {
3248 const RecordType *RT = Ty->getAs<RecordType>();
3249 llvm::SmallPtrSet<MemberKind*, 1> Results;
3253 const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl());
3254 if (!RD || !RD->getDefinition())
3257 LookupResult R(S, &S.Context.Idents.get(Name), SourceLocation(),
3258 Sema::LookupMemberName);
3259 R.suppressDiagnostics();
3261 // We just need to include all members of the right kind turned up by the
3262 // filter, at this point.
3263 if (S.LookupQualifiedName(R, RT->getDecl()))
3264 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) {
3265 NamedDecl *decl = (*I)->getUnderlyingDecl();
3266 if (MemberKind *FK = dyn_cast<MemberKind>(decl))
3272 /// Check if we could call '.c_str()' on an object.
3274 /// FIXME: This returns the wrong results in some cases (if cv-qualifiers don't
3275 /// allow the call, or if it would be ambiguous).
3276 bool Sema::hasCStrMethod(const Expr *E) {
3277 typedef llvm::SmallPtrSet<CXXMethodDecl*, 1> MethodSet;
3279 CXXRecordMembersNamed<CXXMethodDecl>("c_str", *this, E->getType());
3280 for (MethodSet::iterator MI = Results.begin(), ME = Results.end();
3282 if ((*MI)->getMinRequiredArguments() == 0)
3287 // Check if a (w)string was passed when a (w)char* was needed, and offer a
3288 // better diagnostic if so. AT is assumed to be valid.
3289 // Returns true when a c_str() conversion method is found.
3290 bool CheckPrintfHandler::checkForCStrMembers(
3291 const analyze_printf::ArgType &AT, const Expr *E) {
3292 typedef llvm::SmallPtrSet<CXXMethodDecl*, 1> MethodSet;
3295 CXXRecordMembersNamed<CXXMethodDecl>("c_str", S, E->getType());
3297 for (MethodSet::iterator MI = Results.begin(), ME = Results.end();
3299 const CXXMethodDecl *Method = *MI;
3300 if (Method->getMinRequiredArguments() == 0 &&
3301 AT.matchesType(S.Context, Method->getReturnType())) {
3302 // FIXME: Suggest parens if the expression needs them.
3303 SourceLocation EndLoc = S.getLocForEndOfToken(E->getLocEnd());
3304 S.Diag(E->getLocStart(), diag::note_printf_c_str)
3306 << FixItHint::CreateInsertion(EndLoc, ".c_str()");
3315 CheckPrintfHandler::HandlePrintfSpecifier(const analyze_printf::PrintfSpecifier
3317 const char *startSpecifier,
3318 unsigned specifierLen) {
3320 using namespace analyze_format_string;
3321 using namespace analyze_printf;
3322 const PrintfConversionSpecifier &CS = FS.getConversionSpecifier();
3324 if (FS.consumesDataArgument()) {
3327 usesPositionalArgs = FS.usesPositionalArg();
3329 else if (usesPositionalArgs != FS.usesPositionalArg()) {
3330 HandlePositionalNonpositionalArgs(getLocationOfByte(CS.getStart()),
3331 startSpecifier, specifierLen);
3336 // First check if the field width, precision, and conversion specifier
3337 // have matching data arguments.
3338 if (!HandleAmount(FS.getFieldWidth(), /* field width */ 0,
3339 startSpecifier, specifierLen)) {
3343 if (!HandleAmount(FS.getPrecision(), /* precision */ 1,
3344 startSpecifier, specifierLen)) {
3348 if (!CS.consumesDataArgument()) {
3349 // FIXME: Technically specifying a precision or field width here
3350 // makes no sense. Worth issuing a warning at some point.
3354 // Consume the argument.
3355 unsigned argIndex = FS.getArgIndex();
3356 if (argIndex < NumDataArgs) {
3357 // The check to see if the argIndex is valid will come later.
3358 // We set the bit here because we may exit early from this
3359 // function if we encounter some other error.
3360 CoveredArgs.set(argIndex);
3363 // Check for using an Objective-C specific conversion specifier
3364 // in a non-ObjC literal.
3365 if (!ObjCContext && CS.isObjCArg()) {
3366 return HandleInvalidPrintfConversionSpecifier(FS, startSpecifier,
3370 // Check for invalid use of field width
3371 if (!FS.hasValidFieldWidth()) {
3372 HandleInvalidAmount(FS, FS.getFieldWidth(), /* field width */ 0,
3373 startSpecifier, specifierLen);
3376 // Check for invalid use of precision
3377 if (!FS.hasValidPrecision()) {
3378 HandleInvalidAmount(FS, FS.getPrecision(), /* precision */ 1,
3379 startSpecifier, specifierLen);
3382 // Check each flag does not conflict with any other component.
3383 if (!FS.hasValidThousandsGroupingPrefix())
3384 HandleFlag(FS, FS.hasThousandsGrouping(), startSpecifier, specifierLen);
3385 if (!FS.hasValidLeadingZeros())
3386 HandleFlag(FS, FS.hasLeadingZeros(), startSpecifier, specifierLen);
3387 if (!FS.hasValidPlusPrefix())
3388 HandleFlag(FS, FS.hasPlusPrefix(), startSpecifier, specifierLen);
3389 if (!FS.hasValidSpacePrefix())
3390 HandleFlag(FS, FS.hasSpacePrefix(), startSpecifier, specifierLen);
3391 if (!FS.hasValidAlternativeForm())
3392 HandleFlag(FS, FS.hasAlternativeForm(), startSpecifier, specifierLen);
3393 if (!FS.hasValidLeftJustified())
3394 HandleFlag(FS, FS.isLeftJustified(), startSpecifier, specifierLen);
3396 // Check that flags are not ignored by another flag
3397 if (FS.hasSpacePrefix() && FS.hasPlusPrefix()) // ' ' ignored by '+'
3398 HandleIgnoredFlag(FS, FS.hasSpacePrefix(), FS.hasPlusPrefix(),
3399 startSpecifier, specifierLen);
3400 if (FS.hasLeadingZeros() && FS.isLeftJustified()) // '0' ignored by '-'
3401 HandleIgnoredFlag(FS, FS.hasLeadingZeros(), FS.isLeftJustified(),
3402 startSpecifier, specifierLen);
3404 // Check the length modifier is valid with the given conversion specifier.
3405 if (!FS.hasValidLengthModifier(S.getASTContext().getTargetInfo()))
3406 HandleInvalidLengthModifier(FS, CS, startSpecifier, specifierLen,
3407 diag::warn_format_nonsensical_length);
3408 else if (!FS.hasStandardLengthModifier())
3409 HandleNonStandardLengthModifier(FS, startSpecifier, specifierLen);
3410 else if (!FS.hasStandardLengthConversionCombination())
3411 HandleInvalidLengthModifier(FS, CS, startSpecifier, specifierLen,
3412 diag::warn_format_non_standard_conversion_spec);
3414 if (!FS.hasStandardConversionSpecifier(S.getLangOpts()))
3415 HandleNonStandardConversionSpecifier(CS, startSpecifier, specifierLen);
3417 // The remaining checks depend on the data arguments.
3421 if (!CheckNumArgs(FS, CS, startSpecifier, specifierLen, argIndex))
3424 const Expr *Arg = getDataArg(argIndex);
3428 return checkFormatExpr(FS, startSpecifier, specifierLen, Arg);
3431 static bool requiresParensToAddCast(const Expr *E) {
3432 // FIXME: We should have a general way to reason about operator
3433 // precedence and whether parens are actually needed here.
3434 // Take care of a few common cases where they aren't.
3435 const Expr *Inside = E->IgnoreImpCasts();
3436 if (const PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(Inside))
3437 Inside = POE->getSyntacticForm()->IgnoreImpCasts();
3439 switch (Inside->getStmtClass()) {
3440 case Stmt::ArraySubscriptExprClass:
3441 case Stmt::CallExprClass:
3442 case Stmt::CharacterLiteralClass:
3443 case Stmt::CXXBoolLiteralExprClass:
3444 case Stmt::DeclRefExprClass:
3445 case Stmt::FloatingLiteralClass:
3446 case Stmt::IntegerLiteralClass:
3447 case Stmt::MemberExprClass:
3448 case Stmt::ObjCArrayLiteralClass:
3449 case Stmt::ObjCBoolLiteralExprClass:
3450 case Stmt::ObjCBoxedExprClass:
3451 case Stmt::ObjCDictionaryLiteralClass:
3452 case Stmt::ObjCEncodeExprClass:
3453 case Stmt::ObjCIvarRefExprClass:
3454 case Stmt::ObjCMessageExprClass:
3455 case Stmt::ObjCPropertyRefExprClass:
3456 case Stmt::ObjCStringLiteralClass:
3457 case Stmt::ObjCSubscriptRefExprClass:
3458 case Stmt::ParenExprClass:
3459 case Stmt::StringLiteralClass:
3460 case Stmt::UnaryOperatorClass:
3467 static std::pair<QualType, StringRef>
3468 shouldNotPrintDirectly(const ASTContext &Context,
3469 QualType IntendedTy,
3471 // Use a 'while' to peel off layers of typedefs.
3472 QualType TyTy = IntendedTy;
3473 while (const TypedefType *UserTy = TyTy->getAs<TypedefType>()) {
3474 StringRef Name = UserTy->getDecl()->getName();
3475 QualType CastTy = llvm::StringSwitch<QualType>(Name)
3476 .Case("NSInteger", Context.LongTy)
3477 .Case("NSUInteger", Context.UnsignedLongTy)
3478 .Case("SInt32", Context.IntTy)
3479 .Case("UInt32", Context.UnsignedIntTy)
3480 .Default(QualType());
3482 if (!CastTy.isNull())
3483 return std::make_pair(CastTy, Name);
3485 TyTy = UserTy->desugar();
3488 // Strip parens if necessary.
3489 if (const ParenExpr *PE = dyn_cast<ParenExpr>(E))
3490 return shouldNotPrintDirectly(Context,
3491 PE->getSubExpr()->getType(),
3494 // If this is a conditional expression, then its result type is constructed
3495 // via usual arithmetic conversions and thus there might be no necessary
3496 // typedef sugar there. Recurse to operands to check for NSInteger &
3497 // Co. usage condition.
3498 if (const ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
3499 QualType TrueTy, FalseTy;
3500 StringRef TrueName, FalseName;
3502 std::tie(TrueTy, TrueName) =
3503 shouldNotPrintDirectly(Context,
3504 CO->getTrueExpr()->getType(),
3506 std::tie(FalseTy, FalseName) =
3507 shouldNotPrintDirectly(Context,
3508 CO->getFalseExpr()->getType(),
3509 CO->getFalseExpr());
3511 if (TrueTy == FalseTy)
3512 return std::make_pair(TrueTy, TrueName);
3513 else if (TrueTy.isNull())
3514 return std::make_pair(FalseTy, FalseName);
3515 else if (FalseTy.isNull())
3516 return std::make_pair(TrueTy, TrueName);
3519 return std::make_pair(QualType(), StringRef());
3523 CheckPrintfHandler::checkFormatExpr(const analyze_printf::PrintfSpecifier &FS,
3524 const char *StartSpecifier,
3525 unsigned SpecifierLen,
3527 using namespace analyze_format_string;
3528 using namespace analyze_printf;
3529 // Now type check the data expression that matches the
3530 // format specifier.
3531 const analyze_printf::ArgType &AT = FS.getArgType(S.Context,
3536 QualType ExprTy = E->getType();
3537 while (const TypeOfExprType *TET = dyn_cast<TypeOfExprType>(ExprTy)) {
3538 ExprTy = TET->getUnderlyingExpr()->getType();
3541 if (AT.matchesType(S.Context, ExprTy))
3544 // Look through argument promotions for our error message's reported type.
3545 // This includes the integral and floating promotions, but excludes array
3546 // and function pointer decay; seeing that an argument intended to be a
3547 // string has type 'char [6]' is probably more confusing than 'char *'.
3548 if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) {
3549 if (ICE->getCastKind() == CK_IntegralCast ||
3550 ICE->getCastKind() == CK_FloatingCast) {
3551 E = ICE->getSubExpr();
3552 ExprTy = E->getType();
3554 // Check if we didn't match because of an implicit cast from a 'char'
3555 // or 'short' to an 'int'. This is done because printf is a varargs
3557 if (ICE->getType() == S.Context.IntTy ||
3558 ICE->getType() == S.Context.UnsignedIntTy) {
3559 // All further checking is done on the subexpression.
3560 if (AT.matchesType(S.Context, ExprTy))
3564 } else if (const CharacterLiteral *CL = dyn_cast<CharacterLiteral>(E)) {
3565 // Special case for 'a', which has type 'int' in C.
3566 // Note, however, that we do /not/ want to treat multibyte constants like
3567 // 'MooV' as characters! This form is deprecated but still exists.
3568 if (ExprTy == S.Context.IntTy)
3569 if (llvm::isUIntN(S.Context.getCharWidth(), CL->getValue()))
3570 ExprTy = S.Context.CharTy;
3573 // Look through enums to their underlying type.
3574 bool IsEnum = false;
3575 if (auto EnumTy = ExprTy->getAs<EnumType>()) {
3576 ExprTy = EnumTy->getDecl()->getIntegerType();
3580 // %C in an Objective-C context prints a unichar, not a wchar_t.
3581 // If the argument is an integer of some kind, believe the %C and suggest
3582 // a cast instead of changing the conversion specifier.
3583 QualType IntendedTy = ExprTy;
3585 FS.getConversionSpecifier().getKind() == ConversionSpecifier::CArg) {
3586 if (ExprTy->isIntegralOrUnscopedEnumerationType() &&
3587 !ExprTy->isCharType()) {
3588 // 'unichar' is defined as a typedef of unsigned short, but we should
3589 // prefer using the typedef if it is visible.
3590 IntendedTy = S.Context.UnsignedShortTy;
3592 // While we are here, check if the value is an IntegerLiteral that happens
3593 // to be within the valid range.
3594 if (const IntegerLiteral *IL = dyn_cast<IntegerLiteral>(E)) {
3595 const llvm::APInt &V = IL->getValue();
3596 if (V.getActiveBits() <= S.Context.getTypeSize(IntendedTy))
3600 LookupResult Result(S, &S.Context.Idents.get("unichar"), E->getLocStart(),
3601 Sema::LookupOrdinaryName);
3602 if (S.LookupName(Result, S.getCurScope())) {
3603 NamedDecl *ND = Result.getFoundDecl();
3604 if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(ND))
3605 if (TD->getUnderlyingType() == IntendedTy)
3606 IntendedTy = S.Context.getTypedefType(TD);
3611 // Special-case some of Darwin's platform-independence types by suggesting
3612 // casts to primitive types that are known to be large enough.
3613 bool ShouldNotPrintDirectly = false; StringRef CastTyName;
3614 if (S.Context.getTargetInfo().getTriple().isOSDarwin()) {
3616 std::tie(CastTy, CastTyName) = shouldNotPrintDirectly(S.Context, IntendedTy, E);
3617 if (!CastTy.isNull()) {
3618 IntendedTy = CastTy;
3619 ShouldNotPrintDirectly = true;
3623 // We may be able to offer a FixItHint if it is a supported type.
3624 PrintfSpecifier fixedFS = FS;
3625 bool success = fixedFS.fixType(IntendedTy, S.getLangOpts(),
3626 S.Context, ObjCContext);
3629 // Get the fix string from the fixed format specifier
3630 SmallString<16> buf;
3631 llvm::raw_svector_ostream os(buf);
3632 fixedFS.toString(os);
3634 CharSourceRange SpecRange = getSpecifierRange(StartSpecifier, SpecifierLen);
3636 if (IntendedTy == ExprTy && !ShouldNotPrintDirectly) {
3637 // In this case, the specifier is wrong and should be changed to match
3639 EmitFormatDiagnostic(
3640 S.PDiag(diag::warn_format_conversion_argument_type_mismatch)
3641 << AT.getRepresentativeTypeName(S.Context) << IntendedTy << IsEnum
3642 << E->getSourceRange(),
3644 /*IsStringLocation*/false,
3646 FixItHint::CreateReplacement(SpecRange, os.str()));
3649 // The canonical type for formatting this value is different from the
3650 // actual type of the expression. (This occurs, for example, with Darwin's
3651 // NSInteger on 32-bit platforms, where it is typedef'd as 'int', but
3652 // should be printed as 'long' for 64-bit compatibility.)
3653 // Rather than emitting a normal format/argument mismatch, we want to
3654 // add a cast to the recommended type (and correct the format string
3656 SmallString<16> CastBuf;
3657 llvm::raw_svector_ostream CastFix(CastBuf);
3659 IntendedTy.print(CastFix, S.Context.getPrintingPolicy());
3662 SmallVector<FixItHint,4> Hints;
3663 if (!AT.matchesType(S.Context, IntendedTy))
3664 Hints.push_back(FixItHint::CreateReplacement(SpecRange, os.str()));
3666 if (const CStyleCastExpr *CCast = dyn_cast<CStyleCastExpr>(E)) {
3667 // If there's already a cast present, just replace it.
3668 SourceRange CastRange(CCast->getLParenLoc(), CCast->getRParenLoc());
3669 Hints.push_back(FixItHint::CreateReplacement(CastRange, CastFix.str()));
3671 } else if (!requiresParensToAddCast(E)) {
3672 // If the expression has high enough precedence,
3673 // just write the C-style cast.
3674 Hints.push_back(FixItHint::CreateInsertion(E->getLocStart(),
3677 // Otherwise, add parens around the expression as well as the cast.
3679 Hints.push_back(FixItHint::CreateInsertion(E->getLocStart(),
3682 SourceLocation After = S.getLocForEndOfToken(E->getLocEnd());
3683 Hints.push_back(FixItHint::CreateInsertion(After, ")"));
3686 if (ShouldNotPrintDirectly) {
3687 // The expression has a type that should not be printed directly.
3688 // We extract the name from the typedef because we don't want to show
3689 // the underlying type in the diagnostic.
3691 if (const TypedefType *TypedefTy = dyn_cast<TypedefType>(ExprTy))
3692 Name = TypedefTy->getDecl()->getName();
3695 EmitFormatDiagnostic(S.PDiag(diag::warn_format_argument_needs_cast)
3696 << Name << IntendedTy << IsEnum
3697 << E->getSourceRange(),
3698 E->getLocStart(), /*IsStringLocation=*/false,
3701 // In this case, the expression could be printed using a different
3702 // specifier, but we've decided that the specifier is probably correct
3703 // and we should cast instead. Just use the normal warning message.
3704 EmitFormatDiagnostic(
3705 S.PDiag(diag::warn_format_conversion_argument_type_mismatch)
3706 << AT.getRepresentativeTypeName(S.Context) << ExprTy << IsEnum
3707 << E->getSourceRange(),
3708 E->getLocStart(), /*IsStringLocation*/false,
3713 const CharSourceRange &CSR = getSpecifierRange(StartSpecifier,
3715 // Since the warning for passing non-POD types to variadic functions
3716 // was deferred until now, we emit a warning for non-POD
3718 switch (S.isValidVarArgType(ExprTy)) {
3719 case Sema::VAK_Valid:
3720 case Sema::VAK_ValidInCXX11:
3721 EmitFormatDiagnostic(
3722 S.PDiag(diag::warn_format_conversion_argument_type_mismatch)
3723 << AT.getRepresentativeTypeName(S.Context) << ExprTy << IsEnum
3725 << E->getSourceRange(),
3726 E->getLocStart(), /*IsStringLocation*/false, CSR);
3729 case Sema::VAK_Undefined:
3730 case Sema::VAK_MSVCUndefined:
3731 EmitFormatDiagnostic(
3732 S.PDiag(diag::warn_non_pod_vararg_with_format_string)
3733 << S.getLangOpts().CPlusPlus11
3736 << AT.getRepresentativeTypeName(S.Context)
3738 << E->getSourceRange(),
3739 E->getLocStart(), /*IsStringLocation*/false, CSR);
3740 checkForCStrMembers(AT, E);
3743 case Sema::VAK_Invalid:
3744 if (ExprTy->isObjCObjectType())
3745 EmitFormatDiagnostic(
3746 S.PDiag(diag::err_cannot_pass_objc_interface_to_vararg_format)
3747 << S.getLangOpts().CPlusPlus11
3750 << AT.getRepresentativeTypeName(S.Context)
3752 << E->getSourceRange(),
3753 E->getLocStart(), /*IsStringLocation*/false, CSR);
3755 // FIXME: If this is an initializer list, suggest removing the braces
3756 // or inserting a cast to the target type.
3757 S.Diag(E->getLocStart(), diag::err_cannot_pass_to_vararg_format)
3758 << isa<InitListExpr>(E) << ExprTy << CallType
3759 << AT.getRepresentativeTypeName(S.Context)
3760 << E->getSourceRange();
3764 assert(FirstDataArg + FS.getArgIndex() < CheckedVarArgs.size() &&
3765 "format string specifier index out of range");
3766 CheckedVarArgs[FirstDataArg + FS.getArgIndex()] = true;
3772 //===--- CHECK: Scanf format string checking ------------------------------===//
3775 class CheckScanfHandler : public CheckFormatHandler {
3777 CheckScanfHandler(Sema &s, const StringLiteral *fexpr,
3778 const Expr *origFormatExpr, unsigned firstDataArg,
3779 unsigned numDataArgs, const char *beg, bool hasVAListArg,
3780 ArrayRef<const Expr *> Args,
3781 unsigned formatIdx, bool inFunctionCall,
3782 Sema::VariadicCallType CallType,
3783 llvm::SmallBitVector &CheckedVarArgs)
3784 : CheckFormatHandler(s, fexpr, origFormatExpr, firstDataArg,
3785 numDataArgs, beg, hasVAListArg,
3786 Args, formatIdx, inFunctionCall, CallType,
3790 bool HandleScanfSpecifier(const analyze_scanf::ScanfSpecifier &FS,
3791 const char *startSpecifier,
3792 unsigned specifierLen) override;
3794 bool HandleInvalidScanfConversionSpecifier(
3795 const analyze_scanf::ScanfSpecifier &FS,
3796 const char *startSpecifier,
3797 unsigned specifierLen) override;
3799 void HandleIncompleteScanList(const char *start, const char *end) override;
3803 void CheckScanfHandler::HandleIncompleteScanList(const char *start,
3805 EmitFormatDiagnostic(S.PDiag(diag::warn_scanf_scanlist_incomplete),
3806 getLocationOfByte(end), /*IsStringLocation*/true,
3807 getSpecifierRange(start, end - start));
3810 bool CheckScanfHandler::HandleInvalidScanfConversionSpecifier(
3811 const analyze_scanf::ScanfSpecifier &FS,
3812 const char *startSpecifier,
3813 unsigned specifierLen) {
3815 const analyze_scanf::ScanfConversionSpecifier &CS =
3816 FS.getConversionSpecifier();
3818 return HandleInvalidConversionSpecifier(FS.getArgIndex(),
3819 getLocationOfByte(CS.getStart()),
3820 startSpecifier, specifierLen,
3821 CS.getStart(), CS.getLength());
3824 bool CheckScanfHandler::HandleScanfSpecifier(
3825 const analyze_scanf::ScanfSpecifier &FS,
3826 const char *startSpecifier,
3827 unsigned specifierLen) {
3829 using namespace analyze_scanf;
3830 using namespace analyze_format_string;
3832 const ScanfConversionSpecifier &CS = FS.getConversionSpecifier();
3834 // Handle case where '%' and '*' don't consume an argument. These shouldn't
3835 // be used to decide if we are using positional arguments consistently.
3836 if (FS.consumesDataArgument()) {
3839 usesPositionalArgs = FS.usesPositionalArg();
3841 else if (usesPositionalArgs != FS.usesPositionalArg()) {
3842 HandlePositionalNonpositionalArgs(getLocationOfByte(CS.getStart()),
3843 startSpecifier, specifierLen);
3848 // Check if the field with is non-zero.
3849 const OptionalAmount &Amt = FS.getFieldWidth();
3850 if (Amt.getHowSpecified() == OptionalAmount::Constant) {
3851 if (Amt.getConstantAmount() == 0) {
3852 const CharSourceRange &R = getSpecifierRange(Amt.getStart(),
3853 Amt.getConstantLength());
3854 EmitFormatDiagnostic(S.PDiag(diag::warn_scanf_nonzero_width),
3855 getLocationOfByte(Amt.getStart()),
3856 /*IsStringLocation*/true, R,
3857 FixItHint::CreateRemoval(R));
3861 if (!FS.consumesDataArgument()) {
3862 // FIXME: Technically specifying a precision or field width here
3863 // makes no sense. Worth issuing a warning at some point.
3867 // Consume the argument.
3868 unsigned argIndex = FS.getArgIndex();
3869 if (argIndex < NumDataArgs) {
3870 // The check to see if the argIndex is valid will come later.
3871 // We set the bit here because we may exit early from this
3872 // function if we encounter some other error.
3873 CoveredArgs.set(argIndex);
3876 // Check the length modifier is valid with the given conversion specifier.
3877 if (!FS.hasValidLengthModifier(S.getASTContext().getTargetInfo()))
3878 HandleInvalidLengthModifier(FS, CS, startSpecifier, specifierLen,
3879 diag::warn_format_nonsensical_length);
3880 else if (!FS.hasStandardLengthModifier())
3881 HandleNonStandardLengthModifier(FS, startSpecifier, specifierLen);
3882 else if (!FS.hasStandardLengthConversionCombination())
3883 HandleInvalidLengthModifier(FS, CS, startSpecifier, specifierLen,
3884 diag::warn_format_non_standard_conversion_spec);
3886 if (!FS.hasStandardConversionSpecifier(S.getLangOpts()))
3887 HandleNonStandardConversionSpecifier(CS, startSpecifier, specifierLen);
3889 // The remaining checks depend on the data arguments.
3893 if (!CheckNumArgs(FS, CS, startSpecifier, specifierLen, argIndex))
3896 // Check that the argument type matches the format specifier.
3897 const Expr *Ex = getDataArg(argIndex);
3901 const analyze_format_string::ArgType &AT = FS.getArgType(S.Context);
3902 if (AT.isValid() && !AT.matchesType(S.Context, Ex->getType())) {
3903 ScanfSpecifier fixedFS = FS;
3904 bool success = fixedFS.fixType(Ex->getType(),
3905 Ex->IgnoreImpCasts()->getType(),
3906 S.getLangOpts(), S.Context);
3909 // Get the fix string from the fixed format specifier.
3910 SmallString<128> buf;
3911 llvm::raw_svector_ostream os(buf);
3912 fixedFS.toString(os);
3914 EmitFormatDiagnostic(
3915 S.PDiag(diag::warn_format_conversion_argument_type_mismatch)
3916 << AT.getRepresentativeTypeName(S.Context) << Ex->getType() << false
3917 << Ex->getSourceRange(),
3919 /*IsStringLocation*/false,
3920 getSpecifierRange(startSpecifier, specifierLen),
3921 FixItHint::CreateReplacement(
3922 getSpecifierRange(startSpecifier, specifierLen),
3925 EmitFormatDiagnostic(
3926 S.PDiag(diag::warn_format_conversion_argument_type_mismatch)
3927 << AT.getRepresentativeTypeName(S.Context) << Ex->getType() << false
3928 << Ex->getSourceRange(),
3930 /*IsStringLocation*/false,
3931 getSpecifierRange(startSpecifier, specifierLen));
3938 void Sema::CheckFormatString(const StringLiteral *FExpr,
3939 const Expr *OrigFormatExpr,
3940 ArrayRef<const Expr *> Args,
3941 bool HasVAListArg, unsigned format_idx,
3942 unsigned firstDataArg, FormatStringType Type,
3943 bool inFunctionCall, VariadicCallType CallType,
3944 llvm::SmallBitVector &CheckedVarArgs) {
3946 // CHECK: is the format string a wide literal?
3947 if (!FExpr->isAscii() && !FExpr->isUTF8()) {
3948 CheckFormatHandler::EmitFormatDiagnostic(
3949 *this, inFunctionCall, Args[format_idx],
3950 PDiag(diag::warn_format_string_is_wide_literal), FExpr->getLocStart(),
3951 /*IsStringLocation*/true, OrigFormatExpr->getSourceRange());
3955 // Str - The format string. NOTE: this is NOT null-terminated!
3956 StringRef StrRef = FExpr->getString();
3957 const char *Str = StrRef.data();
3958 // Account for cases where the string literal is truncated in a declaration.
3959 const ConstantArrayType *T = Context.getAsConstantArrayType(FExpr->getType());
3960 assert(T && "String literal not of constant array type!");
3961 size_t TypeSize = T->getSize().getZExtValue();
3962 size_t StrLen = std::min(std::max(TypeSize, size_t(1)) - 1, StrRef.size());
3963 const unsigned numDataArgs = Args.size() - firstDataArg;
3965 // Emit a warning if the string literal is truncated and does not contain an
3966 // embedded null character.
3967 if (TypeSize <= StrRef.size() &&
3968 StrRef.substr(0, TypeSize).find('\0') == StringRef::npos) {
3969 CheckFormatHandler::EmitFormatDiagnostic(
3970 *this, inFunctionCall, Args[format_idx],
3971 PDiag(diag::warn_printf_format_string_not_null_terminated),
3972 FExpr->getLocStart(),
3973 /*IsStringLocation=*/true, OrigFormatExpr->getSourceRange());
3977 // CHECK: empty format string?
3978 if (StrLen == 0 && numDataArgs > 0) {
3979 CheckFormatHandler::EmitFormatDiagnostic(
3980 *this, inFunctionCall, Args[format_idx],
3981 PDiag(diag::warn_empty_format_string), FExpr->getLocStart(),
3982 /*IsStringLocation*/true, OrigFormatExpr->getSourceRange());
3986 if (Type == FST_Printf || Type == FST_NSString) {
3987 CheckPrintfHandler H(*this, FExpr, OrigFormatExpr, firstDataArg,
3988 numDataArgs, (Type == FST_NSString),
3989 Str, HasVAListArg, Args, format_idx,
3990 inFunctionCall, CallType, CheckedVarArgs);
3992 if (!analyze_format_string::ParsePrintfString(H, Str, Str + StrLen,
3994 Context.getTargetInfo()))
3996 } else if (Type == FST_Scanf) {
3997 CheckScanfHandler H(*this, FExpr, OrigFormatExpr, firstDataArg, numDataArgs,
3998 Str, HasVAListArg, Args, format_idx,
3999 inFunctionCall, CallType, CheckedVarArgs);
4001 if (!analyze_format_string::ParseScanfString(H, Str, Str + StrLen,
4003 Context.getTargetInfo()))
4005 } // TODO: handle other formats
4008 bool Sema::FormatStringHasSArg(const StringLiteral *FExpr) {
4009 // Str - The format string. NOTE: this is NOT null-terminated!
4010 StringRef StrRef = FExpr->getString();
4011 const char *Str = StrRef.data();
4012 // Account for cases where the string literal is truncated in a declaration.
4013 const ConstantArrayType *T = Context.getAsConstantArrayType(FExpr->getType());
4014 assert(T && "String literal not of constant array type!");
4015 size_t TypeSize = T->getSize().getZExtValue();
4016 size_t StrLen = std::min(std::max(TypeSize, size_t(1)) - 1, StrRef.size());
4017 return analyze_format_string::ParseFormatStringHasSArg(Str, Str + StrLen,
4019 Context.getTargetInfo());
4022 //===--- CHECK: Warn on use of wrong absolute value function. -------------===//
4024 // Returns the related absolute value function that is larger, of 0 if one
4026 static unsigned getLargerAbsoluteValueFunction(unsigned AbsFunction) {
4027 switch (AbsFunction) {
4031 case Builtin::BI__builtin_abs:
4032 return Builtin::BI__builtin_labs;
4033 case Builtin::BI__builtin_labs:
4034 return Builtin::BI__builtin_llabs;
4035 case Builtin::BI__builtin_llabs:
4038 case Builtin::BI__builtin_fabsf:
4039 return Builtin::BI__builtin_fabs;
4040 case Builtin::BI__builtin_fabs:
4041 return Builtin::BI__builtin_fabsl;
4042 case Builtin::BI__builtin_fabsl:
4045 case Builtin::BI__builtin_cabsf:
4046 return Builtin::BI__builtin_cabs;
4047 case Builtin::BI__builtin_cabs:
4048 return Builtin::BI__builtin_cabsl;
4049 case Builtin::BI__builtin_cabsl:
4052 case Builtin::BIabs:
4053 return Builtin::BIlabs;
4054 case Builtin::BIlabs:
4055 return Builtin::BIllabs;
4056 case Builtin::BIllabs:
4059 case Builtin::BIfabsf:
4060 return Builtin::BIfabs;
4061 case Builtin::BIfabs:
4062 return Builtin::BIfabsl;
4063 case Builtin::BIfabsl:
4066 case Builtin::BIcabsf:
4067 return Builtin::BIcabs;
4068 case Builtin::BIcabs:
4069 return Builtin::BIcabsl;
4070 case Builtin::BIcabsl:
4075 // Returns the argument type of the absolute value function.
4076 static QualType getAbsoluteValueArgumentType(ASTContext &Context,
4081 ASTContext::GetBuiltinTypeError Error = ASTContext::GE_None;
4082 QualType BuiltinType = Context.GetBuiltinType(AbsType, Error);
4083 if (Error != ASTContext::GE_None)
4086 const FunctionProtoType *FT = BuiltinType->getAs<FunctionProtoType>();
4090 if (FT->getNumParams() != 1)
4093 return FT->getParamType(0);
4096 // Returns the best absolute value function, or zero, based on type and
4097 // current absolute value function.
4098 static unsigned getBestAbsFunction(ASTContext &Context, QualType ArgType,
4099 unsigned AbsFunctionKind) {
4100 unsigned BestKind = 0;
4101 uint64_t ArgSize = Context.getTypeSize(ArgType);
4102 for (unsigned Kind = AbsFunctionKind; Kind != 0;
4103 Kind = getLargerAbsoluteValueFunction(Kind)) {
4104 QualType ParamType = getAbsoluteValueArgumentType(Context, Kind);
4105 if (Context.getTypeSize(ParamType) >= ArgSize) {
4108 else if (Context.hasSameType(ParamType, ArgType)) {
4117 enum AbsoluteValueKind {
4123 static AbsoluteValueKind getAbsoluteValueKind(QualType T) {
4124 if (T->isIntegralOrEnumerationType())
4126 if (T->isRealFloatingType())
4127 return AVK_Floating;
4128 if (T->isAnyComplexType())
4131 llvm_unreachable("Type not integer, floating, or complex");
4134 // Changes the absolute value function to a different type. Preserves whether
4135 // the function is a builtin.
4136 static unsigned changeAbsFunction(unsigned AbsKind,
4137 AbsoluteValueKind ValueKind) {
4138 switch (ValueKind) {
4143 case Builtin::BI__builtin_fabsf:
4144 case Builtin::BI__builtin_fabs:
4145 case Builtin::BI__builtin_fabsl:
4146 case Builtin::BI__builtin_cabsf:
4147 case Builtin::BI__builtin_cabs:
4148 case Builtin::BI__builtin_cabsl:
4149 return Builtin::BI__builtin_abs;
4150 case Builtin::BIfabsf:
4151 case Builtin::BIfabs:
4152 case Builtin::BIfabsl:
4153 case Builtin::BIcabsf:
4154 case Builtin::BIcabs:
4155 case Builtin::BIcabsl:
4156 return Builtin::BIabs;
4162 case Builtin::BI__builtin_abs:
4163 case Builtin::BI__builtin_labs:
4164 case Builtin::BI__builtin_llabs:
4165 case Builtin::BI__builtin_cabsf:
4166 case Builtin::BI__builtin_cabs:
4167 case Builtin::BI__builtin_cabsl:
4168 return Builtin::BI__builtin_fabsf;
4169 case Builtin::BIabs:
4170 case Builtin::BIlabs:
4171 case Builtin::BIllabs:
4172 case Builtin::BIcabsf:
4173 case Builtin::BIcabs:
4174 case Builtin::BIcabsl:
4175 return Builtin::BIfabsf;
4181 case Builtin::BI__builtin_abs:
4182 case Builtin::BI__builtin_labs:
4183 case Builtin::BI__builtin_llabs:
4184 case Builtin::BI__builtin_fabsf:
4185 case Builtin::BI__builtin_fabs:
4186 case Builtin::BI__builtin_fabsl:
4187 return Builtin::BI__builtin_cabsf;
4188 case Builtin::BIabs:
4189 case Builtin::BIlabs:
4190 case Builtin::BIllabs:
4191 case Builtin::BIfabsf:
4192 case Builtin::BIfabs:
4193 case Builtin::BIfabsl:
4194 return Builtin::BIcabsf;
4197 llvm_unreachable("Unable to convert function");
4200 static unsigned getAbsoluteValueFunctionKind(const FunctionDecl *FDecl) {
4201 const IdentifierInfo *FnInfo = FDecl->getIdentifier();
4205 switch (FDecl->getBuiltinID()) {
4208 case Builtin::BI__builtin_abs:
4209 case Builtin::BI__builtin_fabs:
4210 case Builtin::BI__builtin_fabsf:
4211 case Builtin::BI__builtin_fabsl:
4212 case Builtin::BI__builtin_labs:
4213 case Builtin::BI__builtin_llabs:
4214 case Builtin::BI__builtin_cabs:
4215 case Builtin::BI__builtin_cabsf:
4216 case Builtin::BI__builtin_cabsl:
4217 case Builtin::BIabs:
4218 case Builtin::BIlabs:
4219 case Builtin::BIllabs:
4220 case Builtin::BIfabs:
4221 case Builtin::BIfabsf:
4222 case Builtin::BIfabsl:
4223 case Builtin::BIcabs:
4224 case Builtin::BIcabsf:
4225 case Builtin::BIcabsl:
4226 return FDecl->getBuiltinID();
4228 llvm_unreachable("Unknown Builtin type");
4231 // If the replacement is valid, emit a note with replacement function.
4232 // Additionally, suggest including the proper header if not already included.
4233 static void emitReplacement(Sema &S, SourceLocation Loc, SourceRange Range,
4234 unsigned AbsKind, QualType ArgType) {
4235 bool EmitHeaderHint = true;
4236 const char *HeaderName = nullptr;
4237 const char *FunctionName = nullptr;
4238 if (S.getLangOpts().CPlusPlus && !ArgType->isAnyComplexType()) {
4239 FunctionName = "std::abs";
4240 if (ArgType->isIntegralOrEnumerationType()) {
4241 HeaderName = "cstdlib";
4242 } else if (ArgType->isRealFloatingType()) {
4243 HeaderName = "cmath";
4245 llvm_unreachable("Invalid Type");
4248 // Lookup all std::abs
4249 if (NamespaceDecl *Std = S.getStdNamespace()) {
4250 LookupResult R(S, &S.Context.Idents.get("abs"), Loc, Sema::LookupAnyName);
4251 R.suppressDiagnostics();
4252 S.LookupQualifiedName(R, Std);
4254 for (const auto *I : R) {
4255 const FunctionDecl *FDecl = nullptr;
4256 if (const UsingShadowDecl *UsingD = dyn_cast<UsingShadowDecl>(I)) {
4257 FDecl = dyn_cast<FunctionDecl>(UsingD->getTargetDecl());
4259 FDecl = dyn_cast<FunctionDecl>(I);
4264 // Found std::abs(), check that they are the right ones.
4265 if (FDecl->getNumParams() != 1)
4268 // Check that the parameter type can handle the argument.
4269 QualType ParamType = FDecl->getParamDecl(0)->getType();
4270 if (getAbsoluteValueKind(ArgType) == getAbsoluteValueKind(ParamType) &&
4271 S.Context.getTypeSize(ArgType) <=
4272 S.Context.getTypeSize(ParamType)) {
4273 // Found a function, don't need the header hint.
4274 EmitHeaderHint = false;
4280 FunctionName = S.Context.BuiltinInfo.GetName(AbsKind);
4281 HeaderName = S.Context.BuiltinInfo.getHeaderName(AbsKind);
4284 DeclarationName DN(&S.Context.Idents.get(FunctionName));
4285 LookupResult R(S, DN, Loc, Sema::LookupAnyName);
4286 R.suppressDiagnostics();
4287 S.LookupName(R, S.getCurScope());
4289 if (R.isSingleResult()) {
4290 FunctionDecl *FD = dyn_cast<FunctionDecl>(R.getFoundDecl());
4291 if (FD && FD->getBuiltinID() == AbsKind) {
4292 EmitHeaderHint = false;
4296 } else if (!R.empty()) {
4302 S.Diag(Loc, diag::note_replace_abs_function)
4303 << FunctionName << FixItHint::CreateReplacement(Range, FunctionName);
4308 if (!EmitHeaderHint)
4311 S.Diag(Loc, diag::note_include_header_or_declare) << HeaderName
4315 static bool IsFunctionStdAbs(const FunctionDecl *FDecl) {
4319 if (!FDecl->getIdentifier() || !FDecl->getIdentifier()->isStr("abs"))
4322 const NamespaceDecl *ND = dyn_cast<NamespaceDecl>(FDecl->getDeclContext());
4324 while (ND && ND->isInlineNamespace()) {
4325 ND = dyn_cast<NamespaceDecl>(ND->getDeclContext());
4328 if (!ND || !ND->getIdentifier() || !ND->getIdentifier()->isStr("std"))
4331 if (!isa<TranslationUnitDecl>(ND->getDeclContext()))
4337 // Warn when using the wrong abs() function.
4338 void Sema::CheckAbsoluteValueFunction(const CallExpr *Call,
4339 const FunctionDecl *FDecl,
4340 IdentifierInfo *FnInfo) {
4341 if (Call->getNumArgs() != 1)
4344 unsigned AbsKind = getAbsoluteValueFunctionKind(FDecl);
4345 bool IsStdAbs = IsFunctionStdAbs(FDecl);
4346 if (AbsKind == 0 && !IsStdAbs)
4349 QualType ArgType = Call->getArg(0)->IgnoreParenImpCasts()->getType();
4350 QualType ParamType = Call->getArg(0)->getType();
4352 // Unsigned types cannot be negative. Suggest removing the absolute value
4354 if (ArgType->isUnsignedIntegerType()) {
4355 const char *FunctionName =
4356 IsStdAbs ? "std::abs" : Context.BuiltinInfo.GetName(AbsKind);
4357 Diag(Call->getExprLoc(), diag::warn_unsigned_abs) << ArgType << ParamType;
4358 Diag(Call->getExprLoc(), diag::note_remove_abs)
4360 << FixItHint::CreateRemoval(Call->getCallee()->getSourceRange());
4364 // std::abs has overloads which prevent most of the absolute value problems
4369 AbsoluteValueKind ArgValueKind = getAbsoluteValueKind(ArgType);
4370 AbsoluteValueKind ParamValueKind = getAbsoluteValueKind(ParamType);
4372 // The argument and parameter are the same kind. Check if they are the right
4374 if (ArgValueKind == ParamValueKind) {
4375 if (Context.getTypeSize(ArgType) <= Context.getTypeSize(ParamType))
4378 unsigned NewAbsKind = getBestAbsFunction(Context, ArgType, AbsKind);
4379 Diag(Call->getExprLoc(), diag::warn_abs_too_small)
4380 << FDecl << ArgType << ParamType;
4382 if (NewAbsKind == 0)
4385 emitReplacement(*this, Call->getExprLoc(),
4386 Call->getCallee()->getSourceRange(), NewAbsKind, ArgType);
4390 // ArgValueKind != ParamValueKind
4391 // The wrong type of absolute value function was used. Attempt to find the
4393 unsigned NewAbsKind = changeAbsFunction(AbsKind, ArgValueKind);
4394 NewAbsKind = getBestAbsFunction(Context, ArgType, NewAbsKind);
4395 if (NewAbsKind == 0)
4398 Diag(Call->getExprLoc(), diag::warn_wrong_absolute_value_type)
4399 << FDecl << ParamValueKind << ArgValueKind;
4401 emitReplacement(*this, Call->getExprLoc(),
4402 Call->getCallee()->getSourceRange(), NewAbsKind, ArgType);
4406 //===--- CHECK: Standard memory functions ---------------------------------===//
4408 /// \brief Takes the expression passed to the size_t parameter of functions
4409 /// such as memcmp, strncat, etc and warns if it's a comparison.
4411 /// This is to catch typos like `if (memcmp(&a, &b, sizeof(a) > 0))`.
4412 static bool CheckMemorySizeofForComparison(Sema &S, const Expr *E,
4413 IdentifierInfo *FnName,
4414 SourceLocation FnLoc,
4415 SourceLocation RParenLoc) {
4416 const BinaryOperator *Size = dyn_cast<BinaryOperator>(E);
4420 // if E is binop and op is >, <, >=, <=, ==, &&, ||:
4421 if (!Size->isComparisonOp() && !Size->isEqualityOp() && !Size->isLogicalOp())
4424 SourceRange SizeRange = Size->getSourceRange();
4425 S.Diag(Size->getOperatorLoc(), diag::warn_memsize_comparison)
4426 << SizeRange << FnName;
4427 S.Diag(FnLoc, diag::note_memsize_comparison_paren)
4428 << FnName << FixItHint::CreateInsertion(
4429 S.getLocForEndOfToken(Size->getLHS()->getLocEnd()), ")")
4430 << FixItHint::CreateRemoval(RParenLoc);
4431 S.Diag(SizeRange.getBegin(), diag::note_memsize_comparison_cast_silence)
4432 << FixItHint::CreateInsertion(SizeRange.getBegin(), "(size_t)(")
4433 << FixItHint::CreateInsertion(S.getLocForEndOfToken(SizeRange.getEnd()),
4439 /// \brief Determine whether the given type is or contains a dynamic class type
4440 /// (e.g., whether it has a vtable).
4441 static const CXXRecordDecl *getContainedDynamicClass(QualType T,
4442 bool &IsContained) {
4443 // Look through array types while ignoring qualifiers.
4444 const Type *Ty = T->getBaseElementTypeUnsafe();
4445 IsContained = false;
4447 const CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
4448 RD = RD ? RD->getDefinition() : nullptr;
4452 if (RD->isDynamicClass())
4455 // Check all the fields. If any bases were dynamic, the class is dynamic.
4456 // It's impossible for a class to transitively contain itself by value, so
4457 // infinite recursion is impossible.
4458 for (auto *FD : RD->fields()) {
4460 if (const CXXRecordDecl *ContainedRD =
4461 getContainedDynamicClass(FD->getType(), SubContained)) {
4470 /// \brief If E is a sizeof expression, returns its argument expression,
4471 /// otherwise returns NULL.
4472 static const Expr *getSizeOfExprArg(const Expr* E) {
4473 if (const UnaryExprOrTypeTraitExpr *SizeOf =
4474 dyn_cast<UnaryExprOrTypeTraitExpr>(E))
4475 if (SizeOf->getKind() == clang::UETT_SizeOf && !SizeOf->isArgumentType())
4476 return SizeOf->getArgumentExpr()->IgnoreParenImpCasts();
4481 /// \brief If E is a sizeof expression, returns its argument type.
4482 static QualType getSizeOfArgType(const Expr* E) {
4483 if (const UnaryExprOrTypeTraitExpr *SizeOf =
4484 dyn_cast<UnaryExprOrTypeTraitExpr>(E))
4485 if (SizeOf->getKind() == clang::UETT_SizeOf)
4486 return SizeOf->getTypeOfArgument();
4491 /// \brief Check for dangerous or invalid arguments to memset().
4493 /// This issues warnings on known problematic, dangerous or unspecified
4494 /// arguments to the standard 'memset', 'memcpy', 'memmove', and 'memcmp'
4497 /// \param Call The call expression to diagnose.
4498 void Sema::CheckMemaccessArguments(const CallExpr *Call,
4500 IdentifierInfo *FnName) {
4503 // It is possible to have a non-standard definition of memset. Validate
4504 // we have enough arguments, and if not, abort further checking.
4505 unsigned ExpectedNumArgs = (BId == Builtin::BIstrndup ? 2 : 3);
4506 if (Call->getNumArgs() < ExpectedNumArgs)
4509 unsigned LastArg = (BId == Builtin::BImemset ||
4510 BId == Builtin::BIstrndup ? 1 : 2);
4511 unsigned LenArg = (BId == Builtin::BIstrndup ? 1 : 2);
4512 const Expr *LenExpr = Call->getArg(LenArg)->IgnoreParenImpCasts();
4514 if (CheckMemorySizeofForComparison(*this, LenExpr, FnName,
4515 Call->getLocStart(), Call->getRParenLoc()))
4518 // We have special checking when the length is a sizeof expression.
4519 QualType SizeOfArgTy = getSizeOfArgType(LenExpr);
4520 const Expr *SizeOfArg = getSizeOfExprArg(LenExpr);
4521 llvm::FoldingSetNodeID SizeOfArgID;
4523 for (unsigned ArgIdx = 0; ArgIdx != LastArg; ++ArgIdx) {
4524 const Expr *Dest = Call->getArg(ArgIdx)->IgnoreParenImpCasts();
4525 SourceRange ArgRange = Call->getArg(ArgIdx)->getSourceRange();
4527 QualType DestTy = Dest->getType();
4528 if (const PointerType *DestPtrTy = DestTy->getAs<PointerType>()) {
4529 QualType PointeeTy = DestPtrTy->getPointeeType();
4531 // Never warn about void type pointers. This can be used to suppress
4533 if (PointeeTy->isVoidType())
4536 // Catch "memset(p, 0, sizeof(p))" -- needs to be sizeof(*p). Do this by
4537 // actually comparing the expressions for equality. Because computing the
4538 // expression IDs can be expensive, we only do this if the diagnostic is
4541 !Diags.isIgnored(diag::warn_sizeof_pointer_expr_memaccess,
4542 SizeOfArg->getExprLoc())) {
4543 // We only compute IDs for expressions if the warning is enabled, and
4544 // cache the sizeof arg's ID.
4545 if (SizeOfArgID == llvm::FoldingSetNodeID())
4546 SizeOfArg->Profile(SizeOfArgID, Context, true);
4547 llvm::FoldingSetNodeID DestID;
4548 Dest->Profile(DestID, Context, true);
4549 if (DestID == SizeOfArgID) {
4550 // TODO: For strncpy() and friends, this could suggest sizeof(dst)
4551 // over sizeof(src) as well.
4552 unsigned ActionIdx = 0; // Default is to suggest dereferencing.
4553 StringRef ReadableName = FnName->getName();
4555 if (const UnaryOperator *UnaryOp = dyn_cast<UnaryOperator>(Dest))
4556 if (UnaryOp->getOpcode() == UO_AddrOf)
4557 ActionIdx = 1; // If its an address-of operator, just remove it.
4558 if (!PointeeTy->isIncompleteType() &&
4559 (Context.getTypeSize(PointeeTy) == Context.getCharWidth()))
4560 ActionIdx = 2; // If the pointee's size is sizeof(char),
4561 // suggest an explicit length.
4563 // If the function is defined as a builtin macro, do not show macro
4565 SourceLocation SL = SizeOfArg->getExprLoc();
4566 SourceRange DSR = Dest->getSourceRange();
4567 SourceRange SSR = SizeOfArg->getSourceRange();
4568 SourceManager &SM = getSourceManager();
4570 if (SM.isMacroArgExpansion(SL)) {
4571 ReadableName = Lexer::getImmediateMacroName(SL, SM, LangOpts);
4572 SL = SM.getSpellingLoc(SL);
4573 DSR = SourceRange(SM.getSpellingLoc(DSR.getBegin()),
4574 SM.getSpellingLoc(DSR.getEnd()));
4575 SSR = SourceRange(SM.getSpellingLoc(SSR.getBegin()),
4576 SM.getSpellingLoc(SSR.getEnd()));
4579 DiagRuntimeBehavior(SL, SizeOfArg,
4580 PDiag(diag::warn_sizeof_pointer_expr_memaccess)
4586 DiagRuntimeBehavior(SL, SizeOfArg,
4587 PDiag(diag::warn_sizeof_pointer_expr_memaccess_note)
4595 // Also check for cases where the sizeof argument is the exact same
4596 // type as the memory argument, and where it points to a user-defined
4598 if (SizeOfArgTy != QualType()) {
4599 if (PointeeTy->isRecordType() &&
4600 Context.typesAreCompatible(SizeOfArgTy, DestTy)) {
4601 DiagRuntimeBehavior(LenExpr->getExprLoc(), Dest,
4602 PDiag(diag::warn_sizeof_pointer_type_memaccess)
4603 << FnName << SizeOfArgTy << ArgIdx
4604 << PointeeTy << Dest->getSourceRange()
4605 << LenExpr->getSourceRange());
4610 // Always complain about dynamic classes.
4612 if (const CXXRecordDecl *ContainedRD =
4613 getContainedDynamicClass(PointeeTy, IsContained)) {
4615 unsigned OperationType = 0;
4616 // "overwritten" if we're warning about the destination for any call
4617 // but memcmp; otherwise a verb appropriate to the call.
4618 if (ArgIdx != 0 || BId == Builtin::BImemcmp) {
4619 if (BId == Builtin::BImemcpy)
4621 else if(BId == Builtin::BImemmove)
4623 else if (BId == Builtin::BImemcmp)
4627 DiagRuntimeBehavior(
4628 Dest->getExprLoc(), Dest,
4629 PDiag(diag::warn_dyn_class_memaccess)
4630 << (BId == Builtin::BImemcmp ? ArgIdx + 2 : ArgIdx)
4631 << FnName << IsContained << ContainedRD << OperationType
4632 << Call->getCallee()->getSourceRange());
4633 } else if (PointeeTy.hasNonTrivialObjCLifetime() &&
4634 BId != Builtin::BImemset)
4635 DiagRuntimeBehavior(
4636 Dest->getExprLoc(), Dest,
4637 PDiag(diag::warn_arc_object_memaccess)
4638 << ArgIdx << FnName << PointeeTy
4639 << Call->getCallee()->getSourceRange());
4643 DiagRuntimeBehavior(
4644 Dest->getExprLoc(), Dest,
4645 PDiag(diag::note_bad_memaccess_silence)
4646 << FixItHint::CreateInsertion(ArgRange.getBegin(), "(void*)"));
4652 // A little helper routine: ignore addition and subtraction of integer literals.
4653 // This intentionally does not ignore all integer constant expressions because
4654 // we don't want to remove sizeof().
4655 static const Expr *ignoreLiteralAdditions(const Expr *Ex, ASTContext &Ctx) {
4656 Ex = Ex->IgnoreParenCasts();
4659 const BinaryOperator * BO = dyn_cast<BinaryOperator>(Ex);
4660 if (!BO || !BO->isAdditiveOp())
4663 const Expr *RHS = BO->getRHS()->IgnoreParenCasts();
4664 const Expr *LHS = BO->getLHS()->IgnoreParenCasts();
4666 if (isa<IntegerLiteral>(RHS))
4668 else if (isa<IntegerLiteral>(LHS))
4677 static bool isConstantSizeArrayWithMoreThanOneElement(QualType Ty,
4678 ASTContext &Context) {
4679 // Only handle constant-sized or VLAs, but not flexible members.
4680 if (const ConstantArrayType *CAT = Context.getAsConstantArrayType(Ty)) {
4681 // Only issue the FIXIT for arrays of size > 1.
4682 if (CAT->getSize().getSExtValue() <= 1)
4684 } else if (!Ty->isVariableArrayType()) {
4690 // Warn if the user has made the 'size' argument to strlcpy or strlcat
4691 // be the size of the source, instead of the destination.
4692 void Sema::CheckStrlcpycatArguments(const CallExpr *Call,
4693 IdentifierInfo *FnName) {
4695 // Don't crash if the user has the wrong number of arguments
4696 unsigned NumArgs = Call->getNumArgs();
4697 if ((NumArgs != 3) && (NumArgs != 4))
4700 const Expr *SrcArg = ignoreLiteralAdditions(Call->getArg(1), Context);
4701 const Expr *SizeArg = ignoreLiteralAdditions(Call->getArg(2), Context);
4702 const Expr *CompareWithSrc = nullptr;
4704 if (CheckMemorySizeofForComparison(*this, SizeArg, FnName,
4705 Call->getLocStart(), Call->getRParenLoc()))
4708 // Look for 'strlcpy(dst, x, sizeof(x))'
4709 if (const Expr *Ex = getSizeOfExprArg(SizeArg))
4710 CompareWithSrc = Ex;
4712 // Look for 'strlcpy(dst, x, strlen(x))'
4713 if (const CallExpr *SizeCall = dyn_cast<CallExpr>(SizeArg)) {
4714 if (SizeCall->getBuiltinCallee() == Builtin::BIstrlen &&
4715 SizeCall->getNumArgs() == 1)
4716 CompareWithSrc = ignoreLiteralAdditions(SizeCall->getArg(0), Context);
4720 if (!CompareWithSrc)
4723 // Determine if the argument to sizeof/strlen is equal to the source
4724 // argument. In principle there's all kinds of things you could do
4725 // here, for instance creating an == expression and evaluating it with
4726 // EvaluateAsBooleanCondition, but this uses a more direct technique:
4727 const DeclRefExpr *SrcArgDRE = dyn_cast<DeclRefExpr>(SrcArg);
4731 const DeclRefExpr *CompareWithSrcDRE = dyn_cast<DeclRefExpr>(CompareWithSrc);
4732 if (!CompareWithSrcDRE ||
4733 SrcArgDRE->getDecl() != CompareWithSrcDRE->getDecl())
4736 const Expr *OriginalSizeArg = Call->getArg(2);
4737 Diag(CompareWithSrcDRE->getLocStart(), diag::warn_strlcpycat_wrong_size)
4738 << OriginalSizeArg->getSourceRange() << FnName;
4740 // Output a FIXIT hint if the destination is an array (rather than a
4741 // pointer to an array). This could be enhanced to handle some
4742 // pointers if we know the actual size, like if DstArg is 'array+2'
4743 // we could say 'sizeof(array)-2'.
4744 const Expr *DstArg = Call->getArg(0)->IgnoreParenImpCasts();
4745 if (!isConstantSizeArrayWithMoreThanOneElement(DstArg->getType(), Context))
4748 SmallString<128> sizeString;
4749 llvm::raw_svector_ostream OS(sizeString);
4751 DstArg->printPretty(OS, nullptr, getPrintingPolicy());
4754 Diag(OriginalSizeArg->getLocStart(), diag::note_strlcpycat_wrong_size)
4755 << FixItHint::CreateReplacement(OriginalSizeArg->getSourceRange(),
4759 /// Check if two expressions refer to the same declaration.
4760 static bool referToTheSameDecl(const Expr *E1, const Expr *E2) {
4761 if (const DeclRefExpr *D1 = dyn_cast_or_null<DeclRefExpr>(E1))
4762 if (const DeclRefExpr *D2 = dyn_cast_or_null<DeclRefExpr>(E2))
4763 return D1->getDecl() == D2->getDecl();
4767 static const Expr *getStrlenExprArg(const Expr *E) {
4768 if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
4769 const FunctionDecl *FD = CE->getDirectCallee();
4770 if (!FD || FD->getMemoryFunctionKind() != Builtin::BIstrlen)
4772 return CE->getArg(0)->IgnoreParenCasts();
4777 // Warn on anti-patterns as the 'size' argument to strncat.
4778 // The correct size argument should look like following:
4779 // strncat(dst, src, sizeof(dst) - strlen(dest) - 1);
4780 void Sema::CheckStrncatArguments(const CallExpr *CE,
4781 IdentifierInfo *FnName) {
4782 // Don't crash if the user has the wrong number of arguments.
4783 if (CE->getNumArgs() < 3)
4785 const Expr *DstArg = CE->getArg(0)->IgnoreParenCasts();
4786 const Expr *SrcArg = CE->getArg(1)->IgnoreParenCasts();
4787 const Expr *LenArg = CE->getArg(2)->IgnoreParenCasts();
4789 if (CheckMemorySizeofForComparison(*this, LenArg, FnName, CE->getLocStart(),
4790 CE->getRParenLoc()))
4793 // Identify common expressions, which are wrongly used as the size argument
4794 // to strncat and may lead to buffer overflows.
4795 unsigned PatternType = 0;
4796 if (const Expr *SizeOfArg = getSizeOfExprArg(LenArg)) {
4798 if (referToTheSameDecl(SizeOfArg, DstArg))
4801 else if (referToTheSameDecl(SizeOfArg, SrcArg))
4803 } else if (const BinaryOperator *BE = dyn_cast<BinaryOperator>(LenArg)) {
4804 if (BE->getOpcode() == BO_Sub) {
4805 const Expr *L = BE->getLHS()->IgnoreParenCasts();
4806 const Expr *R = BE->getRHS()->IgnoreParenCasts();
4807 // - sizeof(dst) - strlen(dst)
4808 if (referToTheSameDecl(DstArg, getSizeOfExprArg(L)) &&
4809 referToTheSameDecl(DstArg, getStrlenExprArg(R)))
4811 // - sizeof(src) - (anything)
4812 else if (referToTheSameDecl(SrcArg, getSizeOfExprArg(L)))
4817 if (PatternType == 0)
4820 // Generate the diagnostic.
4821 SourceLocation SL = LenArg->getLocStart();
4822 SourceRange SR = LenArg->getSourceRange();
4823 SourceManager &SM = getSourceManager();
4825 // If the function is defined as a builtin macro, do not show macro expansion.
4826 if (SM.isMacroArgExpansion(SL)) {
4827 SL = SM.getSpellingLoc(SL);
4828 SR = SourceRange(SM.getSpellingLoc(SR.getBegin()),
4829 SM.getSpellingLoc(SR.getEnd()));
4832 // Check if the destination is an array (rather than a pointer to an array).
4833 QualType DstTy = DstArg->getType();
4834 bool isKnownSizeArray = isConstantSizeArrayWithMoreThanOneElement(DstTy,
4836 if (!isKnownSizeArray) {
4837 if (PatternType == 1)
4838 Diag(SL, diag::warn_strncat_wrong_size) << SR;
4840 Diag(SL, diag::warn_strncat_src_size) << SR;
4844 if (PatternType == 1)
4845 Diag(SL, diag::warn_strncat_large_size) << SR;
4847 Diag(SL, diag::warn_strncat_src_size) << SR;
4849 SmallString<128> sizeString;
4850 llvm::raw_svector_ostream OS(sizeString);
4852 DstArg->printPretty(OS, nullptr, getPrintingPolicy());
4855 DstArg->printPretty(OS, nullptr, getPrintingPolicy());
4858 Diag(SL, diag::note_strncat_wrong_size)
4859 << FixItHint::CreateReplacement(SR, OS.str());
4862 //===--- CHECK: Return Address of Stack Variable --------------------------===//
4864 static Expr *EvalVal(Expr *E, SmallVectorImpl<DeclRefExpr *> &refVars,
4866 static Expr *EvalAddr(Expr* E, SmallVectorImpl<DeclRefExpr *> &refVars,
4869 /// CheckReturnStackAddr - Check if a return statement returns the address
4870 /// of a stack variable.
4872 CheckReturnStackAddr(Sema &S, Expr *RetValExp, QualType lhsType,
4873 SourceLocation ReturnLoc) {
4875 Expr *stackE = nullptr;
4876 SmallVector<DeclRefExpr *, 8> refVars;
4878 // Perform checking for returned stack addresses, local blocks,
4879 // label addresses or references to temporaries.
4880 if (lhsType->isPointerType() ||
4881 (!S.getLangOpts().ObjCAutoRefCount && lhsType->isBlockPointerType())) {
4882 stackE = EvalAddr(RetValExp, refVars, /*ParentDecl=*/nullptr);
4883 } else if (lhsType->isReferenceType()) {
4884 stackE = EvalVal(RetValExp, refVars, /*ParentDecl=*/nullptr);
4888 return; // Nothing suspicious was found.
4890 SourceLocation diagLoc;
4891 SourceRange diagRange;
4892 if (refVars.empty()) {
4893 diagLoc = stackE->getLocStart();
4894 diagRange = stackE->getSourceRange();
4896 // We followed through a reference variable. 'stackE' contains the
4897 // problematic expression but we will warn at the return statement pointing
4898 // at the reference variable. We will later display the "trail" of
4899 // reference variables using notes.
4900 diagLoc = refVars[0]->getLocStart();
4901 diagRange = refVars[0]->getSourceRange();
4904 if (DeclRefExpr *DR = dyn_cast<DeclRefExpr>(stackE)) { //address of local var.
4905 S.Diag(diagLoc, lhsType->isReferenceType() ? diag::warn_ret_stack_ref
4906 : diag::warn_ret_stack_addr)
4907 << DR->getDecl()->getDeclName() << diagRange;
4908 } else if (isa<BlockExpr>(stackE)) { // local block.
4909 S.Diag(diagLoc, diag::err_ret_local_block) << diagRange;
4910 } else if (isa<AddrLabelExpr>(stackE)) { // address of label.
4911 S.Diag(diagLoc, diag::warn_ret_addr_label) << diagRange;
4912 } else { // local temporary.
4913 S.Diag(diagLoc, lhsType->isReferenceType() ? diag::warn_ret_local_temp_ref
4914 : diag::warn_ret_local_temp_addr)
4918 // Display the "trail" of reference variables that we followed until we
4919 // found the problematic expression using notes.
4920 for (unsigned i = 0, e = refVars.size(); i != e; ++i) {
4921 VarDecl *VD = cast<VarDecl>(refVars[i]->getDecl());
4922 // If this var binds to another reference var, show the range of the next
4923 // var, otherwise the var binds to the problematic expression, in which case
4924 // show the range of the expression.
4925 SourceRange range = (i < e-1) ? refVars[i+1]->getSourceRange()
4926 : stackE->getSourceRange();
4927 S.Diag(VD->getLocation(), diag::note_ref_var_local_bind)
4928 << VD->getDeclName() << range;
4932 /// EvalAddr - EvalAddr and EvalVal are mutually recursive functions that
4933 /// check if the expression in a return statement evaluates to an address
4934 /// to a location on the stack, a local block, an address of a label, or a
4935 /// reference to local temporary. The recursion is used to traverse the
4936 /// AST of the return expression, with recursion backtracking when we
4937 /// encounter a subexpression that (1) clearly does not lead to one of the
4938 /// above problematic expressions (2) is something we cannot determine leads to
4939 /// a problematic expression based on such local checking.
4941 /// Both EvalAddr and EvalVal follow through reference variables to evaluate
4942 /// the expression that they point to. Such variables are added to the
4943 /// 'refVars' vector so that we know what the reference variable "trail" was.
4945 /// EvalAddr processes expressions that are pointers that are used as
4946 /// references (and not L-values). EvalVal handles all other values.
4947 /// At the base case of the recursion is a check for the above problematic
4950 /// This implementation handles:
4952 /// * pointer-to-pointer casts
4953 /// * implicit conversions from array references to pointers
4954 /// * taking the address of fields
4955 /// * arbitrary interplay between "&" and "*" operators
4956 /// * pointer arithmetic from an address of a stack variable
4957 /// * taking the address of an array element where the array is on the stack
4958 static Expr *EvalAddr(Expr *E, SmallVectorImpl<DeclRefExpr *> &refVars,
4960 if (E->isTypeDependent())
4963 // We should only be called for evaluating pointer expressions.
4964 assert((E->getType()->isAnyPointerType() ||
4965 E->getType()->isBlockPointerType() ||
4966 E->getType()->isObjCQualifiedIdType()) &&
4967 "EvalAddr only works on pointers");
4969 E = E->IgnoreParens();
4971 // Our "symbolic interpreter" is just a dispatch off the currently
4972 // viewed AST node. We then recursively traverse the AST by calling
4973 // EvalAddr and EvalVal appropriately.
4974 switch (E->getStmtClass()) {
4975 case Stmt::DeclRefExprClass: {
4976 DeclRefExpr *DR = cast<DeclRefExpr>(E);
4978 // If we leave the immediate function, the lifetime isn't about to end.
4979 if (DR->refersToEnclosingVariableOrCapture())
4982 if (VarDecl *V = dyn_cast<VarDecl>(DR->getDecl()))
4983 // If this is a reference variable, follow through to the expression that
4985 if (V->hasLocalStorage() &&
4986 V->getType()->isReferenceType() && V->hasInit()) {
4987 // Add the reference variable to the "trail".
4988 refVars.push_back(DR);
4989 return EvalAddr(V->getInit(), refVars, ParentDecl);
4995 case Stmt::UnaryOperatorClass: {
4996 // The only unary operator that make sense to handle here
4997 // is AddrOf. All others don't make sense as pointers.
4998 UnaryOperator *U = cast<UnaryOperator>(E);
5000 if (U->getOpcode() == UO_AddrOf)
5001 return EvalVal(U->getSubExpr(), refVars, ParentDecl);
5006 case Stmt::BinaryOperatorClass: {
5007 // Handle pointer arithmetic. All other binary operators are not valid
5009 BinaryOperator *B = cast<BinaryOperator>(E);
5010 BinaryOperatorKind op = B->getOpcode();
5012 if (op != BO_Add && op != BO_Sub)
5015 Expr *Base = B->getLHS();
5017 // Determine which argument is the real pointer base. It could be
5018 // the RHS argument instead of the LHS.
5019 if (!Base->getType()->isPointerType()) Base = B->getRHS();
5021 assert (Base->getType()->isPointerType());
5022 return EvalAddr(Base, refVars, ParentDecl);
5025 // For conditional operators we need to see if either the LHS or RHS are
5026 // valid DeclRefExpr*s. If one of them is valid, we return it.
5027 case Stmt::ConditionalOperatorClass: {
5028 ConditionalOperator *C = cast<ConditionalOperator>(E);
5030 // Handle the GNU extension for missing LHS.
5031 // FIXME: That isn't a ConditionalOperator, so doesn't get here.
5032 if (Expr *LHSExpr = C->getLHS()) {
5033 // In C++, we can have a throw-expression, which has 'void' type.
5034 if (!LHSExpr->getType()->isVoidType())
5035 if (Expr *LHS = EvalAddr(LHSExpr, refVars, ParentDecl))
5039 // In C++, we can have a throw-expression, which has 'void' type.
5040 if (C->getRHS()->getType()->isVoidType())
5043 return EvalAddr(C->getRHS(), refVars, ParentDecl);
5046 case Stmt::BlockExprClass:
5047 if (cast<BlockExpr>(E)->getBlockDecl()->hasCaptures())
5048 return E; // local block.
5051 case Stmt::AddrLabelExprClass:
5052 return E; // address of label.
5054 case Stmt::ExprWithCleanupsClass:
5055 return EvalAddr(cast<ExprWithCleanups>(E)->getSubExpr(), refVars,
5058 // For casts, we need to handle conversions from arrays to
5059 // pointer values, and pointer-to-pointer conversions.
5060 case Stmt::ImplicitCastExprClass:
5061 case Stmt::CStyleCastExprClass:
5062 case Stmt::CXXFunctionalCastExprClass:
5063 case Stmt::ObjCBridgedCastExprClass:
5064 case Stmt::CXXStaticCastExprClass:
5065 case Stmt::CXXDynamicCastExprClass:
5066 case Stmt::CXXConstCastExprClass:
5067 case Stmt::CXXReinterpretCastExprClass: {
5068 Expr* SubExpr = cast<CastExpr>(E)->getSubExpr();
5069 switch (cast<CastExpr>(E)->getCastKind()) {
5070 case CK_LValueToRValue:
5072 case CK_BaseToDerived:
5073 case CK_DerivedToBase:
5074 case CK_UncheckedDerivedToBase:
5076 case CK_CPointerToObjCPointerCast:
5077 case CK_BlockPointerToObjCPointerCast:
5078 case CK_AnyPointerToBlockPointerCast:
5079 return EvalAddr(SubExpr, refVars, ParentDecl);
5081 case CK_ArrayToPointerDecay:
5082 return EvalVal(SubExpr, refVars, ParentDecl);
5085 if (SubExpr->getType()->isAnyPointerType() ||
5086 SubExpr->getType()->isBlockPointerType() ||
5087 SubExpr->getType()->isObjCQualifiedIdType())
5088 return EvalAddr(SubExpr, refVars, ParentDecl);
5097 case Stmt::MaterializeTemporaryExprClass:
5098 if (Expr *Result = EvalAddr(
5099 cast<MaterializeTemporaryExpr>(E)->GetTemporaryExpr(),
5100 refVars, ParentDecl))
5105 // Everything else: we simply don't reason about them.
5112 /// EvalVal - This function is complements EvalAddr in the mutual recursion.
5113 /// See the comments for EvalAddr for more details.
5114 static Expr *EvalVal(Expr *E, SmallVectorImpl<DeclRefExpr *> &refVars,
5117 // We should only be called for evaluating non-pointer expressions, or
5118 // expressions with a pointer type that are not used as references but instead
5119 // are l-values (e.g., DeclRefExpr with a pointer type).
5121 // Our "symbolic interpreter" is just a dispatch off the currently
5122 // viewed AST node. We then recursively traverse the AST by calling
5123 // EvalAddr and EvalVal appropriately.
5125 E = E->IgnoreParens();
5126 switch (E->getStmtClass()) {
5127 case Stmt::ImplicitCastExprClass: {
5128 ImplicitCastExpr *IE = cast<ImplicitCastExpr>(E);
5129 if (IE->getValueKind() == VK_LValue) {
5130 E = IE->getSubExpr();
5136 case Stmt::ExprWithCleanupsClass:
5137 return EvalVal(cast<ExprWithCleanups>(E)->getSubExpr(), refVars,ParentDecl);
5139 case Stmt::DeclRefExprClass: {
5140 // When we hit a DeclRefExpr we are looking at code that refers to a
5141 // variable's name. If it's not a reference variable we check if it has
5142 // local storage within the function, and if so, return the expression.
5143 DeclRefExpr *DR = cast<DeclRefExpr>(E);
5145 // If we leave the immediate function, the lifetime isn't about to end.
5146 if (DR->refersToEnclosingVariableOrCapture())
5149 if (VarDecl *V = dyn_cast<VarDecl>(DR->getDecl())) {
5150 // Check if it refers to itself, e.g. "int& i = i;".
5151 if (V == ParentDecl)
5154 if (V->hasLocalStorage()) {
5155 if (!V->getType()->isReferenceType())
5158 // Reference variable, follow through to the expression that
5161 // Add the reference variable to the "trail".
5162 refVars.push_back(DR);
5163 return EvalVal(V->getInit(), refVars, V);
5171 case Stmt::UnaryOperatorClass: {
5172 // The only unary operator that make sense to handle here
5173 // is Deref. All others don't resolve to a "name." This includes
5174 // handling all sorts of rvalues passed to a unary operator.
5175 UnaryOperator *U = cast<UnaryOperator>(E);
5177 if (U->getOpcode() == UO_Deref)
5178 return EvalAddr(U->getSubExpr(), refVars, ParentDecl);
5183 case Stmt::ArraySubscriptExprClass: {
5184 // Array subscripts are potential references to data on the stack. We
5185 // retrieve the DeclRefExpr* for the array variable if it indeed
5186 // has local storage.
5187 return EvalAddr(cast<ArraySubscriptExpr>(E)->getBase(), refVars,ParentDecl);
5190 case Stmt::ConditionalOperatorClass: {
5191 // For conditional operators we need to see if either the LHS or RHS are
5192 // non-NULL Expr's. If one is non-NULL, we return it.
5193 ConditionalOperator *C = cast<ConditionalOperator>(E);
5195 // Handle the GNU extension for missing LHS.
5196 if (Expr *LHSExpr = C->getLHS()) {
5197 // In C++, we can have a throw-expression, which has 'void' type.
5198 if (!LHSExpr->getType()->isVoidType())
5199 if (Expr *LHS = EvalVal(LHSExpr, refVars, ParentDecl))
5203 // In C++, we can have a throw-expression, which has 'void' type.
5204 if (C->getRHS()->getType()->isVoidType())
5207 return EvalVal(C->getRHS(), refVars, ParentDecl);
5210 // Accesses to members are potential references to data on the stack.
5211 case Stmt::MemberExprClass: {
5212 MemberExpr *M = cast<MemberExpr>(E);
5214 // Check for indirect access. We only want direct field accesses.
5218 // Check whether the member type is itself a reference, in which case
5219 // we're not going to refer to the member, but to what the member refers to.
5220 if (M->getMemberDecl()->getType()->isReferenceType())
5223 return EvalVal(M->getBase(), refVars, ParentDecl);
5226 case Stmt::MaterializeTemporaryExprClass:
5227 if (Expr *Result = EvalVal(
5228 cast<MaterializeTemporaryExpr>(E)->GetTemporaryExpr(),
5229 refVars, ParentDecl))
5235 // Check that we don't return or take the address of a reference to a
5236 // temporary. This is only useful in C++.
5237 if (!E->isTypeDependent() && E->isRValue())
5240 // Everything else: we simply don't reason about them.
5247 Sema::CheckReturnValExpr(Expr *RetValExp, QualType lhsType,
5248 SourceLocation ReturnLoc,
5250 const AttrVec *Attrs,
5251 const FunctionDecl *FD) {
5252 CheckReturnStackAddr(*this, RetValExp, lhsType, ReturnLoc);
5254 // Check if the return value is null but should not be.
5255 if (Attrs && hasSpecificAttr<ReturnsNonNullAttr>(*Attrs) &&
5256 CheckNonNullExpr(*this, RetValExp))
5257 Diag(ReturnLoc, diag::warn_null_ret)
5258 << (isObjCMethod ? 1 : 0) << RetValExp->getSourceRange();
5260 // C++11 [basic.stc.dynamic.allocation]p4:
5261 // If an allocation function declared with a non-throwing
5262 // exception-specification fails to allocate storage, it shall return
5263 // a null pointer. Any other allocation function that fails to allocate
5264 // storage shall indicate failure only by throwing an exception [...]
5266 OverloadedOperatorKind Op = FD->getOverloadedOperator();
5267 if (Op == OO_New || Op == OO_Array_New) {
5268 const FunctionProtoType *Proto
5269 = FD->getType()->castAs<FunctionProtoType>();
5270 if (!Proto->isNothrow(Context, /*ResultIfDependent*/true) &&
5271 CheckNonNullExpr(*this, RetValExp))
5272 Diag(ReturnLoc, diag::warn_operator_new_returns_null)
5273 << FD << getLangOpts().CPlusPlus11;
5278 //===--- CHECK: Floating-Point comparisons (-Wfloat-equal) ---------------===//
5280 /// Check for comparisons of floating point operands using != and ==.
5281 /// Issue a warning if these are no self-comparisons, as they are not likely
5282 /// to do what the programmer intended.
5283 void Sema::CheckFloatComparison(SourceLocation Loc, Expr* LHS, Expr *RHS) {
5284 Expr* LeftExprSansParen = LHS->IgnoreParenImpCasts();
5285 Expr* RightExprSansParen = RHS->IgnoreParenImpCasts();
5287 // Special case: check for x == x (which is OK).
5288 // Do not emit warnings for such cases.
5289 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LeftExprSansParen))
5290 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RightExprSansParen))
5291 if (DRL->getDecl() == DRR->getDecl())
5295 // Special case: check for comparisons against literals that can be exactly
5296 // represented by APFloat. In such cases, do not emit a warning. This
5297 // is a heuristic: often comparison against such literals are used to
5298 // detect if a value in a variable has not changed. This clearly can
5299 // lead to false negatives.
5300 if (FloatingLiteral* FLL = dyn_cast<FloatingLiteral>(LeftExprSansParen)) {
5304 if (FloatingLiteral* FLR = dyn_cast<FloatingLiteral>(RightExprSansParen))
5308 // Check for comparisons with builtin types.
5309 if (CallExpr* CL = dyn_cast<CallExpr>(LeftExprSansParen))
5310 if (CL->getBuiltinCallee())
5313 if (CallExpr* CR = dyn_cast<CallExpr>(RightExprSansParen))
5314 if (CR->getBuiltinCallee())
5317 // Emit the diagnostic.
5318 Diag(Loc, diag::warn_floatingpoint_eq)
5319 << LHS->getSourceRange() << RHS->getSourceRange();
5322 //===--- CHECK: Integer mixed-sign comparisons (-Wsign-compare) --------===//
5323 //===--- CHECK: Lossy implicit conversions (-Wconversion) --------------===//
5327 /// Structure recording the 'active' range of an integer-valued
5330 /// The number of bits active in the int.
5333 /// True if the int is known not to have negative values.
5336 IntRange(unsigned Width, bool NonNegative)
5337 : Width(Width), NonNegative(NonNegative)
5340 /// Returns the range of the bool type.
5341 static IntRange forBoolType() {
5342 return IntRange(1, true);
5345 /// Returns the range of an opaque value of the given integral type.
5346 static IntRange forValueOfType(ASTContext &C, QualType T) {
5347 return forValueOfCanonicalType(C,
5348 T->getCanonicalTypeInternal().getTypePtr());
5351 /// Returns the range of an opaque value of a canonical integral type.
5352 static IntRange forValueOfCanonicalType(ASTContext &C, const Type *T) {
5353 assert(T->isCanonicalUnqualified());
5355 if (const VectorType *VT = dyn_cast<VectorType>(T))
5356 T = VT->getElementType().getTypePtr();
5357 if (const ComplexType *CT = dyn_cast<ComplexType>(T))
5358 T = CT->getElementType().getTypePtr();
5359 if (const AtomicType *AT = dyn_cast<AtomicType>(T))
5360 T = AT->getValueType().getTypePtr();
5362 // For enum types, use the known bit width of the enumerators.
5363 if (const EnumType *ET = dyn_cast<EnumType>(T)) {
5364 EnumDecl *Enum = ET->getDecl();
5365 if (!Enum->isCompleteDefinition())
5366 return IntRange(C.getIntWidth(QualType(T, 0)), false);
5368 unsigned NumPositive = Enum->getNumPositiveBits();
5369 unsigned NumNegative = Enum->getNumNegativeBits();
5371 if (NumNegative == 0)
5372 return IntRange(NumPositive, true/*NonNegative*/);
5374 return IntRange(std::max(NumPositive + 1, NumNegative),
5375 false/*NonNegative*/);
5378 const BuiltinType *BT = cast<BuiltinType>(T);
5379 assert(BT->isInteger());
5381 return IntRange(C.getIntWidth(QualType(T, 0)), BT->isUnsignedInteger());
5384 /// Returns the "target" range of a canonical integral type, i.e.
5385 /// the range of values expressible in the type.
5387 /// This matches forValueOfCanonicalType except that enums have the
5388 /// full range of their type, not the range of their enumerators.
5389 static IntRange forTargetOfCanonicalType(ASTContext &C, const Type *T) {
5390 assert(T->isCanonicalUnqualified());
5392 if (const VectorType *VT = dyn_cast<VectorType>(T))
5393 T = VT->getElementType().getTypePtr();
5394 if (const ComplexType *CT = dyn_cast<ComplexType>(T))
5395 T = CT->getElementType().getTypePtr();
5396 if (const AtomicType *AT = dyn_cast<AtomicType>(T))
5397 T = AT->getValueType().getTypePtr();
5398 if (const EnumType *ET = dyn_cast<EnumType>(T))
5399 T = C.getCanonicalType(ET->getDecl()->getIntegerType()).getTypePtr();
5401 const BuiltinType *BT = cast<BuiltinType>(T);
5402 assert(BT->isInteger());
5404 return IntRange(C.getIntWidth(QualType(T, 0)), BT->isUnsignedInteger());
5407 /// Returns the supremum of two ranges: i.e. their conservative merge.
5408 static IntRange join(IntRange L, IntRange R) {
5409 return IntRange(std::max(L.Width, R.Width),
5410 L.NonNegative && R.NonNegative);
5413 /// Returns the infinum of two ranges: i.e. their aggressive merge.
5414 static IntRange meet(IntRange L, IntRange R) {
5415 return IntRange(std::min(L.Width, R.Width),
5416 L.NonNegative || R.NonNegative);
5420 static IntRange GetValueRange(ASTContext &C, llvm::APSInt &value,
5421 unsigned MaxWidth) {
5422 if (value.isSigned() && value.isNegative())
5423 return IntRange(value.getMinSignedBits(), false);
5425 if (value.getBitWidth() > MaxWidth)
5426 value = value.trunc(MaxWidth);
5428 // isNonNegative() just checks the sign bit without considering
5430 return IntRange(value.getActiveBits(), true);
5433 static IntRange GetValueRange(ASTContext &C, APValue &result, QualType Ty,
5434 unsigned MaxWidth) {
5436 return GetValueRange(C, result.getInt(), MaxWidth);
5438 if (result.isVector()) {
5439 IntRange R = GetValueRange(C, result.getVectorElt(0), Ty, MaxWidth);
5440 for (unsigned i = 1, e = result.getVectorLength(); i != e; ++i) {
5441 IntRange El = GetValueRange(C, result.getVectorElt(i), Ty, MaxWidth);
5442 R = IntRange::join(R, El);
5447 if (result.isComplexInt()) {
5448 IntRange R = GetValueRange(C, result.getComplexIntReal(), MaxWidth);
5449 IntRange I = GetValueRange(C, result.getComplexIntImag(), MaxWidth);
5450 return IntRange::join(R, I);
5453 // This can happen with lossless casts to intptr_t of "based" lvalues.
5454 // Assume it might use arbitrary bits.
5455 // FIXME: The only reason we need to pass the type in here is to get
5456 // the sign right on this one case. It would be nice if APValue
5458 assert(result.isLValue() || result.isAddrLabelDiff());
5459 return IntRange(MaxWidth, Ty->isUnsignedIntegerOrEnumerationType());
5462 static QualType GetExprType(Expr *E) {
5463 QualType Ty = E->getType();
5464 if (const AtomicType *AtomicRHS = Ty->getAs<AtomicType>())
5465 Ty = AtomicRHS->getValueType();
5469 /// Pseudo-evaluate the given integer expression, estimating the
5470 /// range of values it might take.
5472 /// \param MaxWidth - the width to which the value will be truncated
5473 static IntRange GetExprRange(ASTContext &C, Expr *E, unsigned MaxWidth) {
5474 E = E->IgnoreParens();
5476 // Try a full evaluation first.
5477 Expr::EvalResult result;
5478 if (E->EvaluateAsRValue(result, C))
5479 return GetValueRange(C, result.Val, GetExprType(E), MaxWidth);
5481 // I think we only want to look through implicit casts here; if the
5482 // user has an explicit widening cast, we should treat the value as
5483 // being of the new, wider type.
5484 if (ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(E)) {
5485 if (CE->getCastKind() == CK_NoOp || CE->getCastKind() == CK_LValueToRValue)
5486 return GetExprRange(C, CE->getSubExpr(), MaxWidth);
5488 IntRange OutputTypeRange = IntRange::forValueOfType(C, GetExprType(CE));
5490 bool isIntegerCast = (CE->getCastKind() == CK_IntegralCast);
5492 // Assume that non-integer casts can span the full range of the type.
5494 return OutputTypeRange;
5497 = GetExprRange(C, CE->getSubExpr(),
5498 std::min(MaxWidth, OutputTypeRange.Width));
5500 // Bail out if the subexpr's range is as wide as the cast type.
5501 if (SubRange.Width >= OutputTypeRange.Width)
5502 return OutputTypeRange;
5504 // Otherwise, we take the smaller width, and we're non-negative if
5505 // either the output type or the subexpr is.
5506 return IntRange(SubRange.Width,
5507 SubRange.NonNegative || OutputTypeRange.NonNegative);
5510 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
5511 // If we can fold the condition, just take that operand.
5513 if (CO->getCond()->EvaluateAsBooleanCondition(CondResult, C))
5514 return GetExprRange(C, CondResult ? CO->getTrueExpr()
5515 : CO->getFalseExpr(),
5518 // Otherwise, conservatively merge.
5519 IntRange L = GetExprRange(C, CO->getTrueExpr(), MaxWidth);
5520 IntRange R = GetExprRange(C, CO->getFalseExpr(), MaxWidth);
5521 return IntRange::join(L, R);
5524 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
5525 switch (BO->getOpcode()) {
5527 // Boolean-valued operations are single-bit and positive.
5536 return IntRange::forBoolType();
5538 // The type of the assignments is the type of the LHS, so the RHS
5539 // is not necessarily the same type.
5548 return IntRange::forValueOfType(C, GetExprType(E));
5550 // Simple assignments just pass through the RHS, which will have
5551 // been coerced to the LHS type.
5554 return GetExprRange(C, BO->getRHS(), MaxWidth);
5556 // Operations with opaque sources are black-listed.
5559 return IntRange::forValueOfType(C, GetExprType(E));
5561 // Bitwise-and uses the *infinum* of the two source ranges.
5564 return IntRange::meet(GetExprRange(C, BO->getLHS(), MaxWidth),
5565 GetExprRange(C, BO->getRHS(), MaxWidth));
5567 // Left shift gets black-listed based on a judgement call.
5569 // ...except that we want to treat '1 << (blah)' as logically
5570 // positive. It's an important idiom.
5571 if (IntegerLiteral *I
5572 = dyn_cast<IntegerLiteral>(BO->getLHS()->IgnoreParenCasts())) {
5573 if (I->getValue() == 1) {
5574 IntRange R = IntRange::forValueOfType(C, GetExprType(E));
5575 return IntRange(R.Width, /*NonNegative*/ true);
5581 return IntRange::forValueOfType(C, GetExprType(E));
5583 // Right shift by a constant can narrow its left argument.
5585 case BO_ShrAssign: {
5586 IntRange L = GetExprRange(C, BO->getLHS(), MaxWidth);
5588 // If the shift amount is a positive constant, drop the width by
5591 if (BO->getRHS()->isIntegerConstantExpr(shift, C) &&
5592 shift.isNonNegative()) {
5593 unsigned zext = shift.getZExtValue();
5594 if (zext >= L.Width)
5595 L.Width = (L.NonNegative ? 0 : 1);
5603 // Comma acts as its right operand.
5605 return GetExprRange(C, BO->getRHS(), MaxWidth);
5607 // Black-list pointer subtractions.
5609 if (BO->getLHS()->getType()->isPointerType())
5610 return IntRange::forValueOfType(C, GetExprType(E));
5613 // The width of a division result is mostly determined by the size
5616 // Don't 'pre-truncate' the operands.
5617 unsigned opWidth = C.getIntWidth(GetExprType(E));
5618 IntRange L = GetExprRange(C, BO->getLHS(), opWidth);
5620 // If the divisor is constant, use that.
5621 llvm::APSInt divisor;
5622 if (BO->getRHS()->isIntegerConstantExpr(divisor, C)) {
5623 unsigned log2 = divisor.logBase2(); // floor(log_2(divisor))
5624 if (log2 >= L.Width)
5625 L.Width = (L.NonNegative ? 0 : 1);
5627 L.Width = std::min(L.Width - log2, MaxWidth);
5631 // Otherwise, just use the LHS's width.
5632 IntRange R = GetExprRange(C, BO->getRHS(), opWidth);
5633 return IntRange(L.Width, L.NonNegative && R.NonNegative);
5636 // The result of a remainder can't be larger than the result of
5639 // Don't 'pre-truncate' the operands.
5640 unsigned opWidth = C.getIntWidth(GetExprType(E));
5641 IntRange L = GetExprRange(C, BO->getLHS(), opWidth);
5642 IntRange R = GetExprRange(C, BO->getRHS(), opWidth);
5644 IntRange meet = IntRange::meet(L, R);
5645 meet.Width = std::min(meet.Width, MaxWidth);
5649 // The default behavior is okay for these.
5657 // The default case is to treat the operation as if it were closed
5658 // on the narrowest type that encompasses both operands.
5659 IntRange L = GetExprRange(C, BO->getLHS(), MaxWidth);
5660 IntRange R = GetExprRange(C, BO->getRHS(), MaxWidth);
5661 return IntRange::join(L, R);
5664 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
5665 switch (UO->getOpcode()) {
5666 // Boolean-valued operations are white-listed.
5668 return IntRange::forBoolType();
5670 // Operations with opaque sources are black-listed.
5672 case UO_AddrOf: // should be impossible
5673 return IntRange::forValueOfType(C, GetExprType(E));
5676 return GetExprRange(C, UO->getSubExpr(), MaxWidth);
5680 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E))
5681 return GetExprRange(C, OVE->getSourceExpr(), MaxWidth);
5683 if (FieldDecl *BitField = E->getSourceBitField())
5684 return IntRange(BitField->getBitWidthValue(C),
5685 BitField->getType()->isUnsignedIntegerOrEnumerationType());
5687 return IntRange::forValueOfType(C, GetExprType(E));
5690 static IntRange GetExprRange(ASTContext &C, Expr *E) {
5691 return GetExprRange(C, E, C.getIntWidth(GetExprType(E)));
5694 /// Checks whether the given value, which currently has the given
5695 /// source semantics, has the same value when coerced through the
5696 /// target semantics.
5697 static bool IsSameFloatAfterCast(const llvm::APFloat &value,
5698 const llvm::fltSemantics &Src,
5699 const llvm::fltSemantics &Tgt) {
5700 llvm::APFloat truncated = value;
5703 truncated.convert(Src, llvm::APFloat::rmNearestTiesToEven, &ignored);
5704 truncated.convert(Tgt, llvm::APFloat::rmNearestTiesToEven, &ignored);
5706 return truncated.bitwiseIsEqual(value);
5709 /// Checks whether the given value, which currently has the given
5710 /// source semantics, has the same value when coerced through the
5711 /// target semantics.
5713 /// The value might be a vector of floats (or a complex number).
5714 static bool IsSameFloatAfterCast(const APValue &value,
5715 const llvm::fltSemantics &Src,
5716 const llvm::fltSemantics &Tgt) {
5717 if (value.isFloat())
5718 return IsSameFloatAfterCast(value.getFloat(), Src, Tgt);
5720 if (value.isVector()) {
5721 for (unsigned i = 0, e = value.getVectorLength(); i != e; ++i)
5722 if (!IsSameFloatAfterCast(value.getVectorElt(i), Src, Tgt))
5727 assert(value.isComplexFloat());
5728 return (IsSameFloatAfterCast(value.getComplexFloatReal(), Src, Tgt) &&
5729 IsSameFloatAfterCast(value.getComplexFloatImag(), Src, Tgt));
5732 static void AnalyzeImplicitConversions(Sema &S, Expr *E, SourceLocation CC);
5734 static bool IsZero(Sema &S, Expr *E) {
5735 // Suppress cases where we are comparing against an enum constant.
5736 if (const DeclRefExpr *DR =
5737 dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts()))
5738 if (isa<EnumConstantDecl>(DR->getDecl()))
5741 // Suppress cases where the '0' value is expanded from a macro.
5742 if (E->getLocStart().isMacroID())
5746 return E->isIntegerConstantExpr(Value, S.Context) && Value == 0;
5749 static bool HasEnumType(Expr *E) {
5750 // Strip off implicit integral promotions.
5751 while (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) {
5752 if (ICE->getCastKind() != CK_IntegralCast &&
5753 ICE->getCastKind() != CK_NoOp)
5755 E = ICE->getSubExpr();
5758 return E->getType()->isEnumeralType();
5761 static void CheckTrivialUnsignedComparison(Sema &S, BinaryOperator *E) {
5762 // Disable warning in template instantiations.
5763 if (!S.ActiveTemplateInstantiations.empty())
5766 BinaryOperatorKind op = E->getOpcode();
5767 if (E->isValueDependent())
5770 if (op == BO_LT && IsZero(S, E->getRHS())) {
5771 S.Diag(E->getOperatorLoc(), diag::warn_lunsigned_always_true_comparison)
5772 << "< 0" << "false" << HasEnumType(E->getLHS())
5773 << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange();
5774 } else if (op == BO_GE && IsZero(S, E->getRHS())) {
5775 S.Diag(E->getOperatorLoc(), diag::warn_lunsigned_always_true_comparison)
5776 << ">= 0" << "true" << HasEnumType(E->getLHS())
5777 << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange();
5778 } else if (op == BO_GT && IsZero(S, E->getLHS())) {
5779 S.Diag(E->getOperatorLoc(), diag::warn_runsigned_always_true_comparison)
5780 << "0 >" << "false" << HasEnumType(E->getRHS())
5781 << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange();
5782 } else if (op == BO_LE && IsZero(S, E->getLHS())) {
5783 S.Diag(E->getOperatorLoc(), diag::warn_runsigned_always_true_comparison)
5784 << "0 <=" << "true" << HasEnumType(E->getRHS())
5785 << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange();
5789 static void DiagnoseOutOfRangeComparison(Sema &S, BinaryOperator *E,
5790 Expr *Constant, Expr *Other,
5793 // Disable warning in template instantiations.
5794 if (!S.ActiveTemplateInstantiations.empty())
5797 // TODO: Investigate using GetExprRange() to get tighter bounds
5798 // on the bit ranges.
5799 QualType OtherT = Other->getType();
5800 if (const AtomicType *AT = dyn_cast<AtomicType>(OtherT))
5801 OtherT = AT->getValueType();
5802 IntRange OtherRange = IntRange::forValueOfType(S.Context, OtherT);
5803 unsigned OtherWidth = OtherRange.Width;
5805 bool OtherIsBooleanType = Other->isKnownToHaveBooleanValue();
5807 // 0 values are handled later by CheckTrivialUnsignedComparison().
5808 if ((Value == 0) && (!OtherIsBooleanType))
5811 BinaryOperatorKind op = E->getOpcode();
5814 // Used for diagnostic printout.
5816 LiteralConstant = 0,
5819 } LiteralOrBoolConstant = LiteralConstant;
5821 if (!OtherIsBooleanType) {
5822 QualType ConstantT = Constant->getType();
5823 QualType CommonT = E->getLHS()->getType();
5825 if (S.Context.hasSameUnqualifiedType(OtherT, ConstantT))
5827 assert((OtherT->isIntegerType() && ConstantT->isIntegerType()) &&
5828 "comparison with non-integer type");
5830 bool ConstantSigned = ConstantT->isSignedIntegerType();
5831 bool CommonSigned = CommonT->isSignedIntegerType();
5833 bool EqualityOnly = false;
5836 // The common type is signed, therefore no signed to unsigned conversion.
5837 if (!OtherRange.NonNegative) {
5838 // Check that the constant is representable in type OtherT.
5839 if (ConstantSigned) {
5840 if (OtherWidth >= Value.getMinSignedBits())
5842 } else { // !ConstantSigned
5843 if (OtherWidth >= Value.getActiveBits() + 1)
5846 } else { // !OtherSigned
5847 // Check that the constant is representable in type OtherT.
5848 // Negative values are out of range.
5849 if (ConstantSigned) {
5850 if (Value.isNonNegative() && OtherWidth >= Value.getActiveBits())
5852 } else { // !ConstantSigned
5853 if (OtherWidth >= Value.getActiveBits())
5857 } else { // !CommonSigned
5858 if (OtherRange.NonNegative) {
5859 if (OtherWidth >= Value.getActiveBits())
5861 } else { // OtherSigned
5862 assert(!ConstantSigned &&
5863 "Two signed types converted to unsigned types.");
5864 // Check to see if the constant is representable in OtherT.
5865 if (OtherWidth > Value.getActiveBits())
5867 // Check to see if the constant is equivalent to a negative value
5869 if (S.Context.getIntWidth(ConstantT) ==
5870 S.Context.getIntWidth(CommonT) &&
5871 Value.isNegative() && Value.getMinSignedBits() <= OtherWidth)
5873 // The constant value rests between values that OtherT can represent
5874 // after conversion. Relational comparison still works, but equality
5875 // comparisons will be tautological.
5876 EqualityOnly = true;
5880 bool PositiveConstant = !ConstantSigned || Value.isNonNegative();
5882 if (op == BO_EQ || op == BO_NE) {
5883 IsTrue = op == BO_NE;
5884 } else if (EqualityOnly) {
5886 } else if (RhsConstant) {
5887 if (op == BO_GT || op == BO_GE)
5888 IsTrue = !PositiveConstant;
5889 else // op == BO_LT || op == BO_LE
5890 IsTrue = PositiveConstant;
5892 if (op == BO_LT || op == BO_LE)
5893 IsTrue = !PositiveConstant;
5894 else // op == BO_GT || op == BO_GE
5895 IsTrue = PositiveConstant;
5898 // Other isKnownToHaveBooleanValue
5899 enum CompareBoolWithConstantResult { AFals, ATrue, Unkwn };
5900 enum ConstantValue { LT_Zero, Zero, One, GT_One, SizeOfConstVal };
5901 enum ConstantSide { Lhs, Rhs, SizeOfConstSides };
5903 static const struct LinkedConditions {
5904 CompareBoolWithConstantResult BO_LT_OP[SizeOfConstSides][SizeOfConstVal];
5905 CompareBoolWithConstantResult BO_GT_OP[SizeOfConstSides][SizeOfConstVal];
5906 CompareBoolWithConstantResult BO_LE_OP[SizeOfConstSides][SizeOfConstVal];
5907 CompareBoolWithConstantResult BO_GE_OP[SizeOfConstSides][SizeOfConstVal];
5908 CompareBoolWithConstantResult BO_EQ_OP[SizeOfConstSides][SizeOfConstVal];
5909 CompareBoolWithConstantResult BO_NE_OP[SizeOfConstSides][SizeOfConstVal];
5912 // Constant on LHS. | Constant on RHS. |
5913 // LT_Zero| Zero | One |GT_One| LT_Zero| Zero | One |GT_One|
5914 { { ATrue, Unkwn, AFals, AFals }, { AFals, AFals, Unkwn, ATrue } },
5915 { { AFals, AFals, Unkwn, ATrue }, { ATrue, Unkwn, AFals, AFals } },
5916 { { ATrue, ATrue, Unkwn, AFals }, { AFals, Unkwn, ATrue, ATrue } },
5917 { { AFals, Unkwn, ATrue, ATrue }, { ATrue, ATrue, Unkwn, AFals } },
5918 { { AFals, Unkwn, Unkwn, AFals }, { AFals, Unkwn, Unkwn, AFals } },
5919 { { ATrue, Unkwn, Unkwn, ATrue }, { ATrue, Unkwn, Unkwn, ATrue } }
5922 bool ConstantIsBoolLiteral = isa<CXXBoolLiteralExpr>(Constant);
5924 enum ConstantValue ConstVal = Zero;
5925 if (Value.isUnsigned() || Value.isNonNegative()) {
5927 LiteralOrBoolConstant =
5928 ConstantIsBoolLiteral ? CXXBoolLiteralFalse : LiteralConstant;
5930 } else if (Value == 1) {
5931 LiteralOrBoolConstant =
5932 ConstantIsBoolLiteral ? CXXBoolLiteralTrue : LiteralConstant;
5935 LiteralOrBoolConstant = LiteralConstant;
5942 CompareBoolWithConstantResult CmpRes;
5946 CmpRes = TruthTable.BO_LT_OP[RhsConstant][ConstVal];
5949 CmpRes = TruthTable.BO_GT_OP[RhsConstant][ConstVal];
5952 CmpRes = TruthTable.BO_LE_OP[RhsConstant][ConstVal];
5955 CmpRes = TruthTable.BO_GE_OP[RhsConstant][ConstVal];
5958 CmpRes = TruthTable.BO_EQ_OP[RhsConstant][ConstVal];
5961 CmpRes = TruthTable.BO_NE_OP[RhsConstant][ConstVal];
5968 if (CmpRes == AFals) {
5970 } else if (CmpRes == ATrue) {
5977 // If this is a comparison to an enum constant, include that
5978 // constant in the diagnostic.
5979 const EnumConstantDecl *ED = nullptr;
5980 if (const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(Constant))
5981 ED = dyn_cast<EnumConstantDecl>(DR->getDecl());
5983 SmallString<64> PrettySourceValue;
5984 llvm::raw_svector_ostream OS(PrettySourceValue);
5986 OS << '\'' << *ED << "' (" << Value << ")";
5990 S.DiagRuntimeBehavior(
5991 E->getOperatorLoc(), E,
5992 S.PDiag(diag::warn_out_of_range_compare)
5993 << OS.str() << LiteralOrBoolConstant
5994 << OtherT << (OtherIsBooleanType && !OtherT->isBooleanType()) << IsTrue
5995 << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange());
5998 /// Analyze the operands of the given comparison. Implements the
5999 /// fallback case from AnalyzeComparison.
6000 static void AnalyzeImpConvsInComparison(Sema &S, BinaryOperator *E) {
6001 AnalyzeImplicitConversions(S, E->getLHS(), E->getOperatorLoc());
6002 AnalyzeImplicitConversions(S, E->getRHS(), E->getOperatorLoc());
6005 /// \brief Implements -Wsign-compare.
6007 /// \param E the binary operator to check for warnings
6008 static void AnalyzeComparison(Sema &S, BinaryOperator *E) {
6009 // The type the comparison is being performed in.
6010 QualType T = E->getLHS()->getType();
6012 // Only analyze comparison operators where both sides have been converted to
6014 if (!S.Context.hasSameUnqualifiedType(T, E->getRHS()->getType()))
6015 return AnalyzeImpConvsInComparison(S, E);
6017 // Don't analyze value-dependent comparisons directly.
6018 if (E->isValueDependent())
6019 return AnalyzeImpConvsInComparison(S, E);
6021 Expr *LHS = E->getLHS()->IgnoreParenImpCasts();
6022 Expr *RHS = E->getRHS()->IgnoreParenImpCasts();
6024 bool IsComparisonConstant = false;
6026 // Check whether an integer constant comparison results in a value
6027 // of 'true' or 'false'.
6028 if (T->isIntegralType(S.Context)) {
6029 llvm::APSInt RHSValue;
6030 bool IsRHSIntegralLiteral =
6031 RHS->isIntegerConstantExpr(RHSValue, S.Context);
6032 llvm::APSInt LHSValue;
6033 bool IsLHSIntegralLiteral =
6034 LHS->isIntegerConstantExpr(LHSValue, S.Context);
6035 if (IsRHSIntegralLiteral && !IsLHSIntegralLiteral)
6036 DiagnoseOutOfRangeComparison(S, E, RHS, LHS, RHSValue, true);
6037 else if (!IsRHSIntegralLiteral && IsLHSIntegralLiteral)
6038 DiagnoseOutOfRangeComparison(S, E, LHS, RHS, LHSValue, false);
6040 IsComparisonConstant =
6041 (IsRHSIntegralLiteral && IsLHSIntegralLiteral);
6042 } else if (!T->hasUnsignedIntegerRepresentation())
6043 IsComparisonConstant = E->isIntegerConstantExpr(S.Context);
6045 // We don't do anything special if this isn't an unsigned integral
6046 // comparison: we're only interested in integral comparisons, and
6047 // signed comparisons only happen in cases we don't care to warn about.
6049 // We also don't care about value-dependent expressions or expressions
6050 // whose result is a constant.
6051 if (!T->hasUnsignedIntegerRepresentation() || IsComparisonConstant)
6052 return AnalyzeImpConvsInComparison(S, E);
6054 // Check to see if one of the (unmodified) operands is of different
6056 Expr *signedOperand, *unsignedOperand;
6057 if (LHS->getType()->hasSignedIntegerRepresentation()) {
6058 assert(!RHS->getType()->hasSignedIntegerRepresentation() &&
6059 "unsigned comparison between two signed integer expressions?");
6060 signedOperand = LHS;
6061 unsignedOperand = RHS;
6062 } else if (RHS->getType()->hasSignedIntegerRepresentation()) {
6063 signedOperand = RHS;
6064 unsignedOperand = LHS;
6066 CheckTrivialUnsignedComparison(S, E);
6067 return AnalyzeImpConvsInComparison(S, E);
6070 // Otherwise, calculate the effective range of the signed operand.
6071 IntRange signedRange = GetExprRange(S.Context, signedOperand);
6073 // Go ahead and analyze implicit conversions in the operands. Note
6074 // that we skip the implicit conversions on both sides.
6075 AnalyzeImplicitConversions(S, LHS, E->getOperatorLoc());
6076 AnalyzeImplicitConversions(S, RHS, E->getOperatorLoc());
6078 // If the signed range is non-negative, -Wsign-compare won't fire,
6079 // but we should still check for comparisons which are always true
6081 if (signedRange.NonNegative)
6082 return CheckTrivialUnsignedComparison(S, E);
6084 // For (in)equality comparisons, if the unsigned operand is a
6085 // constant which cannot collide with a overflowed signed operand,
6086 // then reinterpreting the signed operand as unsigned will not
6087 // change the result of the comparison.
6088 if (E->isEqualityOp()) {
6089 unsigned comparisonWidth = S.Context.getIntWidth(T);
6090 IntRange unsignedRange = GetExprRange(S.Context, unsignedOperand);
6092 // We should never be unable to prove that the unsigned operand is
6094 assert(unsignedRange.NonNegative && "unsigned range includes negative?");
6096 if (unsignedRange.Width < comparisonWidth)
6100 S.DiagRuntimeBehavior(E->getOperatorLoc(), E,
6101 S.PDiag(diag::warn_mixed_sign_comparison)
6102 << LHS->getType() << RHS->getType()
6103 << LHS->getSourceRange() << RHS->getSourceRange());
6106 /// Analyzes an attempt to assign the given value to a bitfield.
6108 /// Returns true if there was something fishy about the attempt.
6109 static bool AnalyzeBitFieldAssignment(Sema &S, FieldDecl *Bitfield, Expr *Init,
6110 SourceLocation InitLoc) {
6111 assert(Bitfield->isBitField());
6112 if (Bitfield->isInvalidDecl())
6115 // White-list bool bitfields.
6116 if (Bitfield->getType()->isBooleanType())
6119 // Ignore value- or type-dependent expressions.
6120 if (Bitfield->getBitWidth()->isValueDependent() ||
6121 Bitfield->getBitWidth()->isTypeDependent() ||
6122 Init->isValueDependent() ||
6123 Init->isTypeDependent())
6126 Expr *OriginalInit = Init->IgnoreParenImpCasts();
6129 if (!OriginalInit->EvaluateAsInt(Value, S.Context, Expr::SE_AllowSideEffects))
6132 unsigned OriginalWidth = Value.getBitWidth();
6133 unsigned FieldWidth = Bitfield->getBitWidthValue(S.Context);
6135 if (OriginalWidth <= FieldWidth)
6138 // Compute the value which the bitfield will contain.
6139 llvm::APSInt TruncatedValue = Value.trunc(FieldWidth);
6140 TruncatedValue.setIsSigned(Bitfield->getType()->isSignedIntegerType());
6142 // Check whether the stored value is equal to the original value.
6143 TruncatedValue = TruncatedValue.extend(OriginalWidth);
6144 if (llvm::APSInt::isSameValue(Value, TruncatedValue))
6147 // Special-case bitfields of width 1: booleans are naturally 0/1, and
6148 // therefore don't strictly fit into a signed bitfield of width 1.
6149 if (FieldWidth == 1 && Value == 1)
6152 std::string PrettyValue = Value.toString(10);
6153 std::string PrettyTrunc = TruncatedValue.toString(10);
6155 S.Diag(InitLoc, diag::warn_impcast_bitfield_precision_constant)
6156 << PrettyValue << PrettyTrunc << OriginalInit->getType()
6157 << Init->getSourceRange();
6162 /// Analyze the given simple or compound assignment for warning-worthy
6164 static void AnalyzeAssignment(Sema &S, BinaryOperator *E) {
6165 // Just recurse on the LHS.
6166 AnalyzeImplicitConversions(S, E->getLHS(), E->getOperatorLoc());
6168 // We want to recurse on the RHS as normal unless we're assigning to
6170 if (FieldDecl *Bitfield = E->getLHS()->getSourceBitField()) {
6171 if (AnalyzeBitFieldAssignment(S, Bitfield, E->getRHS(),
6172 E->getOperatorLoc())) {
6173 // Recurse, ignoring any implicit conversions on the RHS.
6174 return AnalyzeImplicitConversions(S, E->getRHS()->IgnoreParenImpCasts(),
6175 E->getOperatorLoc());
6179 AnalyzeImplicitConversions(S, E->getRHS(), E->getOperatorLoc());
6182 /// Diagnose an implicit cast; purely a helper for CheckImplicitConversion.
6183 static void DiagnoseImpCast(Sema &S, Expr *E, QualType SourceType, QualType T,
6184 SourceLocation CContext, unsigned diag,
6185 bool pruneControlFlow = false) {
6186 if (pruneControlFlow) {
6187 S.DiagRuntimeBehavior(E->getExprLoc(), E,
6189 << SourceType << T << E->getSourceRange()
6190 << SourceRange(CContext));
6193 S.Diag(E->getExprLoc(), diag)
6194 << SourceType << T << E->getSourceRange() << SourceRange(CContext);
6197 /// Diagnose an implicit cast; purely a helper for CheckImplicitConversion.
6198 static void DiagnoseImpCast(Sema &S, Expr *E, QualType T,
6199 SourceLocation CContext, unsigned diag,
6200 bool pruneControlFlow = false) {
6201 DiagnoseImpCast(S, E, E->getType(), T, CContext, diag, pruneControlFlow);
6204 /// Diagnose an implicit cast from a literal expression. Does not warn when the
6205 /// cast wouldn't lose information.
6206 void DiagnoseFloatingLiteralImpCast(Sema &S, FloatingLiteral *FL, QualType T,
6207 SourceLocation CContext) {
6208 // Try to convert the literal exactly to an integer. If we can, don't warn.
6209 bool isExact = false;
6210 const llvm::APFloat &Value = FL->getValue();
6211 llvm::APSInt IntegerValue(S.Context.getIntWidth(T),
6212 T->hasUnsignedIntegerRepresentation());
6213 if (Value.convertToInteger(IntegerValue,
6214 llvm::APFloat::rmTowardZero, &isExact)
6215 == llvm::APFloat::opOK && isExact)
6218 // FIXME: Force the precision of the source value down so we don't print
6219 // digits which are usually useless (we don't really care here if we
6220 // truncate a digit by accident in edge cases). Ideally, APFloat::toString
6221 // would automatically print the shortest representation, but it's a bit
6222 // tricky to implement.
6223 SmallString<16> PrettySourceValue;
6224 unsigned precision = llvm::APFloat::semanticsPrecision(Value.getSemantics());
6225 precision = (precision * 59 + 195) / 196;
6226 Value.toString(PrettySourceValue, precision);
6228 SmallString<16> PrettyTargetValue;
6229 if (T->isSpecificBuiltinType(BuiltinType::Bool))
6230 PrettyTargetValue = IntegerValue == 0 ? "false" : "true";
6232 IntegerValue.toString(PrettyTargetValue);
6234 S.Diag(FL->getExprLoc(), diag::warn_impcast_literal_float_to_integer)
6235 << FL->getType() << T.getUnqualifiedType() << PrettySourceValue
6236 << PrettyTargetValue << FL->getSourceRange() << SourceRange(CContext);
6239 std::string PrettyPrintInRange(const llvm::APSInt &Value, IntRange Range) {
6240 if (!Range.Width) return "0";
6242 llvm::APSInt ValueInRange = Value;
6243 ValueInRange.setIsSigned(!Range.NonNegative);
6244 ValueInRange = ValueInRange.trunc(Range.Width);
6245 return ValueInRange.toString(10);
6248 static bool IsImplicitBoolFloatConversion(Sema &S, Expr *Ex, bool ToBool) {
6249 if (!isa<ImplicitCastExpr>(Ex))
6252 Expr *InnerE = Ex->IgnoreParenImpCasts();
6253 const Type *Target = S.Context.getCanonicalType(Ex->getType()).getTypePtr();
6254 const Type *Source =
6255 S.Context.getCanonicalType(InnerE->getType()).getTypePtr();
6256 if (Target->isDependentType())
6259 const BuiltinType *FloatCandidateBT =
6260 dyn_cast<BuiltinType>(ToBool ? Source : Target);
6261 const Type *BoolCandidateType = ToBool ? Target : Source;
6263 return (BoolCandidateType->isSpecificBuiltinType(BuiltinType::Bool) &&
6264 FloatCandidateBT && (FloatCandidateBT->isFloatingPoint()));
6267 void CheckImplicitArgumentConversions(Sema &S, CallExpr *TheCall,
6268 SourceLocation CC) {
6269 unsigned NumArgs = TheCall->getNumArgs();
6270 for (unsigned i = 0; i < NumArgs; ++i) {
6271 Expr *CurrA = TheCall->getArg(i);
6272 if (!IsImplicitBoolFloatConversion(S, CurrA, true))
6275 bool IsSwapped = ((i > 0) &&
6276 IsImplicitBoolFloatConversion(S, TheCall->getArg(i - 1), false));
6277 IsSwapped |= ((i < (NumArgs - 1)) &&
6278 IsImplicitBoolFloatConversion(S, TheCall->getArg(i + 1), false));
6280 // Warn on this floating-point to bool conversion.
6281 DiagnoseImpCast(S, CurrA->IgnoreParenImpCasts(),
6282 CurrA->getType(), CC,
6283 diag::warn_impcast_floating_point_to_bool);
6288 static void DiagnoseNullConversion(Sema &S, Expr *E, QualType T,
6289 SourceLocation CC) {
6290 if (S.Diags.isIgnored(diag::warn_impcast_null_pointer_to_integer,
6294 // Check for NULL (GNUNull) or nullptr (CXX11_nullptr).
6295 const Expr::NullPointerConstantKind NullKind =
6296 E->isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull);
6297 if (NullKind != Expr::NPCK_GNUNull && NullKind != Expr::NPCK_CXX11_nullptr)
6300 // Return if target type is a safe conversion.
6301 if (T->isAnyPointerType() || T->isBlockPointerType() ||
6302 T->isMemberPointerType() || !T->isScalarType() || T->isNullPtrType())
6305 SourceLocation Loc = E->getSourceRange().getBegin();
6307 // __null is usually wrapped in a macro. Go up a macro if that is the case.
6308 if (NullKind == Expr::NPCK_GNUNull) {
6309 if (Loc.isMacroID())
6310 Loc = S.SourceMgr.getImmediateExpansionRange(Loc).first;
6313 // Only warn if the null and context location are in the same macro expansion.
6314 if (S.SourceMgr.getFileID(Loc) != S.SourceMgr.getFileID(CC))
6317 S.Diag(Loc, diag::warn_impcast_null_pointer_to_integer)
6318 << (NullKind == Expr::NPCK_CXX11_nullptr) << T << clang::SourceRange(CC)
6319 << FixItHint::CreateReplacement(Loc,
6320 S.getFixItZeroLiteralForType(T, Loc));
6323 void CheckImplicitConversion(Sema &S, Expr *E, QualType T,
6324 SourceLocation CC, bool *ICContext = nullptr) {
6325 if (E->isTypeDependent() || E->isValueDependent()) return;
6327 const Type *Source = S.Context.getCanonicalType(E->getType()).getTypePtr();
6328 const Type *Target = S.Context.getCanonicalType(T).getTypePtr();
6329 if (Source == Target) return;
6330 if (Target->isDependentType()) return;
6332 // If the conversion context location is invalid don't complain. We also
6333 // don't want to emit a warning if the issue occurs from the expansion of
6334 // a system macro. The problem is that 'getSpellingLoc()' is slow, so we
6335 // delay this check as long as possible. Once we detect we are in that
6336 // scenario, we just return.
6340 // Diagnose implicit casts to bool.
6341 if (Target->isSpecificBuiltinType(BuiltinType::Bool)) {
6342 if (isa<StringLiteral>(E))
6343 // Warn on string literal to bool. Checks for string literals in logical
6344 // and expressions, for instance, assert(0 && "error here"), are
6345 // prevented by a check in AnalyzeImplicitConversions().
6346 return DiagnoseImpCast(S, E, T, CC,
6347 diag::warn_impcast_string_literal_to_bool);
6348 if (isa<ObjCStringLiteral>(E) || isa<ObjCArrayLiteral>(E) ||
6349 isa<ObjCDictionaryLiteral>(E) || isa<ObjCBoxedExpr>(E)) {
6350 // This covers the literal expressions that evaluate to Objective-C
6352 return DiagnoseImpCast(S, E, T, CC,
6353 diag::warn_impcast_objective_c_literal_to_bool);
6355 if (Source->isPointerType() || Source->canDecayToPointerType()) {
6356 // Warn on pointer to bool conversion that is always true.
6357 S.DiagnoseAlwaysNonNullPointer(E, Expr::NPCK_NotNull, /*IsEqual*/ false,
6362 // Strip vector types.
6363 if (isa<VectorType>(Source)) {
6364 if (!isa<VectorType>(Target)) {
6365 if (S.SourceMgr.isInSystemMacro(CC))
6367 return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_vector_scalar);
6370 // If the vector cast is cast between two vectors of the same size, it is
6371 // a bitcast, not a conversion.
6372 if (S.Context.getTypeSize(Source) == S.Context.getTypeSize(Target))
6375 Source = cast<VectorType>(Source)->getElementType().getTypePtr();
6376 Target = cast<VectorType>(Target)->getElementType().getTypePtr();
6378 if (auto VecTy = dyn_cast<VectorType>(Target))
6379 Target = VecTy->getElementType().getTypePtr();
6381 // Strip complex types.
6382 if (isa<ComplexType>(Source)) {
6383 if (!isa<ComplexType>(Target)) {
6384 if (S.SourceMgr.isInSystemMacro(CC))
6387 return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_complex_scalar);
6390 Source = cast<ComplexType>(Source)->getElementType().getTypePtr();
6391 Target = cast<ComplexType>(Target)->getElementType().getTypePtr();
6394 const BuiltinType *SourceBT = dyn_cast<BuiltinType>(Source);
6395 const BuiltinType *TargetBT = dyn_cast<BuiltinType>(Target);
6397 // If the source is floating point...
6398 if (SourceBT && SourceBT->isFloatingPoint()) {
6399 // ...and the target is floating point...
6400 if (TargetBT && TargetBT->isFloatingPoint()) {
6401 // ...then warn if we're dropping FP rank.
6403 // Builtin FP kinds are ordered by increasing FP rank.
6404 if (SourceBT->getKind() > TargetBT->getKind()) {
6405 // Don't warn about float constants that are precisely
6406 // representable in the target type.
6407 Expr::EvalResult result;
6408 if (E->EvaluateAsRValue(result, S.Context)) {
6409 // Value might be a float, a float vector, or a float complex.
6410 if (IsSameFloatAfterCast(result.Val,
6411 S.Context.getFloatTypeSemantics(QualType(TargetBT, 0)),
6412 S.Context.getFloatTypeSemantics(QualType(SourceBT, 0))))
6416 if (S.SourceMgr.isInSystemMacro(CC))
6419 DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_float_precision);
6424 // If the target is integral, always warn.
6425 if (TargetBT && TargetBT->isInteger()) {
6426 if (S.SourceMgr.isInSystemMacro(CC))
6429 Expr *InnerE = E->IgnoreParenImpCasts();
6430 // We also want to warn on, e.g., "int i = -1.234"
6431 if (UnaryOperator *UOp = dyn_cast<UnaryOperator>(InnerE))
6432 if (UOp->getOpcode() == UO_Minus || UOp->getOpcode() == UO_Plus)
6433 InnerE = UOp->getSubExpr()->IgnoreParenImpCasts();
6435 if (FloatingLiteral *FL = dyn_cast<FloatingLiteral>(InnerE)) {
6436 DiagnoseFloatingLiteralImpCast(S, FL, T, CC);
6438 DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_float_integer);
6442 // If the target is bool, warn if expr is a function or method call.
6443 if (Target->isSpecificBuiltinType(BuiltinType::Bool) &&
6445 // Check last argument of function call to see if it is an
6446 // implicit cast from a type matching the type the result
6447 // is being cast to.
6448 CallExpr *CEx = cast<CallExpr>(E);
6449 unsigned NumArgs = CEx->getNumArgs();
6451 Expr *LastA = CEx->getArg(NumArgs - 1);
6452 Expr *InnerE = LastA->IgnoreParenImpCasts();
6453 const Type *InnerType =
6454 S.Context.getCanonicalType(InnerE->getType()).getTypePtr();
6455 if (isa<ImplicitCastExpr>(LastA) && (InnerType == Target)) {
6456 // Warn on this floating-point to bool conversion
6457 DiagnoseImpCast(S, E, T, CC,
6458 diag::warn_impcast_floating_point_to_bool);
6465 DiagnoseNullConversion(S, E, T, CC);
6467 if (!Source->isIntegerType() || !Target->isIntegerType())
6470 // TODO: remove this early return once the false positives for constant->bool
6471 // in templates, macros, etc, are reduced or removed.
6472 if (Target->isSpecificBuiltinType(BuiltinType::Bool))
6475 IntRange SourceRange = GetExprRange(S.Context, E);
6476 IntRange TargetRange = IntRange::forTargetOfCanonicalType(S.Context, Target);
6478 if (SourceRange.Width > TargetRange.Width) {
6479 // If the source is a constant, use a default-on diagnostic.
6480 // TODO: this should happen for bitfield stores, too.
6481 llvm::APSInt Value(32);
6482 if (E->isIntegerConstantExpr(Value, S.Context)) {
6483 if (S.SourceMgr.isInSystemMacro(CC))
6486 std::string PrettySourceValue = Value.toString(10);
6487 std::string PrettyTargetValue = PrettyPrintInRange(Value, TargetRange);
6489 S.DiagRuntimeBehavior(E->getExprLoc(), E,
6490 S.PDiag(diag::warn_impcast_integer_precision_constant)
6491 << PrettySourceValue << PrettyTargetValue
6492 << E->getType() << T << E->getSourceRange()
6493 << clang::SourceRange(CC));
6497 // People want to build with -Wshorten-64-to-32 and not -Wconversion.
6498 if (S.SourceMgr.isInSystemMacro(CC))
6501 if (TargetRange.Width == 32 && S.Context.getIntWidth(E->getType()) == 64)
6502 return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_integer_64_32,
6503 /* pruneControlFlow */ true);
6504 return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_integer_precision);
6507 if ((TargetRange.NonNegative && !SourceRange.NonNegative) ||
6508 (!TargetRange.NonNegative && SourceRange.NonNegative &&
6509 SourceRange.Width == TargetRange.Width)) {
6511 if (S.SourceMgr.isInSystemMacro(CC))
6514 unsigned DiagID = diag::warn_impcast_integer_sign;
6516 // Traditionally, gcc has warned about this under -Wsign-compare.
6517 // We also want to warn about it in -Wconversion.
6518 // So if -Wconversion is off, use a completely identical diagnostic
6519 // in the sign-compare group.
6520 // The conditional-checking code will
6522 DiagID = diag::warn_impcast_integer_sign_conditional;
6526 return DiagnoseImpCast(S, E, T, CC, DiagID);
6529 // Diagnose conversions between different enumeration types.
6530 // In C, we pretend that the type of an EnumConstantDecl is its enumeration
6531 // type, to give us better diagnostics.
6532 QualType SourceType = E->getType();
6533 if (!S.getLangOpts().CPlusPlus) {
6534 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
6535 if (EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(DRE->getDecl())) {
6536 EnumDecl *Enum = cast<EnumDecl>(ECD->getDeclContext());
6537 SourceType = S.Context.getTypeDeclType(Enum);
6538 Source = S.Context.getCanonicalType(SourceType).getTypePtr();
6542 if (const EnumType *SourceEnum = Source->getAs<EnumType>())
6543 if (const EnumType *TargetEnum = Target->getAs<EnumType>())
6544 if (SourceEnum->getDecl()->hasNameForLinkage() &&
6545 TargetEnum->getDecl()->hasNameForLinkage() &&
6546 SourceEnum != TargetEnum) {
6547 if (S.SourceMgr.isInSystemMacro(CC))
6550 return DiagnoseImpCast(S, E, SourceType, T, CC,
6551 diag::warn_impcast_different_enum_types);
6557 void CheckConditionalOperator(Sema &S, ConditionalOperator *E,
6558 SourceLocation CC, QualType T);
6560 void CheckConditionalOperand(Sema &S, Expr *E, QualType T,
6561 SourceLocation CC, bool &ICContext) {
6562 E = E->IgnoreParenImpCasts();
6564 if (isa<ConditionalOperator>(E))
6565 return CheckConditionalOperator(S, cast<ConditionalOperator>(E), CC, T);
6567 AnalyzeImplicitConversions(S, E, CC);
6568 if (E->getType() != T)
6569 return CheckImplicitConversion(S, E, T, CC, &ICContext);
6573 void CheckConditionalOperator(Sema &S, ConditionalOperator *E,
6574 SourceLocation CC, QualType T) {
6575 AnalyzeImplicitConversions(S, E->getCond(), E->getQuestionLoc());
6577 bool Suspicious = false;
6578 CheckConditionalOperand(S, E->getTrueExpr(), T, CC, Suspicious);
6579 CheckConditionalOperand(S, E->getFalseExpr(), T, CC, Suspicious);
6581 // If -Wconversion would have warned about either of the candidates
6582 // for a signedness conversion to the context type...
6583 if (!Suspicious) return;
6585 // ...but it's currently ignored...
6586 if (!S.Diags.isIgnored(diag::warn_impcast_integer_sign_conditional, CC))
6589 // ...then check whether it would have warned about either of the
6590 // candidates for a signedness conversion to the condition type.
6591 if (E->getType() == T) return;
6594 CheckImplicitConversion(S, E->getTrueExpr()->IgnoreParenImpCasts(),
6595 E->getType(), CC, &Suspicious);
6597 CheckImplicitConversion(S, E->getFalseExpr()->IgnoreParenImpCasts(),
6598 E->getType(), CC, &Suspicious);
6601 /// CheckBoolLikeConversion - Check conversion of given expression to boolean.
6602 /// Input argument E is a logical expression.
6603 static void CheckBoolLikeConversion(Sema &S, Expr *E, SourceLocation CC) {
6604 if (S.getLangOpts().Bool)
6606 CheckImplicitConversion(S, E->IgnoreParenImpCasts(), S.Context.BoolTy, CC);
6609 /// AnalyzeImplicitConversions - Find and report any interesting
6610 /// implicit conversions in the given expression. There are a couple
6611 /// of competing diagnostics here, -Wconversion and -Wsign-compare.
6612 void AnalyzeImplicitConversions(Sema &S, Expr *OrigE, SourceLocation CC) {
6613 QualType T = OrigE->getType();
6614 Expr *E = OrigE->IgnoreParenImpCasts();
6616 if (E->isTypeDependent() || E->isValueDependent())
6619 // For conditional operators, we analyze the arguments as if they
6620 // were being fed directly into the output.
6621 if (isa<ConditionalOperator>(E)) {
6622 ConditionalOperator *CO = cast<ConditionalOperator>(E);
6623 CheckConditionalOperator(S, CO, CC, T);
6627 // Check implicit argument conversions for function calls.
6628 if (CallExpr *Call = dyn_cast<CallExpr>(E))
6629 CheckImplicitArgumentConversions(S, Call, CC);
6631 // Go ahead and check any implicit conversions we might have skipped.
6632 // The non-canonical typecheck is just an optimization;
6633 // CheckImplicitConversion will filter out dead implicit conversions.
6634 if (E->getType() != T)
6635 CheckImplicitConversion(S, E, T, CC);
6637 // Now continue drilling into this expression.
6639 if (PseudoObjectExpr * POE = dyn_cast<PseudoObjectExpr>(E)) {
6640 if (POE->getResultExpr())
6641 E = POE->getResultExpr();
6644 if (const OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E))
6645 return AnalyzeImplicitConversions(S, OVE->getSourceExpr(), CC);
6647 // Skip past explicit casts.
6648 if (isa<ExplicitCastExpr>(E)) {
6649 E = cast<ExplicitCastExpr>(E)->getSubExpr()->IgnoreParenImpCasts();
6650 return AnalyzeImplicitConversions(S, E, CC);
6653 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
6654 // Do a somewhat different check with comparison operators.
6655 if (BO->isComparisonOp())
6656 return AnalyzeComparison(S, BO);
6658 // And with simple assignments.
6659 if (BO->getOpcode() == BO_Assign)
6660 return AnalyzeAssignment(S, BO);
6663 // These break the otherwise-useful invariant below. Fortunately,
6664 // we don't really need to recurse into them, because any internal
6665 // expressions should have been analyzed already when they were
6666 // built into statements.
6667 if (isa<StmtExpr>(E)) return;
6669 // Don't descend into unevaluated contexts.
6670 if (isa<UnaryExprOrTypeTraitExpr>(E)) return;
6672 // Now just recurse over the expression's children.
6673 CC = E->getExprLoc();
6674 BinaryOperator *BO = dyn_cast<BinaryOperator>(E);
6675 bool IsLogicalAndOperator = BO && BO->getOpcode() == BO_LAnd;
6676 for (Stmt::child_range I = E->children(); I; ++I) {
6677 Expr *ChildExpr = dyn_cast_or_null<Expr>(*I);
6681 if (IsLogicalAndOperator &&
6682 isa<StringLiteral>(ChildExpr->IgnoreParenImpCasts()))
6683 // Ignore checking string literals that are in logical and operators.
6684 // This is a common pattern for asserts.
6686 AnalyzeImplicitConversions(S, ChildExpr, CC);
6689 if (BO && BO->isLogicalOp()) {
6690 Expr *SubExpr = BO->getLHS()->IgnoreParenImpCasts();
6691 if (!IsLogicalAndOperator || !isa<StringLiteral>(SubExpr))
6692 ::CheckBoolLikeConversion(S, SubExpr, BO->getExprLoc());
6694 SubExpr = BO->getRHS()->IgnoreParenImpCasts();
6695 if (!IsLogicalAndOperator || !isa<StringLiteral>(SubExpr))
6696 ::CheckBoolLikeConversion(S, SubExpr, BO->getExprLoc());
6699 if (const UnaryOperator *U = dyn_cast<UnaryOperator>(E))
6700 if (U->getOpcode() == UO_LNot)
6701 ::CheckBoolLikeConversion(S, U->getSubExpr(), CC);
6704 } // end anonymous namespace
6712 // Helper function for Sema::DiagnoseAlwaysNonNullPointer.
6713 // Returns true when emitting a warning about taking the address of a reference.
6714 static bool CheckForReference(Sema &SemaRef, const Expr *E,
6715 PartialDiagnostic PD) {
6716 E = E->IgnoreParenImpCasts();
6718 const FunctionDecl *FD = nullptr;
6720 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
6721 if (!DRE->getDecl()->getType()->isReferenceType())
6723 } else if (const MemberExpr *M = dyn_cast<MemberExpr>(E)) {
6724 if (!M->getMemberDecl()->getType()->isReferenceType())
6726 } else if (const CallExpr *Call = dyn_cast<CallExpr>(E)) {
6727 if (!Call->getCallReturnType()->isReferenceType())
6729 FD = Call->getDirectCallee();
6734 SemaRef.Diag(E->getExprLoc(), PD);
6736 // If possible, point to location of function.
6738 SemaRef.Diag(FD->getLocation(), diag::note_reference_is_return_value) << FD;
6744 // Returns true if the SourceLocation is expanded from any macro body.
6745 // Returns false if the SourceLocation is invalid, is from not in a macro
6746 // expansion, or is from expanded from a top-level macro argument.
6747 static bool IsInAnyMacroBody(const SourceManager &SM, SourceLocation Loc) {
6748 if (Loc.isInvalid())
6751 while (Loc.isMacroID()) {
6752 if (SM.isMacroBodyExpansion(Loc))
6754 Loc = SM.getImmediateMacroCallerLoc(Loc);
6760 /// \brief Diagnose pointers that are always non-null.
6761 /// \param E the expression containing the pointer
6762 /// \param NullKind NPCK_NotNull if E is a cast to bool, otherwise, E is
6763 /// compared to a null pointer
6764 /// \param IsEqual True when the comparison is equal to a null pointer
6765 /// \param Range Extra SourceRange to highlight in the diagnostic
6766 void Sema::DiagnoseAlwaysNonNullPointer(Expr *E,
6767 Expr::NullPointerConstantKind NullKind,
6768 bool IsEqual, SourceRange Range) {
6772 // Don't warn inside macros.
6773 if (E->getExprLoc().isMacroID()) {
6774 const SourceManager &SM = getSourceManager();
6775 if (IsInAnyMacroBody(SM, E->getExprLoc()) ||
6776 IsInAnyMacroBody(SM, Range.getBegin()))
6779 E = E->IgnoreImpCasts();
6781 const bool IsCompare = NullKind != Expr::NPCK_NotNull;
6783 if (isa<CXXThisExpr>(E)) {
6784 unsigned DiagID = IsCompare ? diag::warn_this_null_compare
6785 : diag::warn_this_bool_conversion;
6786 Diag(E->getExprLoc(), DiagID) << E->getSourceRange() << Range << IsEqual;
6790 bool IsAddressOf = false;
6792 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
6793 if (UO->getOpcode() != UO_AddrOf)
6796 E = UO->getSubExpr();
6800 unsigned DiagID = IsCompare
6801 ? diag::warn_address_of_reference_null_compare
6802 : diag::warn_address_of_reference_bool_conversion;
6803 PartialDiagnostic PD = PDiag(DiagID) << E->getSourceRange() << Range
6805 if (CheckForReference(*this, E, PD)) {
6810 // Expect to find a single Decl. Skip anything more complicated.
6811 ValueDecl *D = nullptr;
6812 if (DeclRefExpr *R = dyn_cast<DeclRefExpr>(E)) {
6814 } else if (MemberExpr *M = dyn_cast<MemberExpr>(E)) {
6815 D = M->getMemberDecl();
6818 // Weak Decls can be null.
6819 if (!D || D->isWeak())
6822 // Check for parameter decl with nonnull attribute
6823 if (const ParmVarDecl* PV = dyn_cast<ParmVarDecl>(D)) {
6824 if (getCurFunction() && !getCurFunction()->ModifiedNonNullParams.count(PV))
6825 if (const FunctionDecl* FD = dyn_cast<FunctionDecl>(PV->getDeclContext())) {
6826 unsigned NumArgs = FD->getNumParams();
6827 llvm::SmallBitVector AttrNonNull(NumArgs);
6828 for (const auto *NonNull : FD->specific_attrs<NonNullAttr>()) {
6829 if (!NonNull->args_size()) {
6830 AttrNonNull.set(0, NumArgs);
6833 for (unsigned Val : NonNull->args()) {
6836 AttrNonNull.set(Val);
6839 if (!AttrNonNull.empty())
6840 for (unsigned i = 0; i < NumArgs; ++i)
6841 if (FD->getParamDecl(i) == PV &&
6842 (AttrNonNull[i] || PV->hasAttr<NonNullAttr>())) {
6844 llvm::raw_string_ostream S(Str);
6845 E->printPretty(S, nullptr, getPrintingPolicy());
6846 unsigned DiagID = IsCompare ? diag::warn_nonnull_parameter_compare
6847 : diag::warn_cast_nonnull_to_bool;
6848 Diag(E->getExprLoc(), DiagID) << S.str() << E->getSourceRange()
6849 << Range << IsEqual;
6855 QualType T = D->getType();
6856 const bool IsArray = T->isArrayType();
6857 const bool IsFunction = T->isFunctionType();
6859 // Address of function is used to silence the function warning.
6860 if (IsAddressOf && IsFunction) {
6865 if (!IsAddressOf && !IsFunction && !IsArray)
6868 // Pretty print the expression for the diagnostic.
6870 llvm::raw_string_ostream S(Str);
6871 E->printPretty(S, nullptr, getPrintingPolicy());
6873 unsigned DiagID = IsCompare ? diag::warn_null_pointer_compare
6874 : diag::warn_impcast_pointer_to_bool;
6877 DiagType = AddressOf;
6878 else if (IsFunction)
6879 DiagType = FunctionPointer;
6881 DiagType = ArrayPointer;
6883 llvm_unreachable("Could not determine diagnostic.");
6884 Diag(E->getExprLoc(), DiagID) << DiagType << S.str() << E->getSourceRange()
6885 << Range << IsEqual;
6890 // Suggest '&' to silence the function warning.
6891 Diag(E->getExprLoc(), diag::note_function_warning_silence)
6892 << FixItHint::CreateInsertion(E->getLocStart(), "&");
6894 // Check to see if '()' fixit should be emitted.
6895 QualType ReturnType;
6896 UnresolvedSet<4> NonTemplateOverloads;
6897 tryExprAsCall(*E, ReturnType, NonTemplateOverloads);
6898 if (ReturnType.isNull())
6902 // There are two cases here. If there is null constant, the only suggest
6903 // for a pointer return type. If the null is 0, then suggest if the return
6904 // type is a pointer or an integer type.
6905 if (!ReturnType->isPointerType()) {
6906 if (NullKind == Expr::NPCK_ZeroExpression ||
6907 NullKind == Expr::NPCK_ZeroLiteral) {
6908 if (!ReturnType->isIntegerType())
6914 } else { // !IsCompare
6915 // For function to bool, only suggest if the function pointer has bool
6917 if (!ReturnType->isSpecificBuiltinType(BuiltinType::Bool))
6920 Diag(E->getExprLoc(), diag::note_function_to_function_call)
6921 << FixItHint::CreateInsertion(getLocForEndOfToken(E->getLocEnd()), "()");
6925 /// Diagnoses "dangerous" implicit conversions within the given
6926 /// expression (which is a full expression). Implements -Wconversion
6927 /// and -Wsign-compare.
6929 /// \param CC the "context" location of the implicit conversion, i.e.
6930 /// the most location of the syntactic entity requiring the implicit
6932 void Sema::CheckImplicitConversions(Expr *E, SourceLocation CC) {
6933 // Don't diagnose in unevaluated contexts.
6934 if (isUnevaluatedContext())
6937 // Don't diagnose for value- or type-dependent expressions.
6938 if (E->isTypeDependent() || E->isValueDependent())
6941 // Check for array bounds violations in cases where the check isn't triggered
6942 // elsewhere for other Expr types (like BinaryOperators), e.g. when an
6943 // ArraySubscriptExpr is on the RHS of a variable initialization.
6944 CheckArrayAccess(E);
6946 // This is not the right CC for (e.g.) a variable initialization.
6947 AnalyzeImplicitConversions(*this, E, CC);
6950 /// CheckBoolLikeConversion - Check conversion of given expression to boolean.
6951 /// Input argument E is a logical expression.
6952 void Sema::CheckBoolLikeConversion(Expr *E, SourceLocation CC) {
6953 ::CheckBoolLikeConversion(*this, E, CC);
6956 /// Diagnose when expression is an integer constant expression and its evaluation
6957 /// results in integer overflow
6958 void Sema::CheckForIntOverflow (Expr *E) {
6959 if (isa<BinaryOperator>(E->IgnoreParenCasts()))
6960 E->IgnoreParenCasts()->EvaluateForOverflow(Context);
6964 /// \brief Visitor for expressions which looks for unsequenced operations on the
6966 class SequenceChecker : public EvaluatedExprVisitor<SequenceChecker> {
6967 typedef EvaluatedExprVisitor<SequenceChecker> Base;
6969 /// \brief A tree of sequenced regions within an expression. Two regions are
6970 /// unsequenced if one is an ancestor or a descendent of the other. When we
6971 /// finish processing an expression with sequencing, such as a comma
6972 /// expression, we fold its tree nodes into its parent, since they are
6973 /// unsequenced with respect to nodes we will visit later.
6974 class SequenceTree {
6976 explicit Value(unsigned Parent) : Parent(Parent), Merged(false) {}
6977 unsigned Parent : 31;
6980 SmallVector<Value, 8> Values;
6983 /// \brief A region within an expression which may be sequenced with respect
6984 /// to some other region.
6986 explicit Seq(unsigned N) : Index(N) {}
6988 friend class SequenceTree;
6993 SequenceTree() { Values.push_back(Value(0)); }
6994 Seq root() const { return Seq(0); }
6996 /// \brief Create a new sequence of operations, which is an unsequenced
6997 /// subset of \p Parent. This sequence of operations is sequenced with
6998 /// respect to other children of \p Parent.
6999 Seq allocate(Seq Parent) {
7000 Values.push_back(Value(Parent.Index));
7001 return Seq(Values.size() - 1);
7004 /// \brief Merge a sequence of operations into its parent.
7006 Values[S.Index].Merged = true;
7009 /// \brief Determine whether two operations are unsequenced. This operation
7010 /// is asymmetric: \p Cur should be the more recent sequence, and \p Old
7011 /// should have been merged into its parent as appropriate.
7012 bool isUnsequenced(Seq Cur, Seq Old) {
7013 unsigned C = representative(Cur.Index);
7014 unsigned Target = representative(Old.Index);
7015 while (C >= Target) {
7018 C = Values[C].Parent;
7024 /// \brief Pick a representative for a sequence.
7025 unsigned representative(unsigned K) {
7026 if (Values[K].Merged)
7027 // Perform path compression as we go.
7028 return Values[K].Parent = representative(Values[K].Parent);
7033 /// An object for which we can track unsequenced uses.
7034 typedef NamedDecl *Object;
7036 /// Different flavors of object usage which we track. We only track the
7037 /// least-sequenced usage of each kind.
7039 /// A read of an object. Multiple unsequenced reads are OK.
7041 /// A modification of an object which is sequenced before the value
7042 /// computation of the expression, such as ++n in C++.
7044 /// A modification of an object which is not sequenced before the value
7045 /// computation of the expression, such as n++.
7048 UK_Count = UK_ModAsSideEffect + 1
7052 Usage() : Use(nullptr), Seq() {}
7054 SequenceTree::Seq Seq;
7058 UsageInfo() : Diagnosed(false) {}
7059 Usage Uses[UK_Count];
7060 /// Have we issued a diagnostic for this variable already?
7063 typedef llvm::SmallDenseMap<Object, UsageInfo, 16> UsageInfoMap;
7066 /// Sequenced regions within the expression.
7068 /// Declaration modifications and references which we have seen.
7069 UsageInfoMap UsageMap;
7070 /// The region we are currently within.
7071 SequenceTree::Seq Region;
7072 /// Filled in with declarations which were modified as a side-effect
7073 /// (that is, post-increment operations).
7074 SmallVectorImpl<std::pair<Object, Usage> > *ModAsSideEffect;
7075 /// Expressions to check later. We defer checking these to reduce
7077 SmallVectorImpl<Expr *> &WorkList;
7079 /// RAII object wrapping the visitation of a sequenced subexpression of an
7080 /// expression. At the end of this process, the side-effects of the evaluation
7081 /// become sequenced with respect to the value computation of the result, so
7082 /// we downgrade any UK_ModAsSideEffect within the evaluation to
7084 struct SequencedSubexpression {
7085 SequencedSubexpression(SequenceChecker &Self)
7086 : Self(Self), OldModAsSideEffect(Self.ModAsSideEffect) {
7087 Self.ModAsSideEffect = &ModAsSideEffect;
7089 ~SequencedSubexpression() {
7090 for (auto MI = ModAsSideEffect.rbegin(), ME = ModAsSideEffect.rend();
7092 UsageInfo &U = Self.UsageMap[MI->first];
7093 auto &SideEffectUsage = U.Uses[UK_ModAsSideEffect];
7094 Self.addUsage(U, MI->first, SideEffectUsage.Use, UK_ModAsValue);
7095 SideEffectUsage = MI->second;
7097 Self.ModAsSideEffect = OldModAsSideEffect;
7100 SequenceChecker &Self;
7101 SmallVector<std::pair<Object, Usage>, 4> ModAsSideEffect;
7102 SmallVectorImpl<std::pair<Object, Usage> > *OldModAsSideEffect;
7105 /// RAII object wrapping the visitation of a subexpression which we might
7106 /// choose to evaluate as a constant. If any subexpression is evaluated and
7107 /// found to be non-constant, this allows us to suppress the evaluation of
7108 /// the outer expression.
7109 class EvaluationTracker {
7111 EvaluationTracker(SequenceChecker &Self)
7112 : Self(Self), Prev(Self.EvalTracker), EvalOK(true) {
7113 Self.EvalTracker = this;
7115 ~EvaluationTracker() {
7116 Self.EvalTracker = Prev;
7118 Prev->EvalOK &= EvalOK;
7121 bool evaluate(const Expr *E, bool &Result) {
7122 if (!EvalOK || E->isValueDependent())
7124 EvalOK = E->EvaluateAsBooleanCondition(Result, Self.SemaRef.Context);
7129 SequenceChecker &Self;
7130 EvaluationTracker *Prev;
7134 /// \brief Find the object which is produced by the specified expression,
7136 Object getObject(Expr *E, bool Mod) const {
7137 E = E->IgnoreParenCasts();
7138 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
7139 if (Mod && (UO->getOpcode() == UO_PreInc || UO->getOpcode() == UO_PreDec))
7140 return getObject(UO->getSubExpr(), Mod);
7141 } else if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
7142 if (BO->getOpcode() == BO_Comma)
7143 return getObject(BO->getRHS(), Mod);
7144 if (Mod && BO->isAssignmentOp())
7145 return getObject(BO->getLHS(), Mod);
7146 } else if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
7147 // FIXME: Check for more interesting cases, like "x.n = ++x.n".
7148 if (isa<CXXThisExpr>(ME->getBase()->IgnoreParenCasts()))
7149 return ME->getMemberDecl();
7150 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
7151 // FIXME: If this is a reference, map through to its value.
7152 return DRE->getDecl();
7156 /// \brief Note that an object was modified or used by an expression.
7157 void addUsage(UsageInfo &UI, Object O, Expr *Ref, UsageKind UK) {
7158 Usage &U = UI.Uses[UK];
7159 if (!U.Use || !Tree.isUnsequenced(Region, U.Seq)) {
7160 if (UK == UK_ModAsSideEffect && ModAsSideEffect)
7161 ModAsSideEffect->push_back(std::make_pair(O, U));
7166 /// \brief Check whether a modification or use conflicts with a prior usage.
7167 void checkUsage(Object O, UsageInfo &UI, Expr *Ref, UsageKind OtherKind,
7172 const Usage &U = UI.Uses[OtherKind];
7173 if (!U.Use || !Tree.isUnsequenced(Region, U.Seq))
7177 Expr *ModOrUse = Ref;
7178 if (OtherKind == UK_Use)
7179 std::swap(Mod, ModOrUse);
7181 SemaRef.Diag(Mod->getExprLoc(),
7182 IsModMod ? diag::warn_unsequenced_mod_mod
7183 : diag::warn_unsequenced_mod_use)
7184 << O << SourceRange(ModOrUse->getExprLoc());
7185 UI.Diagnosed = true;
7188 void notePreUse(Object O, Expr *Use) {
7189 UsageInfo &U = UsageMap[O];
7190 // Uses conflict with other modifications.
7191 checkUsage(O, U, Use, UK_ModAsValue, false);
7193 void notePostUse(Object O, Expr *Use) {
7194 UsageInfo &U = UsageMap[O];
7195 checkUsage(O, U, Use, UK_ModAsSideEffect, false);
7196 addUsage(U, O, Use, UK_Use);
7199 void notePreMod(Object O, Expr *Mod) {
7200 UsageInfo &U = UsageMap[O];
7201 // Modifications conflict with other modifications and with uses.
7202 checkUsage(O, U, Mod, UK_ModAsValue, true);
7203 checkUsage(O, U, Mod, UK_Use, false);
7205 void notePostMod(Object O, Expr *Use, UsageKind UK) {
7206 UsageInfo &U = UsageMap[O];
7207 checkUsage(O, U, Use, UK_ModAsSideEffect, true);
7208 addUsage(U, O, Use, UK);
7212 SequenceChecker(Sema &S, Expr *E, SmallVectorImpl<Expr *> &WorkList)
7213 : Base(S.Context), SemaRef(S), Region(Tree.root()),
7214 ModAsSideEffect(nullptr), WorkList(WorkList), EvalTracker(nullptr) {
7218 void VisitStmt(Stmt *S) {
7219 // Skip all statements which aren't expressions for now.
7222 void VisitExpr(Expr *E) {
7223 // By default, just recurse to evaluated subexpressions.
7227 void VisitCastExpr(CastExpr *E) {
7228 Object O = Object();
7229 if (E->getCastKind() == CK_LValueToRValue)
7230 O = getObject(E->getSubExpr(), false);
7239 void VisitBinComma(BinaryOperator *BO) {
7240 // C++11 [expr.comma]p1:
7241 // Every value computation and side effect associated with the left
7242 // expression is sequenced before every value computation and side
7243 // effect associated with the right expression.
7244 SequenceTree::Seq LHS = Tree.allocate(Region);
7245 SequenceTree::Seq RHS = Tree.allocate(Region);
7246 SequenceTree::Seq OldRegion = Region;
7249 SequencedSubexpression SeqLHS(*this);
7251 Visit(BO->getLHS());
7255 Visit(BO->getRHS());
7259 // Forget that LHS and RHS are sequenced. They are both unsequenced
7260 // with respect to other stuff.
7265 void VisitBinAssign(BinaryOperator *BO) {
7266 // The modification is sequenced after the value computation of the LHS
7267 // and RHS, so check it before inspecting the operands and update the
7269 Object O = getObject(BO->getLHS(), true);
7271 return VisitExpr(BO);
7275 // C++11 [expr.ass]p7:
7276 // E1 op= E2 is equivalent to E1 = E1 op E2, except that E1 is evaluated
7279 // Therefore, for a compound assignment operator, O is considered used
7280 // everywhere except within the evaluation of E1 itself.
7281 if (isa<CompoundAssignOperator>(BO))
7284 Visit(BO->getLHS());
7286 if (isa<CompoundAssignOperator>(BO))
7289 Visit(BO->getRHS());
7291 // C++11 [expr.ass]p1:
7292 // the assignment is sequenced [...] before the value computation of the
7293 // assignment expression.
7294 // C11 6.5.16/3 has no such rule.
7295 notePostMod(O, BO, SemaRef.getLangOpts().CPlusPlus ? UK_ModAsValue
7296 : UK_ModAsSideEffect);
7298 void VisitCompoundAssignOperator(CompoundAssignOperator *CAO) {
7299 VisitBinAssign(CAO);
7302 void VisitUnaryPreInc(UnaryOperator *UO) { VisitUnaryPreIncDec(UO); }
7303 void VisitUnaryPreDec(UnaryOperator *UO) { VisitUnaryPreIncDec(UO); }
7304 void VisitUnaryPreIncDec(UnaryOperator *UO) {
7305 Object O = getObject(UO->getSubExpr(), true);
7307 return VisitExpr(UO);
7310 Visit(UO->getSubExpr());
7311 // C++11 [expr.pre.incr]p1:
7312 // the expression ++x is equivalent to x+=1
7313 notePostMod(O, UO, SemaRef.getLangOpts().CPlusPlus ? UK_ModAsValue
7314 : UK_ModAsSideEffect);
7317 void VisitUnaryPostInc(UnaryOperator *UO) { VisitUnaryPostIncDec(UO); }
7318 void VisitUnaryPostDec(UnaryOperator *UO) { VisitUnaryPostIncDec(UO); }
7319 void VisitUnaryPostIncDec(UnaryOperator *UO) {
7320 Object O = getObject(UO->getSubExpr(), true);
7322 return VisitExpr(UO);
7325 Visit(UO->getSubExpr());
7326 notePostMod(O, UO, UK_ModAsSideEffect);
7329 /// Don't visit the RHS of '&&' or '||' if it might not be evaluated.
7330 void VisitBinLOr(BinaryOperator *BO) {
7331 // The side-effects of the LHS of an '&&' are sequenced before the
7332 // value computation of the RHS, and hence before the value computation
7333 // of the '&&' itself, unless the LHS evaluates to zero. We treat them
7334 // as if they were unconditionally sequenced.
7335 EvaluationTracker Eval(*this);
7337 SequencedSubexpression Sequenced(*this);
7338 Visit(BO->getLHS());
7342 if (Eval.evaluate(BO->getLHS(), Result)) {
7344 Visit(BO->getRHS());
7346 // Check for unsequenced operations in the RHS, treating it as an
7347 // entirely separate evaluation.
7349 // FIXME: If there are operations in the RHS which are unsequenced
7350 // with respect to operations outside the RHS, and those operations
7351 // are unconditionally evaluated, diagnose them.
7352 WorkList.push_back(BO->getRHS());
7355 void VisitBinLAnd(BinaryOperator *BO) {
7356 EvaluationTracker Eval(*this);
7358 SequencedSubexpression Sequenced(*this);
7359 Visit(BO->getLHS());
7363 if (Eval.evaluate(BO->getLHS(), Result)) {
7365 Visit(BO->getRHS());
7367 WorkList.push_back(BO->getRHS());
7371 // Only visit the condition, unless we can be sure which subexpression will
7373 void VisitAbstractConditionalOperator(AbstractConditionalOperator *CO) {
7374 EvaluationTracker Eval(*this);
7376 SequencedSubexpression Sequenced(*this);
7377 Visit(CO->getCond());
7381 if (Eval.evaluate(CO->getCond(), Result))
7382 Visit(Result ? CO->getTrueExpr() : CO->getFalseExpr());
7384 WorkList.push_back(CO->getTrueExpr());
7385 WorkList.push_back(CO->getFalseExpr());
7389 void VisitCallExpr(CallExpr *CE) {
7390 // C++11 [intro.execution]p15:
7391 // When calling a function [...], every value computation and side effect
7392 // associated with any argument expression, or with the postfix expression
7393 // designating the called function, is sequenced before execution of every
7394 // expression or statement in the body of the function [and thus before
7395 // the value computation of its result].
7396 SequencedSubexpression Sequenced(*this);
7397 Base::VisitCallExpr(CE);
7399 // FIXME: CXXNewExpr and CXXDeleteExpr implicitly call functions.
7402 void VisitCXXConstructExpr(CXXConstructExpr *CCE) {
7403 // This is a call, so all subexpressions are sequenced before the result.
7404 SequencedSubexpression Sequenced(*this);
7406 if (!CCE->isListInitialization())
7407 return VisitExpr(CCE);
7409 // In C++11, list initializations are sequenced.
7410 SmallVector<SequenceTree::Seq, 32> Elts;
7411 SequenceTree::Seq Parent = Region;
7412 for (CXXConstructExpr::arg_iterator I = CCE->arg_begin(),
7415 Region = Tree.allocate(Parent);
7416 Elts.push_back(Region);
7420 // Forget that the initializers are sequenced.
7422 for (unsigned I = 0; I < Elts.size(); ++I)
7423 Tree.merge(Elts[I]);
7426 void VisitInitListExpr(InitListExpr *ILE) {
7427 if (!SemaRef.getLangOpts().CPlusPlus11)
7428 return VisitExpr(ILE);
7430 // In C++11, list initializations are sequenced.
7431 SmallVector<SequenceTree::Seq, 32> Elts;
7432 SequenceTree::Seq Parent = Region;
7433 for (unsigned I = 0; I < ILE->getNumInits(); ++I) {
7434 Expr *E = ILE->getInit(I);
7436 Region = Tree.allocate(Parent);
7437 Elts.push_back(Region);
7441 // Forget that the initializers are sequenced.
7443 for (unsigned I = 0; I < Elts.size(); ++I)
7444 Tree.merge(Elts[I]);
7449 void Sema::CheckUnsequencedOperations(Expr *E) {
7450 SmallVector<Expr *, 8> WorkList;
7451 WorkList.push_back(E);
7452 while (!WorkList.empty()) {
7453 Expr *Item = WorkList.pop_back_val();
7454 SequenceChecker(*this, Item, WorkList);
7458 void Sema::CheckCompletedExpr(Expr *E, SourceLocation CheckLoc,
7460 CheckImplicitConversions(E, CheckLoc);
7461 CheckUnsequencedOperations(E);
7462 if (!IsConstexpr && !E->isValueDependent())
7463 CheckForIntOverflow(E);
7466 void Sema::CheckBitFieldInitialization(SourceLocation InitLoc,
7467 FieldDecl *BitField,
7469 (void) AnalyzeBitFieldAssignment(*this, BitField, Init, InitLoc);
7472 /// CheckParmsForFunctionDef - Check that the parameters of the given
7473 /// function are appropriate for the definition of a function. This
7474 /// takes care of any checks that cannot be performed on the
7475 /// declaration itself, e.g., that the types of each of the function
7476 /// parameters are complete.
7477 bool Sema::CheckParmsForFunctionDef(ParmVarDecl *const *P,
7478 ParmVarDecl *const *PEnd,
7479 bool CheckParameterNames) {
7480 bool HasInvalidParm = false;
7481 for (; P != PEnd; ++P) {
7482 ParmVarDecl *Param = *P;
7484 // C99 6.7.5.3p4: the parameters in a parameter type list in a
7485 // function declarator that is part of a function definition of
7486 // that function shall not have incomplete type.
7488 // This is also C++ [dcl.fct]p6.
7489 if (!Param->isInvalidDecl() &&
7490 RequireCompleteType(Param->getLocation(), Param->getType(),
7491 diag::err_typecheck_decl_incomplete_type)) {
7492 Param->setInvalidDecl();
7493 HasInvalidParm = true;
7496 // C99 6.9.1p5: If the declarator includes a parameter type list, the
7497 // declaration of each parameter shall include an identifier.
7498 if (CheckParameterNames &&
7499 Param->getIdentifier() == nullptr &&
7500 !Param->isImplicit() &&
7501 !getLangOpts().CPlusPlus)
7502 Diag(Param->getLocation(), diag::err_parameter_name_omitted);
7505 // If the function declarator is not part of a definition of that
7506 // function, parameters may have incomplete type and may use the [*]
7507 // notation in their sequences of declarator specifiers to specify
7508 // variable length array types.
7509 QualType PType = Param->getOriginalType();
7510 while (const ArrayType *AT = Context.getAsArrayType(PType)) {
7511 if (AT->getSizeModifier() == ArrayType::Star) {
7512 // FIXME: This diagnostic should point the '[*]' if source-location
7513 // information is added for it.
7514 Diag(Param->getLocation(), diag::err_array_star_in_function_definition);
7517 PType= AT->getElementType();
7520 // MSVC destroys objects passed by value in the callee. Therefore a
7521 // function definition which takes such a parameter must be able to call the
7522 // object's destructor. However, we don't perform any direct access check
7524 if (getLangOpts().CPlusPlus && Context.getTargetInfo()
7526 .areArgsDestroyedLeftToRightInCallee()) {
7527 if (!Param->isInvalidDecl()) {
7528 if (const RecordType *RT = Param->getType()->getAs<RecordType>()) {
7529 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
7530 if (!ClassDecl->isInvalidDecl() &&
7531 !ClassDecl->hasIrrelevantDestructor() &&
7532 !ClassDecl->isDependentContext()) {
7533 CXXDestructorDecl *Destructor = LookupDestructor(ClassDecl);
7534 MarkFunctionReferenced(Param->getLocation(), Destructor);
7535 DiagnoseUseOfDecl(Destructor, Param->getLocation());
7542 return HasInvalidParm;
7545 /// CheckCastAlign - Implements -Wcast-align, which warns when a
7546 /// pointer cast increases the alignment requirements.
7547 void Sema::CheckCastAlign(Expr *Op, QualType T, SourceRange TRange) {
7548 // This is actually a lot of work to potentially be doing on every
7549 // cast; don't do it if we're ignoring -Wcast_align (as is the default).
7550 if (getDiagnostics().isIgnored(diag::warn_cast_align, TRange.getBegin()))
7553 // Ignore dependent types.
7554 if (T->isDependentType() || Op->getType()->isDependentType())
7557 // Require that the destination be a pointer type.
7558 const PointerType *DestPtr = T->getAs<PointerType>();
7559 if (!DestPtr) return;
7561 // If the destination has alignment 1, we're done.
7562 QualType DestPointee = DestPtr->getPointeeType();
7563 if (DestPointee->isIncompleteType()) return;
7564 CharUnits DestAlign = Context.getTypeAlignInChars(DestPointee);
7565 if (DestAlign.isOne()) return;
7567 // Require that the source be a pointer type.
7568 const PointerType *SrcPtr = Op->getType()->getAs<PointerType>();
7569 if (!SrcPtr) return;
7570 QualType SrcPointee = SrcPtr->getPointeeType();
7572 // Whitelist casts from cv void*. We already implicitly
7573 // whitelisted casts to cv void*, since they have alignment 1.
7574 // Also whitelist casts involving incomplete types, which implicitly
7576 if (SrcPointee->isIncompleteType()) return;
7578 CharUnits SrcAlign = Context.getTypeAlignInChars(SrcPointee);
7579 if (SrcAlign >= DestAlign) return;
7581 Diag(TRange.getBegin(), diag::warn_cast_align)
7582 << Op->getType() << T
7583 << static_cast<unsigned>(SrcAlign.getQuantity())
7584 << static_cast<unsigned>(DestAlign.getQuantity())
7585 << TRange << Op->getSourceRange();
7588 static const Type* getElementType(const Expr *BaseExpr) {
7589 const Type* EltType = BaseExpr->getType().getTypePtr();
7590 if (EltType->isAnyPointerType())
7591 return EltType->getPointeeType().getTypePtr();
7592 else if (EltType->isArrayType())
7593 return EltType->getBaseElementTypeUnsafe();
7597 /// \brief Check whether this array fits the idiom of a size-one tail padded
7598 /// array member of a struct.
7600 /// We avoid emitting out-of-bounds access warnings for such arrays as they are
7601 /// commonly used to emulate flexible arrays in C89 code.
7602 static bool IsTailPaddedMemberArray(Sema &S, llvm::APInt Size,
7603 const NamedDecl *ND) {
7604 if (Size != 1 || !ND) return false;
7606 const FieldDecl *FD = dyn_cast<FieldDecl>(ND);
7607 if (!FD) return false;
7609 // Don't consider sizes resulting from macro expansions or template argument
7610 // substitution to form C89 tail-padded arrays.
7612 TypeSourceInfo *TInfo = FD->getTypeSourceInfo();
7614 TypeLoc TL = TInfo->getTypeLoc();
7615 // Look through typedefs.
7616 if (TypedefTypeLoc TTL = TL.getAs<TypedefTypeLoc>()) {
7617 const TypedefNameDecl *TDL = TTL.getTypedefNameDecl();
7618 TInfo = TDL->getTypeSourceInfo();
7621 if (ConstantArrayTypeLoc CTL = TL.getAs<ConstantArrayTypeLoc>()) {
7622 const Expr *SizeExpr = dyn_cast<IntegerLiteral>(CTL.getSizeExpr());
7623 if (!SizeExpr || SizeExpr->getExprLoc().isMacroID())
7629 const RecordDecl *RD = dyn_cast<RecordDecl>(FD->getDeclContext());
7630 if (!RD) return false;
7631 if (RD->isUnion()) return false;
7632 if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) {
7633 if (!CRD->isStandardLayout()) return false;
7636 // See if this is the last field decl in the record.
7638 while ((D = D->getNextDeclInContext()))
7639 if (isa<FieldDecl>(D))
7644 void Sema::CheckArrayAccess(const Expr *BaseExpr, const Expr *IndexExpr,
7645 const ArraySubscriptExpr *ASE,
7646 bool AllowOnePastEnd, bool IndexNegated) {
7647 IndexExpr = IndexExpr->IgnoreParenImpCasts();
7648 if (IndexExpr->isValueDependent())
7651 const Type *EffectiveType = getElementType(BaseExpr);
7652 BaseExpr = BaseExpr->IgnoreParenCasts();
7653 const ConstantArrayType *ArrayTy =
7654 Context.getAsConstantArrayType(BaseExpr->getType());
7659 if (!IndexExpr->EvaluateAsInt(index, Context))
7664 const NamedDecl *ND = nullptr;
7665 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(BaseExpr))
7666 ND = dyn_cast<NamedDecl>(DRE->getDecl());
7667 if (const MemberExpr *ME = dyn_cast<MemberExpr>(BaseExpr))
7668 ND = dyn_cast<NamedDecl>(ME->getMemberDecl());
7670 if (index.isUnsigned() || !index.isNegative()) {
7671 llvm::APInt size = ArrayTy->getSize();
7672 if (!size.isStrictlyPositive())
7675 const Type* BaseType = getElementType(BaseExpr);
7676 if (BaseType != EffectiveType) {
7677 // Make sure we're comparing apples to apples when comparing index to size
7678 uint64_t ptrarith_typesize = Context.getTypeSize(EffectiveType);
7679 uint64_t array_typesize = Context.getTypeSize(BaseType);
7680 // Handle ptrarith_typesize being zero, such as when casting to void*
7681 if (!ptrarith_typesize) ptrarith_typesize = 1;
7682 if (ptrarith_typesize != array_typesize) {
7683 // There's a cast to a different size type involved
7684 uint64_t ratio = array_typesize / ptrarith_typesize;
7685 // TODO: Be smarter about handling cases where array_typesize is not a
7686 // multiple of ptrarith_typesize
7687 if (ptrarith_typesize * ratio == array_typesize)
7688 size *= llvm::APInt(size.getBitWidth(), ratio);
7692 if (size.getBitWidth() > index.getBitWidth())
7693 index = index.zext(size.getBitWidth());
7694 else if (size.getBitWidth() < index.getBitWidth())
7695 size = size.zext(index.getBitWidth());
7697 // For array subscripting the index must be less than size, but for pointer
7698 // arithmetic also allow the index (offset) to be equal to size since
7699 // computing the next address after the end of the array is legal and
7700 // commonly done e.g. in C++ iterators and range-based for loops.
7701 if (AllowOnePastEnd ? index.ule(size) : index.ult(size))
7704 // Also don't warn for arrays of size 1 which are members of some
7705 // structure. These are often used to approximate flexible arrays in C89
7707 if (IsTailPaddedMemberArray(*this, size, ND))
7710 // Suppress the warning if the subscript expression (as identified by the
7711 // ']' location) and the index expression are both from macro expansions
7712 // within a system header.
7714 SourceLocation RBracketLoc = SourceMgr.getSpellingLoc(
7715 ASE->getRBracketLoc());
7716 if (SourceMgr.isInSystemHeader(RBracketLoc)) {
7717 SourceLocation IndexLoc = SourceMgr.getSpellingLoc(
7718 IndexExpr->getLocStart());
7719 if (SourceMgr.isWrittenInSameFile(RBracketLoc, IndexLoc))
7724 unsigned DiagID = diag::warn_ptr_arith_exceeds_bounds;
7726 DiagID = diag::warn_array_index_exceeds_bounds;
7728 DiagRuntimeBehavior(BaseExpr->getLocStart(), BaseExpr,
7729 PDiag(DiagID) << index.toString(10, true)
7730 << size.toString(10, true)
7731 << (unsigned)size.getLimitedValue(~0U)
7732 << IndexExpr->getSourceRange());
7734 unsigned DiagID = diag::warn_array_index_precedes_bounds;
7736 DiagID = diag::warn_ptr_arith_precedes_bounds;
7737 if (index.isNegative()) index = -index;
7740 DiagRuntimeBehavior(BaseExpr->getLocStart(), BaseExpr,
7741 PDiag(DiagID) << index.toString(10, true)
7742 << IndexExpr->getSourceRange());
7746 // Try harder to find a NamedDecl to point at in the note.
7747 while (const ArraySubscriptExpr *ASE =
7748 dyn_cast<ArraySubscriptExpr>(BaseExpr))
7749 BaseExpr = ASE->getBase()->IgnoreParenCasts();
7750 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(BaseExpr))
7751 ND = dyn_cast<NamedDecl>(DRE->getDecl());
7752 if (const MemberExpr *ME = dyn_cast<MemberExpr>(BaseExpr))
7753 ND = dyn_cast<NamedDecl>(ME->getMemberDecl());
7757 DiagRuntimeBehavior(ND->getLocStart(), BaseExpr,
7758 PDiag(diag::note_array_index_out_of_bounds)
7759 << ND->getDeclName());
7762 void Sema::CheckArrayAccess(const Expr *expr) {
7763 int AllowOnePastEnd = 0;
7765 expr = expr->IgnoreParenImpCasts();
7766 switch (expr->getStmtClass()) {
7767 case Stmt::ArraySubscriptExprClass: {
7768 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(expr);
7769 CheckArrayAccess(ASE->getBase(), ASE->getIdx(), ASE,
7770 AllowOnePastEnd > 0);
7773 case Stmt::UnaryOperatorClass: {
7774 // Only unwrap the * and & unary operators
7775 const UnaryOperator *UO = cast<UnaryOperator>(expr);
7776 expr = UO->getSubExpr();
7777 switch (UO->getOpcode()) {
7789 case Stmt::ConditionalOperatorClass: {
7790 const ConditionalOperator *cond = cast<ConditionalOperator>(expr);
7791 if (const Expr *lhs = cond->getLHS())
7792 CheckArrayAccess(lhs);
7793 if (const Expr *rhs = cond->getRHS())
7794 CheckArrayAccess(rhs);
7803 //===--- CHECK: Objective-C retain cycles ----------------------------------//
7806 struct RetainCycleOwner {
7807 RetainCycleOwner() : Variable(nullptr), Indirect(false) {}
7813 void setLocsFrom(Expr *e) {
7814 Loc = e->getExprLoc();
7815 Range = e->getSourceRange();
7820 /// Consider whether capturing the given variable can possibly lead to
7822 static bool considerVariable(VarDecl *var, Expr *ref, RetainCycleOwner &owner) {
7823 // In ARC, it's captured strongly iff the variable has __strong
7824 // lifetime. In MRR, it's captured strongly if the variable is
7825 // __block and has an appropriate type.
7826 if (var->getType().getObjCLifetime() != Qualifiers::OCL_Strong)
7829 owner.Variable = var;
7831 owner.setLocsFrom(ref);
7835 static bool findRetainCycleOwner(Sema &S, Expr *e, RetainCycleOwner &owner) {
7837 e = e->IgnoreParens();
7838 if (CastExpr *cast = dyn_cast<CastExpr>(e)) {
7839 switch (cast->getCastKind()) {
7841 case CK_LValueBitCast:
7842 case CK_LValueToRValue:
7843 case CK_ARCReclaimReturnedObject:
7844 e = cast->getSubExpr();
7852 if (ObjCIvarRefExpr *ref = dyn_cast<ObjCIvarRefExpr>(e)) {
7853 ObjCIvarDecl *ivar = ref->getDecl();
7854 if (ivar->getType().getObjCLifetime() != Qualifiers::OCL_Strong)
7857 // Try to find a retain cycle in the base.
7858 if (!findRetainCycleOwner(S, ref->getBase(), owner))
7861 if (ref->isFreeIvar()) owner.setLocsFrom(ref);
7862 owner.Indirect = true;
7866 if (DeclRefExpr *ref = dyn_cast<DeclRefExpr>(e)) {
7867 VarDecl *var = dyn_cast<VarDecl>(ref->getDecl());
7868 if (!var) return false;
7869 return considerVariable(var, ref, owner);
7872 if (MemberExpr *member = dyn_cast<MemberExpr>(e)) {
7873 if (member->isArrow()) return false;
7875 // Don't count this as an indirect ownership.
7876 e = member->getBase();
7880 if (PseudoObjectExpr *pseudo = dyn_cast<PseudoObjectExpr>(e)) {
7881 // Only pay attention to pseudo-objects on property references.
7882 ObjCPropertyRefExpr *pre
7883 = dyn_cast<ObjCPropertyRefExpr>(pseudo->getSyntacticForm()
7885 if (!pre) return false;
7886 if (pre->isImplicitProperty()) return false;
7887 ObjCPropertyDecl *property = pre->getExplicitProperty();
7888 if (!property->isRetaining() &&
7889 !(property->getPropertyIvarDecl() &&
7890 property->getPropertyIvarDecl()->getType()
7891 .getObjCLifetime() == Qualifiers::OCL_Strong))
7894 owner.Indirect = true;
7895 if (pre->isSuperReceiver()) {
7896 owner.Variable = S.getCurMethodDecl()->getSelfDecl();
7897 if (!owner.Variable)
7899 owner.Loc = pre->getLocation();
7900 owner.Range = pre->getSourceRange();
7903 e = const_cast<Expr*>(cast<OpaqueValueExpr>(pre->getBase())
7915 struct FindCaptureVisitor : EvaluatedExprVisitor<FindCaptureVisitor> {
7916 FindCaptureVisitor(ASTContext &Context, VarDecl *variable)
7917 : EvaluatedExprVisitor<FindCaptureVisitor>(Context),
7918 Context(Context), Variable(variable), Capturer(nullptr),
7919 VarWillBeReased(false) {}
7920 ASTContext &Context;
7923 bool VarWillBeReased;
7925 void VisitDeclRefExpr(DeclRefExpr *ref) {
7926 if (ref->getDecl() == Variable && !Capturer)
7930 void VisitObjCIvarRefExpr(ObjCIvarRefExpr *ref) {
7931 if (Capturer) return;
7932 Visit(ref->getBase());
7933 if (Capturer && ref->isFreeIvar())
7937 void VisitBlockExpr(BlockExpr *block) {
7938 // Look inside nested blocks
7939 if (block->getBlockDecl()->capturesVariable(Variable))
7940 Visit(block->getBlockDecl()->getBody());
7943 void VisitOpaqueValueExpr(OpaqueValueExpr *OVE) {
7944 if (Capturer) return;
7945 if (OVE->getSourceExpr())
7946 Visit(OVE->getSourceExpr());
7948 void VisitBinaryOperator(BinaryOperator *BinOp) {
7949 if (!Variable || VarWillBeReased || BinOp->getOpcode() != BO_Assign)
7951 Expr *LHS = BinOp->getLHS();
7952 if (const DeclRefExpr *DRE = dyn_cast_or_null<DeclRefExpr>(LHS)) {
7953 if (DRE->getDecl() != Variable)
7955 if (Expr *RHS = BinOp->getRHS()) {
7956 RHS = RHS->IgnoreParenCasts();
7959 (RHS && RHS->isIntegerConstantExpr(Value, Context) && Value == 0);
7966 /// Check whether the given argument is a block which captures a
7968 static Expr *findCapturingExpr(Sema &S, Expr *e, RetainCycleOwner &owner) {
7969 assert(owner.Variable && owner.Loc.isValid());
7971 e = e->IgnoreParenCasts();
7973 // Look through [^{...} copy] and Block_copy(^{...}).
7974 if (ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(e)) {
7975 Selector Cmd = ME->getSelector();
7976 if (Cmd.isUnarySelector() && Cmd.getNameForSlot(0) == "copy") {
7977 e = ME->getInstanceReceiver();
7980 e = e->IgnoreParenCasts();
7982 } else if (CallExpr *CE = dyn_cast<CallExpr>(e)) {
7983 if (CE->getNumArgs() == 1) {
7984 FunctionDecl *Fn = dyn_cast_or_null<FunctionDecl>(CE->getCalleeDecl());
7986 const IdentifierInfo *FnI = Fn->getIdentifier();
7987 if (FnI && FnI->isStr("_Block_copy")) {
7988 e = CE->getArg(0)->IgnoreParenCasts();
7994 BlockExpr *block = dyn_cast<BlockExpr>(e);
7995 if (!block || !block->getBlockDecl()->capturesVariable(owner.Variable))
7998 FindCaptureVisitor visitor(S.Context, owner.Variable);
7999 visitor.Visit(block->getBlockDecl()->getBody());
8000 return visitor.VarWillBeReased ? nullptr : visitor.Capturer;
8003 static void diagnoseRetainCycle(Sema &S, Expr *capturer,
8004 RetainCycleOwner &owner) {
8006 assert(owner.Variable && owner.Loc.isValid());
8008 S.Diag(capturer->getExprLoc(), diag::warn_arc_retain_cycle)
8009 << owner.Variable << capturer->getSourceRange();
8010 S.Diag(owner.Loc, diag::note_arc_retain_cycle_owner)
8011 << owner.Indirect << owner.Range;
8014 /// Check for a keyword selector that starts with the word 'add' or
8016 static bool isSetterLikeSelector(Selector sel) {
8017 if (sel.isUnarySelector()) return false;
8019 StringRef str = sel.getNameForSlot(0);
8020 while (!str.empty() && str.front() == '_') str = str.substr(1);
8021 if (str.startswith("set"))
8022 str = str.substr(3);
8023 else if (str.startswith("add")) {
8024 // Specially whitelist 'addOperationWithBlock:'.
8025 if (sel.getNumArgs() == 1 && str.startswith("addOperationWithBlock"))
8027 str = str.substr(3);
8032 if (str.empty()) return true;
8033 return !isLowercase(str.front());
8036 /// Check a message send to see if it's likely to cause a retain cycle.
8037 void Sema::checkRetainCycles(ObjCMessageExpr *msg) {
8038 // Only check instance methods whose selector looks like a setter.
8039 if (!msg->isInstanceMessage() || !isSetterLikeSelector(msg->getSelector()))
8042 // Try to find a variable that the receiver is strongly owned by.
8043 RetainCycleOwner owner;
8044 if (msg->getReceiverKind() == ObjCMessageExpr::Instance) {
8045 if (!findRetainCycleOwner(*this, msg->getInstanceReceiver(), owner))
8048 assert(msg->getReceiverKind() == ObjCMessageExpr::SuperInstance);
8049 owner.Variable = getCurMethodDecl()->getSelfDecl();
8050 owner.Loc = msg->getSuperLoc();
8051 owner.Range = msg->getSuperLoc();
8054 // Check whether the receiver is captured by any of the arguments.
8055 for (unsigned i = 0, e = msg->getNumArgs(); i != e; ++i)
8056 if (Expr *capturer = findCapturingExpr(*this, msg->getArg(i), owner))
8057 return diagnoseRetainCycle(*this, capturer, owner);
8060 /// Check a property assign to see if it's likely to cause a retain cycle.
8061 void Sema::checkRetainCycles(Expr *receiver, Expr *argument) {
8062 RetainCycleOwner owner;
8063 if (!findRetainCycleOwner(*this, receiver, owner))
8066 if (Expr *capturer = findCapturingExpr(*this, argument, owner))
8067 diagnoseRetainCycle(*this, capturer, owner);
8070 void Sema::checkRetainCycles(VarDecl *Var, Expr *Init) {
8071 RetainCycleOwner Owner;
8072 if (!considerVariable(Var, /*DeclRefExpr=*/nullptr, Owner))
8075 // Because we don't have an expression for the variable, we have to set the
8076 // location explicitly here.
8077 Owner.Loc = Var->getLocation();
8078 Owner.Range = Var->getSourceRange();
8080 if (Expr *Capturer = findCapturingExpr(*this, Init, Owner))
8081 diagnoseRetainCycle(*this, Capturer, Owner);
8084 static bool checkUnsafeAssignLiteral(Sema &S, SourceLocation Loc,
8085 Expr *RHS, bool isProperty) {
8086 // Check if RHS is an Objective-C object literal, which also can get
8087 // immediately zapped in a weak reference. Note that we explicitly
8088 // allow ObjCStringLiterals, since those are designed to never really die.
8089 RHS = RHS->IgnoreParenImpCasts();
8091 // This enum needs to match with the 'select' in
8092 // warn_objc_arc_literal_assign (off-by-1).
8093 Sema::ObjCLiteralKind Kind = S.CheckLiteralKind(RHS);
8094 if (Kind == Sema::LK_String || Kind == Sema::LK_None)
8097 S.Diag(Loc, diag::warn_arc_literal_assign)
8099 << (isProperty ? 0 : 1)
8100 << RHS->getSourceRange();
8105 static bool checkUnsafeAssignObject(Sema &S, SourceLocation Loc,
8106 Qualifiers::ObjCLifetime LT,
8107 Expr *RHS, bool isProperty) {
8108 // Strip off any implicit cast added to get to the one ARC-specific.
8109 while (ImplicitCastExpr *cast = dyn_cast<ImplicitCastExpr>(RHS)) {
8110 if (cast->getCastKind() == CK_ARCConsumeObject) {
8111 S.Diag(Loc, diag::warn_arc_retained_assign)
8112 << (LT == Qualifiers::OCL_ExplicitNone)
8113 << (isProperty ? 0 : 1)
8114 << RHS->getSourceRange();
8117 RHS = cast->getSubExpr();
8120 if (LT == Qualifiers::OCL_Weak &&
8121 checkUnsafeAssignLiteral(S, Loc, RHS, isProperty))
8127 bool Sema::checkUnsafeAssigns(SourceLocation Loc,
8128 QualType LHS, Expr *RHS) {
8129 Qualifiers::ObjCLifetime LT = LHS.getObjCLifetime();
8131 if (LT != Qualifiers::OCL_Weak && LT != Qualifiers::OCL_ExplicitNone)
8134 if (checkUnsafeAssignObject(*this, Loc, LT, RHS, false))
8140 void Sema::checkUnsafeExprAssigns(SourceLocation Loc,
8141 Expr *LHS, Expr *RHS) {
8143 // PropertyRef on LHS type need be directly obtained from
8144 // its declaration as it has a PseudoType.
8145 ObjCPropertyRefExpr *PRE
8146 = dyn_cast<ObjCPropertyRefExpr>(LHS->IgnoreParens());
8147 if (PRE && !PRE->isImplicitProperty()) {
8148 const ObjCPropertyDecl *PD = PRE->getExplicitProperty();
8150 LHSType = PD->getType();
8153 if (LHSType.isNull())
8154 LHSType = LHS->getType();
8156 Qualifiers::ObjCLifetime LT = LHSType.getObjCLifetime();
8158 if (LT == Qualifiers::OCL_Weak) {
8159 if (!Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, Loc))
8160 getCurFunction()->markSafeWeakUse(LHS);
8163 if (checkUnsafeAssigns(Loc, LHSType, RHS))
8166 // FIXME. Check for other life times.
8167 if (LT != Qualifiers::OCL_None)
8171 if (PRE->isImplicitProperty())
8173 const ObjCPropertyDecl *PD = PRE->getExplicitProperty();
8177 unsigned Attributes = PD->getPropertyAttributes();
8178 if (Attributes & ObjCPropertyDecl::OBJC_PR_assign) {
8179 // when 'assign' attribute was not explicitly specified
8180 // by user, ignore it and rely on property type itself
8181 // for lifetime info.
8182 unsigned AsWrittenAttr = PD->getPropertyAttributesAsWritten();
8183 if (!(AsWrittenAttr & ObjCPropertyDecl::OBJC_PR_assign) &&
8184 LHSType->isObjCRetainableType())
8187 while (ImplicitCastExpr *cast = dyn_cast<ImplicitCastExpr>(RHS)) {
8188 if (cast->getCastKind() == CK_ARCConsumeObject) {
8189 Diag(Loc, diag::warn_arc_retained_property_assign)
8190 << RHS->getSourceRange();
8193 RHS = cast->getSubExpr();
8196 else if (Attributes & ObjCPropertyDecl::OBJC_PR_weak) {
8197 if (checkUnsafeAssignObject(*this, Loc, Qualifiers::OCL_Weak, RHS, true))
8203 //===--- CHECK: Empty statement body (-Wempty-body) ---------------------===//
8206 bool ShouldDiagnoseEmptyStmtBody(const SourceManager &SourceMgr,
8207 SourceLocation StmtLoc,
8208 const NullStmt *Body) {
8209 // Do not warn if the body is a macro that expands to nothing, e.g:
8215 if (Body->hasLeadingEmptyMacro())
8218 // Get line numbers of statement and body.
8219 bool StmtLineInvalid;
8220 unsigned StmtLine = SourceMgr.getSpellingLineNumber(StmtLoc,
8222 if (StmtLineInvalid)
8225 bool BodyLineInvalid;
8226 unsigned BodyLine = SourceMgr.getSpellingLineNumber(Body->getSemiLoc(),
8228 if (BodyLineInvalid)
8231 // Warn if null statement and body are on the same line.
8232 if (StmtLine != BodyLine)
8237 } // Unnamed namespace
8239 void Sema::DiagnoseEmptyStmtBody(SourceLocation StmtLoc,
8242 // Since this is a syntactic check, don't emit diagnostic for template
8243 // instantiations, this just adds noise.
8244 if (CurrentInstantiationScope)
8247 // The body should be a null statement.
8248 const NullStmt *NBody = dyn_cast<NullStmt>(Body);
8252 // Do the usual checks.
8253 if (!ShouldDiagnoseEmptyStmtBody(SourceMgr, StmtLoc, NBody))
8256 Diag(NBody->getSemiLoc(), DiagID);
8257 Diag(NBody->getSemiLoc(), diag::note_empty_body_on_separate_line);
8260 void Sema::DiagnoseEmptyLoopBody(const Stmt *S,
8261 const Stmt *PossibleBody) {
8262 assert(!CurrentInstantiationScope); // Ensured by caller
8264 SourceLocation StmtLoc;
8267 if (const ForStmt *FS = dyn_cast<ForStmt>(S)) {
8268 StmtLoc = FS->getRParenLoc();
8269 Body = FS->getBody();
8270 DiagID = diag::warn_empty_for_body;
8271 } else if (const WhileStmt *WS = dyn_cast<WhileStmt>(S)) {
8272 StmtLoc = WS->getCond()->getSourceRange().getEnd();
8273 Body = WS->getBody();
8274 DiagID = diag::warn_empty_while_body;
8276 return; // Neither `for' nor `while'.
8278 // The body should be a null statement.
8279 const NullStmt *NBody = dyn_cast<NullStmt>(Body);
8283 // Skip expensive checks if diagnostic is disabled.
8284 if (Diags.isIgnored(DiagID, NBody->getSemiLoc()))
8287 // Do the usual checks.
8288 if (!ShouldDiagnoseEmptyStmtBody(SourceMgr, StmtLoc, NBody))
8291 // `for(...);' and `while(...);' are popular idioms, so in order to keep
8292 // noise level low, emit diagnostics only if for/while is followed by a
8293 // CompoundStmt, e.g.:
8294 // for (int i = 0; i < n; i++);
8298 // or if for/while is followed by a statement with more indentation
8299 // than for/while itself:
8300 // for (int i = 0; i < n; i++);
8302 bool ProbableTypo = isa<CompoundStmt>(PossibleBody);
8303 if (!ProbableTypo) {
8304 bool BodyColInvalid;
8305 unsigned BodyCol = SourceMgr.getPresumedColumnNumber(
8306 PossibleBody->getLocStart(),
8311 bool StmtColInvalid;
8312 unsigned StmtCol = SourceMgr.getPresumedColumnNumber(
8318 if (BodyCol > StmtCol)
8319 ProbableTypo = true;
8323 Diag(NBody->getSemiLoc(), DiagID);
8324 Diag(NBody->getSemiLoc(), diag::note_empty_body_on_separate_line);
8328 //===--- CHECK: Warn on self move with std::move. -------------------------===//
8330 /// DiagnoseSelfMove - Emits a warning if a value is moved to itself.
8331 void Sema::DiagnoseSelfMove(const Expr *LHSExpr, const Expr *RHSExpr,
8332 SourceLocation OpLoc) {
8334 if (Diags.isIgnored(diag::warn_sizeof_pointer_expr_memaccess, OpLoc))
8337 if (!ActiveTemplateInstantiations.empty())
8340 // Strip parens and casts away.
8341 LHSExpr = LHSExpr->IgnoreParenImpCasts();
8342 RHSExpr = RHSExpr->IgnoreParenImpCasts();
8344 // Check for a call expression
8345 const CallExpr *CE = dyn_cast<CallExpr>(RHSExpr);
8346 if (!CE || CE->getNumArgs() != 1)
8349 // Check for a call to std::move
8350 const FunctionDecl *FD = CE->getDirectCallee();
8351 if (!FD || !FD->isInStdNamespace() || !FD->getIdentifier() ||
8352 !FD->getIdentifier()->isStr("move"))
8355 // Get argument from std::move
8356 RHSExpr = CE->getArg(0);
8358 const DeclRefExpr *LHSDeclRef = dyn_cast<DeclRefExpr>(LHSExpr);
8359 const DeclRefExpr *RHSDeclRef = dyn_cast<DeclRefExpr>(RHSExpr);
8361 // Two DeclRefExpr's, check that the decls are the same.
8362 if (LHSDeclRef && RHSDeclRef) {
8363 if (!LHSDeclRef->getDecl() || !RHSDeclRef->getDecl())
8365 if (LHSDeclRef->getDecl()->getCanonicalDecl() !=
8366 RHSDeclRef->getDecl()->getCanonicalDecl())
8369 Diag(OpLoc, diag::warn_self_move) << LHSExpr->getType()
8370 << LHSExpr->getSourceRange()
8371 << RHSExpr->getSourceRange();
8375 // Member variables require a different approach to check for self moves.
8376 // MemberExpr's are the same if every nested MemberExpr refers to the same
8377 // Decl and that the base Expr's are DeclRefExpr's with the same Decl or
8378 // the base Expr's are CXXThisExpr's.
8379 const Expr *LHSBase = LHSExpr;
8380 const Expr *RHSBase = RHSExpr;
8381 const MemberExpr *LHSME = dyn_cast<MemberExpr>(LHSExpr);
8382 const MemberExpr *RHSME = dyn_cast<MemberExpr>(RHSExpr);
8383 if (!LHSME || !RHSME)
8386 while (LHSME && RHSME) {
8387 if (LHSME->getMemberDecl()->getCanonicalDecl() !=
8388 RHSME->getMemberDecl()->getCanonicalDecl())
8391 LHSBase = LHSME->getBase();
8392 RHSBase = RHSME->getBase();
8393 LHSME = dyn_cast<MemberExpr>(LHSBase);
8394 RHSME = dyn_cast<MemberExpr>(RHSBase);
8397 LHSDeclRef = dyn_cast<DeclRefExpr>(LHSBase);
8398 RHSDeclRef = dyn_cast<DeclRefExpr>(RHSBase);
8399 if (LHSDeclRef && RHSDeclRef) {
8400 if (!LHSDeclRef->getDecl() || !RHSDeclRef->getDecl())
8402 if (LHSDeclRef->getDecl()->getCanonicalDecl() !=
8403 RHSDeclRef->getDecl()->getCanonicalDecl())
8406 Diag(OpLoc, diag::warn_self_move) << LHSExpr->getType()
8407 << LHSExpr->getSourceRange()
8408 << RHSExpr->getSourceRange();
8412 if (isa<CXXThisExpr>(LHSBase) && isa<CXXThisExpr>(RHSBase))
8413 Diag(OpLoc, diag::warn_self_move) << LHSExpr->getType()
8414 << LHSExpr->getSourceRange()
8415 << RHSExpr->getSourceRange();
8418 //===--- Layout compatibility ----------------------------------------------//
8422 bool isLayoutCompatible(ASTContext &C, QualType T1, QualType T2);
8424 /// \brief Check if two enumeration types are layout-compatible.
8425 bool isLayoutCompatible(ASTContext &C, EnumDecl *ED1, EnumDecl *ED2) {
8426 // C++11 [dcl.enum] p8:
8427 // Two enumeration types are layout-compatible if they have the same
8429 return ED1->isComplete() && ED2->isComplete() &&
8430 C.hasSameType(ED1->getIntegerType(), ED2->getIntegerType());
8433 /// \brief Check if two fields are layout-compatible.
8434 bool isLayoutCompatible(ASTContext &C, FieldDecl *Field1, FieldDecl *Field2) {
8435 if (!isLayoutCompatible(C, Field1->getType(), Field2->getType()))
8438 if (Field1->isBitField() != Field2->isBitField())
8441 if (Field1->isBitField()) {
8442 // Make sure that the bit-fields are the same length.
8443 unsigned Bits1 = Field1->getBitWidthValue(C);
8444 unsigned Bits2 = Field2->getBitWidthValue(C);
8453 /// \brief Check if two standard-layout structs are layout-compatible.
8454 /// (C++11 [class.mem] p17)
8455 bool isLayoutCompatibleStruct(ASTContext &C,
8458 // If both records are C++ classes, check that base classes match.
8459 if (const CXXRecordDecl *D1CXX = dyn_cast<CXXRecordDecl>(RD1)) {
8460 // If one of records is a CXXRecordDecl we are in C++ mode,
8461 // thus the other one is a CXXRecordDecl, too.
8462 const CXXRecordDecl *D2CXX = cast<CXXRecordDecl>(RD2);
8463 // Check number of base classes.
8464 if (D1CXX->getNumBases() != D2CXX->getNumBases())
8467 // Check the base classes.
8468 for (CXXRecordDecl::base_class_const_iterator
8469 Base1 = D1CXX->bases_begin(),
8470 BaseEnd1 = D1CXX->bases_end(),
8471 Base2 = D2CXX->bases_begin();
8474 if (!isLayoutCompatible(C, Base1->getType(), Base2->getType()))
8477 } else if (const CXXRecordDecl *D2CXX = dyn_cast<CXXRecordDecl>(RD2)) {
8478 // If only RD2 is a C++ class, it should have zero base classes.
8479 if (D2CXX->getNumBases() > 0)
8483 // Check the fields.
8484 RecordDecl::field_iterator Field2 = RD2->field_begin(),
8485 Field2End = RD2->field_end(),
8486 Field1 = RD1->field_begin(),
8487 Field1End = RD1->field_end();
8488 for ( ; Field1 != Field1End && Field2 != Field2End; ++Field1, ++Field2) {
8489 if (!isLayoutCompatible(C, *Field1, *Field2))
8492 if (Field1 != Field1End || Field2 != Field2End)
8498 /// \brief Check if two standard-layout unions are layout-compatible.
8499 /// (C++11 [class.mem] p18)
8500 bool isLayoutCompatibleUnion(ASTContext &C,
8503 llvm::SmallPtrSet<FieldDecl *, 8> UnmatchedFields;
8504 for (auto *Field2 : RD2->fields())
8505 UnmatchedFields.insert(Field2);
8507 for (auto *Field1 : RD1->fields()) {
8508 llvm::SmallPtrSet<FieldDecl *, 8>::iterator
8509 I = UnmatchedFields.begin(),
8510 E = UnmatchedFields.end();
8512 for ( ; I != E; ++I) {
8513 if (isLayoutCompatible(C, Field1, *I)) {
8514 bool Result = UnmatchedFields.erase(*I);
8524 return UnmatchedFields.empty();
8527 bool isLayoutCompatible(ASTContext &C, RecordDecl *RD1, RecordDecl *RD2) {
8528 if (RD1->isUnion() != RD2->isUnion())
8532 return isLayoutCompatibleUnion(C, RD1, RD2);
8534 return isLayoutCompatibleStruct(C, RD1, RD2);
8537 /// \brief Check if two types are layout-compatible in C++11 sense.
8538 bool isLayoutCompatible(ASTContext &C, QualType T1, QualType T2) {
8539 if (T1.isNull() || T2.isNull())
8542 // C++11 [basic.types] p11:
8543 // If two types T1 and T2 are the same type, then T1 and T2 are
8544 // layout-compatible types.
8545 if (C.hasSameType(T1, T2))
8548 T1 = T1.getCanonicalType().getUnqualifiedType();
8549 T2 = T2.getCanonicalType().getUnqualifiedType();
8551 const Type::TypeClass TC1 = T1->getTypeClass();
8552 const Type::TypeClass TC2 = T2->getTypeClass();
8557 if (TC1 == Type::Enum) {
8558 return isLayoutCompatible(C,
8559 cast<EnumType>(T1)->getDecl(),
8560 cast<EnumType>(T2)->getDecl());
8561 } else if (TC1 == Type::Record) {
8562 if (!T1->isStandardLayoutType() || !T2->isStandardLayoutType())
8565 return isLayoutCompatible(C,
8566 cast<RecordType>(T1)->getDecl(),
8567 cast<RecordType>(T2)->getDecl());
8574 //===--- CHECK: pointer_with_type_tag attribute: datatypes should match ----//
8577 /// \brief Given a type tag expression find the type tag itself.
8579 /// \param TypeExpr Type tag expression, as it appears in user's code.
8581 /// \param VD Declaration of an identifier that appears in a type tag.
8583 /// \param MagicValue Type tag magic value.
8584 bool FindTypeTagExpr(const Expr *TypeExpr, const ASTContext &Ctx,
8585 const ValueDecl **VD, uint64_t *MagicValue) {
8590 TypeExpr = TypeExpr->IgnoreParenImpCasts()->IgnoreParenCasts();
8592 switch (TypeExpr->getStmtClass()) {
8593 case Stmt::UnaryOperatorClass: {
8594 const UnaryOperator *UO = cast<UnaryOperator>(TypeExpr);
8595 if (UO->getOpcode() == UO_AddrOf || UO->getOpcode() == UO_Deref) {
8596 TypeExpr = UO->getSubExpr();
8602 case Stmt::DeclRefExprClass: {
8603 const DeclRefExpr *DRE = cast<DeclRefExpr>(TypeExpr);
8604 *VD = DRE->getDecl();
8608 case Stmt::IntegerLiteralClass: {
8609 const IntegerLiteral *IL = cast<IntegerLiteral>(TypeExpr);
8610 llvm::APInt MagicValueAPInt = IL->getValue();
8611 if (MagicValueAPInt.getActiveBits() <= 64) {
8612 *MagicValue = MagicValueAPInt.getZExtValue();
8618 case Stmt::BinaryConditionalOperatorClass:
8619 case Stmt::ConditionalOperatorClass: {
8620 const AbstractConditionalOperator *ACO =
8621 cast<AbstractConditionalOperator>(TypeExpr);
8623 if (ACO->getCond()->EvaluateAsBooleanCondition(Result, Ctx)) {
8625 TypeExpr = ACO->getTrueExpr();
8627 TypeExpr = ACO->getFalseExpr();
8633 case Stmt::BinaryOperatorClass: {
8634 const BinaryOperator *BO = cast<BinaryOperator>(TypeExpr);
8635 if (BO->getOpcode() == BO_Comma) {
8636 TypeExpr = BO->getRHS();
8648 /// \brief Retrieve the C type corresponding to type tag TypeExpr.
8650 /// \param TypeExpr Expression that specifies a type tag.
8652 /// \param MagicValues Registered magic values.
8654 /// \param FoundWrongKind Set to true if a type tag was found, but of a wrong
8657 /// \param TypeInfo Information about the corresponding C type.
8659 /// \returns true if the corresponding C type was found.
8660 bool GetMatchingCType(
8661 const IdentifierInfo *ArgumentKind,
8662 const Expr *TypeExpr, const ASTContext &Ctx,
8663 const llvm::DenseMap<Sema::TypeTagMagicValue,
8664 Sema::TypeTagData> *MagicValues,
8665 bool &FoundWrongKind,
8666 Sema::TypeTagData &TypeInfo) {
8667 FoundWrongKind = false;
8669 // Variable declaration that has type_tag_for_datatype attribute.
8670 const ValueDecl *VD = nullptr;
8672 uint64_t MagicValue;
8674 if (!FindTypeTagExpr(TypeExpr, Ctx, &VD, &MagicValue))
8678 if (TypeTagForDatatypeAttr *I = VD->getAttr<TypeTagForDatatypeAttr>()) {
8679 if (I->getArgumentKind() != ArgumentKind) {
8680 FoundWrongKind = true;
8683 TypeInfo.Type = I->getMatchingCType();
8684 TypeInfo.LayoutCompatible = I->getLayoutCompatible();
8685 TypeInfo.MustBeNull = I->getMustBeNull();
8694 llvm::DenseMap<Sema::TypeTagMagicValue,
8695 Sema::TypeTagData>::const_iterator I =
8696 MagicValues->find(std::make_pair(ArgumentKind, MagicValue));
8697 if (I == MagicValues->end())
8700 TypeInfo = I->second;
8703 } // unnamed namespace
8705 void Sema::RegisterTypeTagForDatatype(const IdentifierInfo *ArgumentKind,
8706 uint64_t MagicValue, QualType Type,
8707 bool LayoutCompatible,
8709 if (!TypeTagForDatatypeMagicValues)
8710 TypeTagForDatatypeMagicValues.reset(
8711 new llvm::DenseMap<TypeTagMagicValue, TypeTagData>);
8713 TypeTagMagicValue Magic(ArgumentKind, MagicValue);
8714 (*TypeTagForDatatypeMagicValues)[Magic] =
8715 TypeTagData(Type, LayoutCompatible, MustBeNull);
8719 bool IsSameCharType(QualType T1, QualType T2) {
8720 const BuiltinType *BT1 = T1->getAs<BuiltinType>();
8724 const BuiltinType *BT2 = T2->getAs<BuiltinType>();
8728 BuiltinType::Kind T1Kind = BT1->getKind();
8729 BuiltinType::Kind T2Kind = BT2->getKind();
8731 return (T1Kind == BuiltinType::SChar && T2Kind == BuiltinType::Char_S) ||
8732 (T1Kind == BuiltinType::UChar && T2Kind == BuiltinType::Char_U) ||
8733 (T1Kind == BuiltinType::Char_U && T2Kind == BuiltinType::UChar) ||
8734 (T1Kind == BuiltinType::Char_S && T2Kind == BuiltinType::SChar);
8736 } // unnamed namespace
8738 void Sema::CheckArgumentWithTypeTag(const ArgumentWithTypeTagAttr *Attr,
8739 const Expr * const *ExprArgs) {
8740 const IdentifierInfo *ArgumentKind = Attr->getArgumentKind();
8741 bool IsPointerAttr = Attr->getIsPointer();
8743 const Expr *TypeTagExpr = ExprArgs[Attr->getTypeTagIdx()];
8744 bool FoundWrongKind;
8745 TypeTagData TypeInfo;
8746 if (!GetMatchingCType(ArgumentKind, TypeTagExpr, Context,
8747 TypeTagForDatatypeMagicValues.get(),
8748 FoundWrongKind, TypeInfo)) {
8750 Diag(TypeTagExpr->getExprLoc(),
8751 diag::warn_type_tag_for_datatype_wrong_kind)
8752 << TypeTagExpr->getSourceRange();
8756 const Expr *ArgumentExpr = ExprArgs[Attr->getArgumentIdx()];
8757 if (IsPointerAttr) {
8758 // Skip implicit cast of pointer to `void *' (as a function argument).
8759 if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgumentExpr))
8760 if (ICE->getType()->isVoidPointerType() &&
8761 ICE->getCastKind() == CK_BitCast)
8762 ArgumentExpr = ICE->getSubExpr();
8764 QualType ArgumentType = ArgumentExpr->getType();
8766 // Passing a `void*' pointer shouldn't trigger a warning.
8767 if (IsPointerAttr && ArgumentType->isVoidPointerType())
8770 if (TypeInfo.MustBeNull) {
8771 // Type tag with matching void type requires a null pointer.
8772 if (!ArgumentExpr->isNullPointerConstant(Context,
8773 Expr::NPC_ValueDependentIsNotNull)) {
8774 Diag(ArgumentExpr->getExprLoc(),
8775 diag::warn_type_safety_null_pointer_required)
8776 << ArgumentKind->getName()
8777 << ArgumentExpr->getSourceRange()
8778 << TypeTagExpr->getSourceRange();
8783 QualType RequiredType = TypeInfo.Type;
8785 RequiredType = Context.getPointerType(RequiredType);
8787 bool mismatch = false;
8788 if (!TypeInfo.LayoutCompatible) {
8789 mismatch = !Context.hasSameType(ArgumentType, RequiredType);
8791 // C++11 [basic.fundamental] p1:
8792 // Plain char, signed char, and unsigned char are three distinct types.
8794 // But we treat plain `char' as equivalent to `signed char' or `unsigned
8795 // char' depending on the current char signedness mode.
8797 if ((IsPointerAttr && IsSameCharType(ArgumentType->getPointeeType(),
8798 RequiredType->getPointeeType())) ||
8799 (!IsPointerAttr && IsSameCharType(ArgumentType, RequiredType)))
8803 mismatch = !isLayoutCompatible(Context,
8804 ArgumentType->getPointeeType(),
8805 RequiredType->getPointeeType());
8807 mismatch = !isLayoutCompatible(Context, ArgumentType, RequiredType);
8810 Diag(ArgumentExpr->getExprLoc(), diag::warn_type_safety_type_mismatch)
8811 << ArgumentType << ArgumentKind
8812 << TypeInfo.LayoutCompatible << RequiredType
8813 << ArgumentExpr->getSourceRange()
8814 << TypeTagExpr->getSourceRange();