1 //===--- SemaStmt.cpp - Semantic Analysis for Statements ------------------===//
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 semantic analysis for statements.
12 //===----------------------------------------------------------------------===//
14 #include "clang/Sema/SemaInternal.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/ASTDiagnostic.h"
17 #include "clang/AST/CharUnits.h"
18 #include "clang/AST/DeclObjC.h"
19 #include "clang/AST/EvaluatedExprVisitor.h"
20 #include "clang/AST/ExprCXX.h"
21 #include "clang/AST/ExprObjC.h"
22 #include "clang/AST/StmtCXX.h"
23 #include "clang/AST/StmtObjC.h"
24 #include "clang/AST/TypeLoc.h"
25 #include "clang/Lex/Preprocessor.h"
26 #include "clang/Sema/Initialization.h"
27 #include "clang/Sema/Lookup.h"
28 #include "clang/Sema/Scope.h"
29 #include "clang/Sema/ScopeInfo.h"
30 #include "llvm/ADT/ArrayRef.h"
31 #include "llvm/ADT/STLExtras.h"
32 #include "llvm/ADT/SmallPtrSet.h"
33 #include "llvm/ADT/SmallString.h"
34 #include "llvm/ADT/SmallVector.h"
35 using namespace clang;
38 StmtResult Sema::ActOnExprStmt(ExprResult FE) {
42 FE = ActOnFinishFullExpr(FE.get(), FE.get()->getExprLoc(),
43 /*DiscardedValue*/ true);
47 // C99 6.8.3p2: The expression in an expression statement is evaluated as a
48 // void expression for its side effects. Conversion to void allows any
49 // operand, even incomplete types.
51 // Same thing in for stmt first clause (when expr) and third clause.
52 return Owned(static_cast<Stmt*>(FE.take()));
56 StmtResult Sema::ActOnExprStmtError() {
57 DiscardCleanupsInEvaluationContext();
61 StmtResult Sema::ActOnNullStmt(SourceLocation SemiLoc,
62 bool HasLeadingEmptyMacro) {
63 return Owned(new (Context) NullStmt(SemiLoc, HasLeadingEmptyMacro));
66 StmtResult Sema::ActOnDeclStmt(DeclGroupPtrTy dg, SourceLocation StartLoc,
67 SourceLocation EndLoc) {
68 DeclGroupRef DG = dg.get();
70 // If we have an invalid decl, just return an error.
71 if (DG.isNull()) return StmtError();
73 return Owned(new (Context) DeclStmt(DG, StartLoc, EndLoc));
76 void Sema::ActOnForEachDeclStmt(DeclGroupPtrTy dg) {
77 DeclGroupRef DG = dg.get();
79 // If we don't have a declaration, or we have an invalid declaration,
81 if (DG.isNull() || !DG.isSingleDecl())
84 Decl *decl = DG.getSingleDecl();
85 if (!decl || decl->isInvalidDecl())
88 // Only variable declarations are permitted.
89 VarDecl *var = dyn_cast<VarDecl>(decl);
91 Diag(decl->getLocation(), diag::err_non_variable_decl_in_for);
92 decl->setInvalidDecl();
96 // foreach variables are never actually initialized in the way that
97 // the parser came up with.
100 // In ARC, we don't need to retain the iteration variable of a fast
101 // enumeration loop. Rather than actually trying to catch that
102 // during declaration processing, we remove the consequences here.
103 if (getLangOpts().ObjCAutoRefCount) {
104 QualType type = var->getType();
106 // Only do this if we inferred the lifetime. Inferred lifetime
107 // will show up as a local qualifier because explicit lifetime
108 // should have shown up as an AttributedType instead.
109 if (type.getLocalQualifiers().getObjCLifetime() == Qualifiers::OCL_Strong) {
110 // Add 'const' and mark the variable as pseudo-strong.
111 var->setType(type.withConst());
112 var->setARCPseudoStrong(true);
117 /// \brief Diagnose unused '==' and '!=' as likely typos for '=' or '|='.
119 /// Adding a cast to void (or other expression wrappers) will prevent the
120 /// warning from firing.
121 static bool DiagnoseUnusedComparison(Sema &S, const Expr *E) {
123 bool IsNotEqual, CanAssign;
125 if (const BinaryOperator *Op = dyn_cast<BinaryOperator>(E)) {
126 if (Op->getOpcode() != BO_EQ && Op->getOpcode() != BO_NE)
129 Loc = Op->getOperatorLoc();
130 IsNotEqual = Op->getOpcode() == BO_NE;
131 CanAssign = Op->getLHS()->IgnoreParenImpCasts()->isLValue();
132 } else if (const CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(E)) {
133 if (Op->getOperator() != OO_EqualEqual &&
134 Op->getOperator() != OO_ExclaimEqual)
137 Loc = Op->getOperatorLoc();
138 IsNotEqual = Op->getOperator() == OO_ExclaimEqual;
139 CanAssign = Op->getArg(0)->IgnoreParenImpCasts()->isLValue();
141 // Not a typo-prone comparison.
145 // Suppress warnings when the operator, suspicious as it may be, comes from
146 // a macro expansion.
147 if (S.SourceMgr.isMacroBodyExpansion(Loc))
150 S.Diag(Loc, diag::warn_unused_comparison)
151 << (unsigned)IsNotEqual << E->getSourceRange();
153 // If the LHS is a plausible entity to assign to, provide a fixit hint to
154 // correct common typos.
157 S.Diag(Loc, diag::note_inequality_comparison_to_or_assign)
158 << FixItHint::CreateReplacement(Loc, "|=");
160 S.Diag(Loc, diag::note_equality_comparison_to_assign)
161 << FixItHint::CreateReplacement(Loc, "=");
167 void Sema::DiagnoseUnusedExprResult(const Stmt *S) {
168 if (const LabelStmt *Label = dyn_cast_or_null<LabelStmt>(S))
169 return DiagnoseUnusedExprResult(Label->getSubStmt());
171 const Expr *E = dyn_cast_or_null<Expr>(S);
174 SourceLocation ExprLoc = E->IgnoreParens()->getExprLoc();
175 // In most cases, we don't want to warn if the expression is written in a
176 // macro body, or if the macro comes from a system header. If the offending
177 // expression is a call to a function with the warn_unused_result attribute,
178 // we warn no matter the location. Because of the order in which the various
179 // checks need to happen, we factor out the macro-related test here.
180 bool ShouldSuppress =
181 SourceMgr.isMacroBodyExpansion(ExprLoc) ||
182 SourceMgr.isInSystemMacro(ExprLoc);
184 const Expr *WarnExpr;
187 if (!E->isUnusedResultAWarning(WarnExpr, Loc, R1, R2, Context))
190 // If this is a GNU statement expression expanded from a macro, it is probably
191 // unused because it is a function-like macro that can be used as either an
192 // expression or statement. Don't warn, because it is almost certainly a
194 if (isa<StmtExpr>(E) && Loc.isMacroID())
197 // Okay, we have an unused result. Depending on what the base expression is,
198 // we might want to make a more specific diagnostic. Check for one of these
200 unsigned DiagID = diag::warn_unused_expr;
201 if (const ExprWithCleanups *Temps = dyn_cast<ExprWithCleanups>(E))
202 E = Temps->getSubExpr();
203 if (const CXXBindTemporaryExpr *TempExpr = dyn_cast<CXXBindTemporaryExpr>(E))
204 E = TempExpr->getSubExpr();
206 if (DiagnoseUnusedComparison(*this, E))
210 if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
211 if (E->getType()->isVoidType())
214 // If the callee has attribute pure, const, or warn_unused_result, warn with
215 // a more specific message to make it clear what is happening. If the call
216 // is written in a macro body, only warn if it has the warn_unused_result
218 if (const Decl *FD = CE->getCalleeDecl()) {
219 if (FD->getAttr<WarnUnusedResultAttr>()) {
220 Diag(Loc, diag::warn_unused_result) << R1 << R2;
225 if (FD->getAttr<PureAttr>()) {
226 Diag(Loc, diag::warn_unused_call) << R1 << R2 << "pure";
229 if (FD->getAttr<ConstAttr>()) {
230 Diag(Loc, diag::warn_unused_call) << R1 << R2 << "const";
234 } else if (ShouldSuppress)
237 if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E)) {
238 if (getLangOpts().ObjCAutoRefCount && ME->isDelegateInitCall()) {
239 Diag(Loc, diag::err_arc_unused_init_message) << R1;
242 const ObjCMethodDecl *MD = ME->getMethodDecl();
243 if (MD && MD->getAttr<WarnUnusedResultAttr>()) {
244 Diag(Loc, diag::warn_unused_result) << R1 << R2;
247 } else if (const PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E)) {
248 const Expr *Source = POE->getSyntacticForm();
249 if (isa<ObjCSubscriptRefExpr>(Source))
250 DiagID = diag::warn_unused_container_subscript_expr;
252 DiagID = diag::warn_unused_property_expr;
253 } else if (const CXXFunctionalCastExpr *FC
254 = dyn_cast<CXXFunctionalCastExpr>(E)) {
255 if (isa<CXXConstructExpr>(FC->getSubExpr()) ||
256 isa<CXXTemporaryObjectExpr>(FC->getSubExpr()))
259 // Diagnose "(void*) blah" as a typo for "(void) blah".
260 else if (const CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(E)) {
261 TypeSourceInfo *TI = CE->getTypeInfoAsWritten();
262 QualType T = TI->getType();
264 // We really do want to use the non-canonical type here.
265 if (T == Context.VoidPtrTy) {
266 PointerTypeLoc TL = TI->getTypeLoc().castAs<PointerTypeLoc>();
268 Diag(Loc, diag::warn_unused_voidptr)
269 << FixItHint::CreateRemoval(TL.getStarLoc());
274 if (E->isGLValue() && E->getType().isVolatileQualified()) {
275 Diag(Loc, diag::warn_unused_volatile) << R1 << R2;
279 DiagRuntimeBehavior(Loc, 0, PDiag(DiagID) << R1 << R2);
282 void Sema::ActOnStartOfCompoundStmt() {
286 void Sema::ActOnFinishOfCompoundStmt() {
290 sema::CompoundScopeInfo &Sema::getCurCompoundScope() const {
291 return getCurFunction()->CompoundScopes.back();
294 StmtResult Sema::ActOnCompoundStmt(SourceLocation L, SourceLocation R,
295 ArrayRef<Stmt *> Elts, bool isStmtExpr) {
296 const unsigned NumElts = Elts.size();
298 // If we're in C89 mode, check that we don't have any decls after stmts. If
299 // so, emit an extension diagnostic.
300 if (!getLangOpts().C99 && !getLangOpts().CPlusPlus) {
301 // Note that __extension__ can be around a decl.
303 // Skip over all declarations.
304 for (; i != NumElts && isa<DeclStmt>(Elts[i]); ++i)
307 // We found the end of the list or a statement. Scan for another declstmt.
308 for (; i != NumElts && !isa<DeclStmt>(Elts[i]); ++i)
312 Decl *D = *cast<DeclStmt>(Elts[i])->decl_begin();
313 Diag(D->getLocation(), diag::ext_mixed_decls_code);
316 // Warn about unused expressions in statements.
317 for (unsigned i = 0; i != NumElts; ++i) {
318 // Ignore statements that are last in a statement expression.
319 if (isStmtExpr && i == NumElts - 1)
322 DiagnoseUnusedExprResult(Elts[i]);
325 // Check for suspicious empty body (null statement) in `for' and `while'
326 // statements. Don't do anything for template instantiations, this just adds
328 if (NumElts != 0 && !CurrentInstantiationScope &&
329 getCurCompoundScope().HasEmptyLoopBodies) {
330 for (unsigned i = 0; i != NumElts - 1; ++i)
331 DiagnoseEmptyLoopBody(Elts[i], Elts[i + 1]);
334 return Owned(new (Context) CompoundStmt(Context, Elts, L, R));
338 Sema::ActOnCaseStmt(SourceLocation CaseLoc, Expr *LHSVal,
339 SourceLocation DotDotDotLoc, Expr *RHSVal,
340 SourceLocation ColonLoc) {
341 assert((LHSVal != 0) && "missing expression in case statement");
343 if (getCurFunction()->SwitchStack.empty()) {
344 Diag(CaseLoc, diag::err_case_not_in_switch);
348 if (!getLangOpts().CPlusPlus11) {
349 // C99 6.8.4.2p3: The expression shall be an integer constant.
350 // However, GCC allows any evaluatable integer expression.
351 if (!LHSVal->isTypeDependent() && !LHSVal->isValueDependent()) {
352 LHSVal = VerifyIntegerConstantExpression(LHSVal).take();
357 // GCC extension: The expression shall be an integer constant.
359 if (RHSVal && !RHSVal->isTypeDependent() && !RHSVal->isValueDependent()) {
360 RHSVal = VerifyIntegerConstantExpression(RHSVal).take();
361 // Recover from an error by just forgetting about it.
365 LHSVal = ActOnFinishFullExpr(LHSVal, LHSVal->getExprLoc(), false,
366 getLangOpts().CPlusPlus11).take();
368 RHSVal = ActOnFinishFullExpr(RHSVal, RHSVal->getExprLoc(), false,
369 getLangOpts().CPlusPlus11).take();
371 CaseStmt *CS = new (Context) CaseStmt(LHSVal, RHSVal, CaseLoc, DotDotDotLoc,
373 getCurFunction()->SwitchStack.back()->addSwitchCase(CS);
377 /// ActOnCaseStmtBody - This installs a statement as the body of a case.
378 void Sema::ActOnCaseStmtBody(Stmt *caseStmt, Stmt *SubStmt) {
379 DiagnoseUnusedExprResult(SubStmt);
381 CaseStmt *CS = static_cast<CaseStmt*>(caseStmt);
382 CS->setSubStmt(SubStmt);
386 Sema::ActOnDefaultStmt(SourceLocation DefaultLoc, SourceLocation ColonLoc,
387 Stmt *SubStmt, Scope *CurScope) {
388 DiagnoseUnusedExprResult(SubStmt);
390 if (getCurFunction()->SwitchStack.empty()) {
391 Diag(DefaultLoc, diag::err_default_not_in_switch);
392 return Owned(SubStmt);
395 DefaultStmt *DS = new (Context) DefaultStmt(DefaultLoc, ColonLoc, SubStmt);
396 getCurFunction()->SwitchStack.back()->addSwitchCase(DS);
401 Sema::ActOnLabelStmt(SourceLocation IdentLoc, LabelDecl *TheDecl,
402 SourceLocation ColonLoc, Stmt *SubStmt) {
403 // If the label was multiply defined, reject it now.
404 if (TheDecl->getStmt()) {
405 Diag(IdentLoc, diag::err_redefinition_of_label) << TheDecl->getDeclName();
406 Diag(TheDecl->getLocation(), diag::note_previous_definition);
407 return Owned(SubStmt);
410 // Otherwise, things are good. Fill in the declaration and return it.
411 LabelStmt *LS = new (Context) LabelStmt(IdentLoc, TheDecl, SubStmt);
412 TheDecl->setStmt(LS);
413 if (!TheDecl->isGnuLocal()) {
414 TheDecl->setLocStart(IdentLoc);
415 TheDecl->setLocation(IdentLoc);
420 StmtResult Sema::ActOnAttributedStmt(SourceLocation AttrLoc,
421 ArrayRef<const Attr*> Attrs,
423 // Fill in the declaration and return it.
424 AttributedStmt *LS = AttributedStmt::Create(Context, AttrLoc, Attrs, SubStmt);
429 Sema::ActOnIfStmt(SourceLocation IfLoc, FullExprArg CondVal, Decl *CondVar,
430 Stmt *thenStmt, SourceLocation ElseLoc,
432 // If the condition was invalid, discard the if statement. We could recover
433 // better by replacing it with a valid expr, but don't do that yet.
434 if (!CondVal.get() && !CondVar) {
435 getCurFunction()->setHasDroppedStmt();
439 ExprResult CondResult(CondVal.release());
441 VarDecl *ConditionVar = 0;
443 ConditionVar = cast<VarDecl>(CondVar);
444 CondResult = CheckConditionVariable(ConditionVar, IfLoc, true);
445 if (CondResult.isInvalid())
448 Expr *ConditionExpr = CondResult.takeAs<Expr>();
452 DiagnoseUnusedExprResult(thenStmt);
455 DiagnoseEmptyStmtBody(ConditionExpr->getLocEnd(), thenStmt,
456 diag::warn_empty_if_body);
459 DiagnoseUnusedExprResult(elseStmt);
461 return Owned(new (Context) IfStmt(Context, IfLoc, ConditionVar, ConditionExpr,
462 thenStmt, ElseLoc, elseStmt));
465 /// ConvertIntegerToTypeWarnOnOverflow - Convert the specified APInt to have
466 /// the specified width and sign. If an overflow occurs, detect it and emit
467 /// the specified diagnostic.
468 void Sema::ConvertIntegerToTypeWarnOnOverflow(llvm::APSInt &Val,
469 unsigned NewWidth, bool NewSign,
472 // Perform a conversion to the promoted condition type if needed.
473 if (NewWidth > Val.getBitWidth()) {
474 // If this is an extension, just do it.
475 Val = Val.extend(NewWidth);
476 Val.setIsSigned(NewSign);
478 // If the input was signed and negative and the output is
479 // unsigned, don't bother to warn: this is implementation-defined
481 // FIXME: Introduce a second, default-ignored warning for this case?
482 } else if (NewWidth < Val.getBitWidth()) {
483 // If this is a truncation, check for overflow.
484 llvm::APSInt ConvVal(Val);
485 ConvVal = ConvVal.trunc(NewWidth);
486 ConvVal.setIsSigned(NewSign);
487 ConvVal = ConvVal.extend(Val.getBitWidth());
488 ConvVal.setIsSigned(Val.isSigned());
490 Diag(Loc, DiagID) << Val.toString(10) << ConvVal.toString(10);
492 // Regardless of whether a diagnostic was emitted, really do the
494 Val = Val.trunc(NewWidth);
495 Val.setIsSigned(NewSign);
496 } else if (NewSign != Val.isSigned()) {
497 // Convert the sign to match the sign of the condition. This can cause
498 // overflow as well: unsigned(INTMIN)
499 // We don't diagnose this overflow, because it is implementation-defined
501 // FIXME: Introduce a second, default-ignored warning for this case?
502 llvm::APSInt OldVal(Val);
503 Val.setIsSigned(NewSign);
508 struct CaseCompareFunctor {
509 bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS,
510 const llvm::APSInt &RHS) {
511 return LHS.first < RHS;
513 bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS,
514 const std::pair<llvm::APSInt, CaseStmt*> &RHS) {
515 return LHS.first < RHS.first;
517 bool operator()(const llvm::APSInt &LHS,
518 const std::pair<llvm::APSInt, CaseStmt*> &RHS) {
519 return LHS < RHS.first;
524 /// CmpCaseVals - Comparison predicate for sorting case values.
526 static bool CmpCaseVals(const std::pair<llvm::APSInt, CaseStmt*>& lhs,
527 const std::pair<llvm::APSInt, CaseStmt*>& rhs) {
528 if (lhs.first < rhs.first)
531 if (lhs.first == rhs.first &&
532 lhs.second->getCaseLoc().getRawEncoding()
533 < rhs.second->getCaseLoc().getRawEncoding())
538 /// CmpEnumVals - Comparison predicate for sorting enumeration values.
540 static bool CmpEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs,
541 const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs)
543 return lhs.first < rhs.first;
546 /// EqEnumVals - Comparison preficate for uniqing enumeration values.
548 static bool EqEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs,
549 const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs)
551 return lhs.first == rhs.first;
554 /// GetTypeBeforeIntegralPromotion - Returns the pre-promotion type of
555 /// potentially integral-promoted expression @p expr.
556 static QualType GetTypeBeforeIntegralPromotion(Expr *&expr) {
557 if (ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(expr))
558 expr = cleanups->getSubExpr();
559 while (ImplicitCastExpr *impcast = dyn_cast<ImplicitCastExpr>(expr)) {
560 if (impcast->getCastKind() != CK_IntegralCast) break;
561 expr = impcast->getSubExpr();
563 return expr->getType();
567 Sema::ActOnStartOfSwitchStmt(SourceLocation SwitchLoc, Expr *Cond,
569 ExprResult CondResult;
571 VarDecl *ConditionVar = 0;
573 ConditionVar = cast<VarDecl>(CondVar);
574 CondResult = CheckConditionVariable(ConditionVar, SourceLocation(), false);
575 if (CondResult.isInvalid())
578 Cond = CondResult.release();
584 class SwitchConvertDiagnoser : public ICEConvertDiagnoser {
588 SwitchConvertDiagnoser(Expr *Cond)
589 : ICEConvertDiagnoser(/*AllowScopedEnumerations*/true, false, true),
592 virtual SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
594 return S.Diag(Loc, diag::err_typecheck_statement_requires_integer) << T;
597 virtual SemaDiagnosticBuilder diagnoseIncomplete(
598 Sema &S, SourceLocation Loc, QualType T) {
599 return S.Diag(Loc, diag::err_switch_incomplete_class_type)
600 << T << Cond->getSourceRange();
603 virtual SemaDiagnosticBuilder diagnoseExplicitConv(
604 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) {
605 return S.Diag(Loc, diag::err_switch_explicit_conversion) << T << ConvTy;
608 virtual SemaDiagnosticBuilder noteExplicitConv(
609 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) {
610 return S.Diag(Conv->getLocation(), diag::note_switch_conversion)
611 << ConvTy->isEnumeralType() << ConvTy;
614 virtual SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
616 return S.Diag(Loc, diag::err_switch_multiple_conversions) << T;
619 virtual SemaDiagnosticBuilder noteAmbiguous(
620 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) {
621 return S.Diag(Conv->getLocation(), diag::note_switch_conversion)
622 << ConvTy->isEnumeralType() << ConvTy;
625 virtual SemaDiagnosticBuilder diagnoseConversion(
626 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) {
627 llvm_unreachable("conversion functions are permitted");
629 } SwitchDiagnoser(Cond);
632 PerformContextualImplicitConversion(SwitchLoc, Cond, SwitchDiagnoser);
633 if (CondResult.isInvalid()) return StmtError();
634 Cond = CondResult.take();
636 // C99 6.8.4.2p5 - Integer promotions are performed on the controlling expr.
637 CondResult = UsualUnaryConversions(Cond);
638 if (CondResult.isInvalid()) return StmtError();
639 Cond = CondResult.take();
642 CondResult = ActOnFinishFullExpr(Cond, SwitchLoc);
643 if (CondResult.isInvalid())
645 Cond = CondResult.take();
648 getCurFunction()->setHasBranchIntoScope();
650 SwitchStmt *SS = new (Context) SwitchStmt(Context, ConditionVar, Cond);
651 getCurFunction()->SwitchStack.push_back(SS);
655 static void AdjustAPSInt(llvm::APSInt &Val, unsigned BitWidth, bool IsSigned) {
656 if (Val.getBitWidth() < BitWidth)
657 Val = Val.extend(BitWidth);
658 else if (Val.getBitWidth() > BitWidth)
659 Val = Val.trunc(BitWidth);
660 Val.setIsSigned(IsSigned);
664 Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, Stmt *Switch,
666 SwitchStmt *SS = cast<SwitchStmt>(Switch);
667 assert(SS == getCurFunction()->SwitchStack.back() &&
668 "switch stack missing push/pop!");
670 SS->setBody(BodyStmt, SwitchLoc);
671 getCurFunction()->SwitchStack.pop_back();
673 Expr *CondExpr = SS->getCond();
674 if (!CondExpr) return StmtError();
676 QualType CondType = CondExpr->getType();
678 Expr *CondExprBeforePromotion = CondExpr;
679 QualType CondTypeBeforePromotion =
680 GetTypeBeforeIntegralPromotion(CondExprBeforePromotion);
683 // Integral promotions are performed (on the switch condition).
685 // A case value unrepresentable by the original switch condition
686 // type (before the promotion) doesn't make sense, even when it can
687 // be represented by the promoted type. Therefore we need to find
688 // the pre-promotion type of the switch condition.
689 if (!CondExpr->isTypeDependent()) {
690 // We have already converted the expression to an integral or enumeration
691 // type, when we started the switch statement. If we don't have an
692 // appropriate type now, just return an error.
693 if (!CondType->isIntegralOrEnumerationType())
696 if (CondExpr->isKnownToHaveBooleanValue()) {
697 // switch(bool_expr) {...} is often a programmer error, e.g.
698 // switch(n && mask) { ... } // Doh - should be "n & mask".
699 // One can always use an if statement instead of switch(bool_expr).
700 Diag(SwitchLoc, diag::warn_bool_switch_condition)
701 << CondExpr->getSourceRange();
705 // Get the bitwidth of the switched-on value before promotions. We must
706 // convert the integer case values to this width before comparison.
707 bool HasDependentValue
708 = CondExpr->isTypeDependent() || CondExpr->isValueDependent();
710 = HasDependentValue ? 0 : Context.getIntWidth(CondTypeBeforePromotion);
712 = CondTypeBeforePromotion->isSignedIntegerOrEnumerationType();
714 // Accumulate all of the case values in a vector so that we can sort them
715 // and detect duplicates. This vector contains the APInt for the case after
716 // it has been converted to the condition type.
717 typedef SmallVector<std::pair<llvm::APSInt, CaseStmt*>, 64> CaseValsTy;
720 // Keep track of any GNU case ranges we see. The APSInt is the low value.
721 typedef std::vector<std::pair<llvm::APSInt, CaseStmt*> > CaseRangesTy;
722 CaseRangesTy CaseRanges;
724 DefaultStmt *TheDefaultStmt = 0;
726 bool CaseListIsErroneous = false;
728 for (SwitchCase *SC = SS->getSwitchCaseList(); SC && !HasDependentValue;
729 SC = SC->getNextSwitchCase()) {
731 if (DefaultStmt *DS = dyn_cast<DefaultStmt>(SC)) {
732 if (TheDefaultStmt) {
733 Diag(DS->getDefaultLoc(), diag::err_multiple_default_labels_defined);
734 Diag(TheDefaultStmt->getDefaultLoc(), diag::note_duplicate_case_prev);
736 // FIXME: Remove the default statement from the switch block so that
737 // we'll return a valid AST. This requires recursing down the AST and
738 // finding it, not something we are set up to do right now. For now,
739 // just lop the entire switch stmt out of the AST.
740 CaseListIsErroneous = true;
745 CaseStmt *CS = cast<CaseStmt>(SC);
747 Expr *Lo = CS->getLHS();
749 if (Lo->isTypeDependent() || Lo->isValueDependent()) {
750 HasDependentValue = true;
756 if (getLangOpts().CPlusPlus11) {
757 // C++11 [stmt.switch]p2: the constant-expression shall be a converted
758 // constant expression of the promoted type of the switch condition.
760 CheckConvertedConstantExpression(Lo, CondType, LoVal, CCEK_CaseValue);
761 if (ConvLo.isInvalid()) {
762 CaseListIsErroneous = true;
767 // We already verified that the expression has a i-c-e value (C99
768 // 6.8.4.2p3) - get that value now.
769 LoVal = Lo->EvaluateKnownConstInt(Context);
771 // If the LHS is not the same type as the condition, insert an implicit
773 Lo = DefaultLvalueConversion(Lo).take();
774 Lo = ImpCastExprToType(Lo, CondType, CK_IntegralCast).take();
777 // Convert the value to the same width/sign as the condition had prior to
778 // integral promotions.
780 // FIXME: This causes us to reject valid code:
781 // switch ((char)c) { case 256: case 0: return 0; }
782 // Here we claim there is a duplicated condition value, but there is not.
783 ConvertIntegerToTypeWarnOnOverflow(LoVal, CondWidth, CondIsSigned,
785 diag::warn_case_value_overflow);
789 // If this is a case range, remember it in CaseRanges, otherwise CaseVals.
791 if (CS->getRHS()->isTypeDependent() ||
792 CS->getRHS()->isValueDependent()) {
793 HasDependentValue = true;
796 CaseRanges.push_back(std::make_pair(LoVal, CS));
798 CaseVals.push_back(std::make_pair(LoVal, CS));
802 if (!HasDependentValue) {
803 // If we don't have a default statement, check whether the
804 // condition is constant.
805 llvm::APSInt ConstantCondValue;
806 bool HasConstantCond = false;
807 if (!HasDependentValue && !TheDefaultStmt) {
809 = CondExprBeforePromotion->EvaluateAsInt(ConstantCondValue, Context,
810 Expr::SE_AllowSideEffects);
811 assert(!HasConstantCond ||
812 (ConstantCondValue.getBitWidth() == CondWidth &&
813 ConstantCondValue.isSigned() == CondIsSigned));
815 bool ShouldCheckConstantCond = HasConstantCond;
817 // Sort all the scalar case values so we can easily detect duplicates.
818 std::stable_sort(CaseVals.begin(), CaseVals.end(), CmpCaseVals);
820 if (!CaseVals.empty()) {
821 for (unsigned i = 0, e = CaseVals.size(); i != e; ++i) {
822 if (ShouldCheckConstantCond &&
823 CaseVals[i].first == ConstantCondValue)
824 ShouldCheckConstantCond = false;
826 if (i != 0 && CaseVals[i].first == CaseVals[i-1].first) {
827 // If we have a duplicate, report it.
828 // First, determine if either case value has a name
829 StringRef PrevString, CurrString;
830 Expr *PrevCase = CaseVals[i-1].second->getLHS()->IgnoreParenCasts();
831 Expr *CurrCase = CaseVals[i].second->getLHS()->IgnoreParenCasts();
832 if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(PrevCase)) {
833 PrevString = DeclRef->getDecl()->getName();
835 if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(CurrCase)) {
836 CurrString = DeclRef->getDecl()->getName();
838 SmallString<16> CaseValStr;
839 CaseVals[i-1].first.toString(CaseValStr);
841 if (PrevString == CurrString)
842 Diag(CaseVals[i].second->getLHS()->getLocStart(),
843 diag::err_duplicate_case) <<
844 (PrevString.empty() ? CaseValStr.str() : PrevString);
846 Diag(CaseVals[i].second->getLHS()->getLocStart(),
847 diag::err_duplicate_case_differing_expr) <<
848 (PrevString.empty() ? CaseValStr.str() : PrevString) <<
849 (CurrString.empty() ? CaseValStr.str() : CurrString) <<
852 Diag(CaseVals[i-1].second->getLHS()->getLocStart(),
853 diag::note_duplicate_case_prev);
854 // FIXME: We really want to remove the bogus case stmt from the
855 // substmt, but we have no way to do this right now.
856 CaseListIsErroneous = true;
861 // Detect duplicate case ranges, which usually don't exist at all in
863 if (!CaseRanges.empty()) {
864 // Sort all the case ranges by their low value so we can easily detect
865 // overlaps between ranges.
866 std::stable_sort(CaseRanges.begin(), CaseRanges.end());
868 // Scan the ranges, computing the high values and removing empty ranges.
869 std::vector<llvm::APSInt> HiVals;
870 for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) {
871 llvm::APSInt &LoVal = CaseRanges[i].first;
872 CaseStmt *CR = CaseRanges[i].second;
873 Expr *Hi = CR->getRHS();
876 if (getLangOpts().CPlusPlus11) {
877 // C++11 [stmt.switch]p2: the constant-expression shall be a converted
878 // constant expression of the promoted type of the switch condition.
880 CheckConvertedConstantExpression(Hi, CondType, HiVal,
882 if (ConvHi.isInvalid()) {
883 CaseListIsErroneous = true;
888 HiVal = Hi->EvaluateKnownConstInt(Context);
890 // If the RHS is not the same type as the condition, insert an
892 Hi = DefaultLvalueConversion(Hi).take();
893 Hi = ImpCastExprToType(Hi, CondType, CK_IntegralCast).take();
896 // Convert the value to the same width/sign as the condition.
897 ConvertIntegerToTypeWarnOnOverflow(HiVal, CondWidth, CondIsSigned,
899 diag::warn_case_value_overflow);
903 // If the low value is bigger than the high value, the case is empty.
905 Diag(CR->getLHS()->getLocStart(), diag::warn_case_empty_range)
906 << SourceRange(CR->getLHS()->getLocStart(),
908 CaseRanges.erase(CaseRanges.begin()+i);
913 if (ShouldCheckConstantCond &&
914 LoVal <= ConstantCondValue &&
915 ConstantCondValue <= HiVal)
916 ShouldCheckConstantCond = false;
918 HiVals.push_back(HiVal);
921 // Rescan the ranges, looking for overlap with singleton values and other
922 // ranges. Since the range list is sorted, we only need to compare case
923 // ranges with their neighbors.
924 for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) {
925 llvm::APSInt &CRLo = CaseRanges[i].first;
926 llvm::APSInt &CRHi = HiVals[i];
927 CaseStmt *CR = CaseRanges[i].second;
929 // Check to see whether the case range overlaps with any
931 CaseStmt *OverlapStmt = 0;
932 llvm::APSInt OverlapVal(32);
934 // Find the smallest value >= the lower bound. If I is in the
935 // case range, then we have overlap.
936 CaseValsTy::iterator I = std::lower_bound(CaseVals.begin(),
937 CaseVals.end(), CRLo,
938 CaseCompareFunctor());
939 if (I != CaseVals.end() && I->first < CRHi) {
940 OverlapVal = I->first; // Found overlap with scalar.
941 OverlapStmt = I->second;
944 // Find the smallest value bigger than the upper bound.
945 I = std::upper_bound(I, CaseVals.end(), CRHi, CaseCompareFunctor());
946 if (I != CaseVals.begin() && (I-1)->first >= CRLo) {
947 OverlapVal = (I-1)->first; // Found overlap with scalar.
948 OverlapStmt = (I-1)->second;
951 // Check to see if this case stmt overlaps with the subsequent
953 if (i && CRLo <= HiVals[i-1]) {
954 OverlapVal = HiVals[i-1]; // Found overlap with range.
955 OverlapStmt = CaseRanges[i-1].second;
959 // If we have a duplicate, report it.
960 Diag(CR->getLHS()->getLocStart(), diag::err_duplicate_case)
961 << OverlapVal.toString(10);
962 Diag(OverlapStmt->getLHS()->getLocStart(),
963 diag::note_duplicate_case_prev);
964 // FIXME: We really want to remove the bogus case stmt from the
965 // substmt, but we have no way to do this right now.
966 CaseListIsErroneous = true;
971 // Complain if we have a constant condition and we didn't find a match.
972 if (!CaseListIsErroneous && ShouldCheckConstantCond) {
973 // TODO: it would be nice if we printed enums as enums, chars as
975 Diag(CondExpr->getExprLoc(), diag::warn_missing_case_for_condition)
976 << ConstantCondValue.toString(10)
977 << CondExpr->getSourceRange();
980 // Check to see if switch is over an Enum and handles all of its
981 // values. We only issue a warning if there is not 'default:', but
982 // we still do the analysis to preserve this information in the AST
983 // (which can be used by flow-based analyes).
985 const EnumType *ET = CondTypeBeforePromotion->getAs<EnumType>();
987 // If switch has default case, then ignore it.
988 if (!CaseListIsErroneous && !HasConstantCond && ET) {
989 const EnumDecl *ED = ET->getDecl();
990 typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl*>, 64>
994 // Gather all enum values, set their type and sort them,
995 // allowing easier comparison with CaseVals.
996 for (EnumDecl::enumerator_iterator EDI = ED->enumerator_begin();
997 EDI != ED->enumerator_end(); ++EDI) {
998 llvm::APSInt Val = EDI->getInitVal();
999 AdjustAPSInt(Val, CondWidth, CondIsSigned);
1000 EnumVals.push_back(std::make_pair(Val, *EDI));
1002 std::stable_sort(EnumVals.begin(), EnumVals.end(), CmpEnumVals);
1003 EnumValsTy::iterator EIend =
1004 std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals);
1006 // See which case values aren't in enum.
1007 EnumValsTy::const_iterator EI = EnumVals.begin();
1008 for (CaseValsTy::const_iterator CI = CaseVals.begin();
1009 CI != CaseVals.end(); CI++) {
1010 while (EI != EIend && EI->first < CI->first)
1012 if (EI == EIend || EI->first > CI->first)
1013 Diag(CI->second->getLHS()->getExprLoc(), diag::warn_not_in_enum)
1014 << CondTypeBeforePromotion;
1016 // See which of case ranges aren't in enum
1017 EI = EnumVals.begin();
1018 for (CaseRangesTy::const_iterator RI = CaseRanges.begin();
1019 RI != CaseRanges.end() && EI != EIend; RI++) {
1020 while (EI != EIend && EI->first < RI->first)
1023 if (EI == EIend || EI->first != RI->first) {
1024 Diag(RI->second->getLHS()->getExprLoc(), diag::warn_not_in_enum)
1025 << CondTypeBeforePromotion;
1029 RI->second->getRHS()->EvaluateKnownConstInt(Context);
1030 AdjustAPSInt(Hi, CondWidth, CondIsSigned);
1031 while (EI != EIend && EI->first < Hi)
1033 if (EI == EIend || EI->first != Hi)
1034 Diag(RI->second->getRHS()->getExprLoc(), diag::warn_not_in_enum)
1035 << CondTypeBeforePromotion;
1038 // Check which enum vals aren't in switch
1039 CaseValsTy::const_iterator CI = CaseVals.begin();
1040 CaseRangesTy::const_iterator RI = CaseRanges.begin();
1041 bool hasCasesNotInSwitch = false;
1043 SmallVector<DeclarationName,8> UnhandledNames;
1045 for (EI = EnumVals.begin(); EI != EIend; EI++){
1046 // Drop unneeded case values
1048 while (CI != CaseVals.end() && CI->first < EI->first)
1051 if (CI != CaseVals.end() && CI->first == EI->first)
1054 // Drop unneeded case ranges
1055 for (; RI != CaseRanges.end(); RI++) {
1057 RI->second->getRHS()->EvaluateKnownConstInt(Context);
1058 AdjustAPSInt(Hi, CondWidth, CondIsSigned);
1059 if (EI->first <= Hi)
1063 if (RI == CaseRanges.end() || EI->first < RI->first) {
1064 hasCasesNotInSwitch = true;
1065 UnhandledNames.push_back(EI->second->getDeclName());
1069 if (TheDefaultStmt && UnhandledNames.empty())
1070 Diag(TheDefaultStmt->getDefaultLoc(), diag::warn_unreachable_default);
1072 // Produce a nice diagnostic if multiple values aren't handled.
1073 switch (UnhandledNames.size()) {
1076 Diag(CondExpr->getExprLoc(), TheDefaultStmt
1077 ? diag::warn_def_missing_case1 : diag::warn_missing_case1)
1078 << UnhandledNames[0];
1081 Diag(CondExpr->getExprLoc(), TheDefaultStmt
1082 ? diag::warn_def_missing_case2 : diag::warn_missing_case2)
1083 << UnhandledNames[0] << UnhandledNames[1];
1086 Diag(CondExpr->getExprLoc(), TheDefaultStmt
1087 ? diag::warn_def_missing_case3 : diag::warn_missing_case3)
1088 << UnhandledNames[0] << UnhandledNames[1] << UnhandledNames[2];
1091 Diag(CondExpr->getExprLoc(), TheDefaultStmt
1092 ? diag::warn_def_missing_cases : diag::warn_missing_cases)
1093 << (unsigned)UnhandledNames.size()
1094 << UnhandledNames[0] << UnhandledNames[1] << UnhandledNames[2];
1098 if (!hasCasesNotInSwitch)
1099 SS->setAllEnumCasesCovered();
1103 DiagnoseEmptyStmtBody(CondExpr->getLocEnd(), BodyStmt,
1104 diag::warn_empty_switch_body);
1106 // FIXME: If the case list was broken is some way, we don't have a good system
1107 // to patch it up. Instead, just return the whole substmt as broken.
1108 if (CaseListIsErroneous)
1115 Sema::DiagnoseAssignmentEnum(QualType DstType, QualType SrcType,
1117 if (Diags.getDiagnosticLevel(diag::warn_not_in_enum_assignment,
1118 SrcExpr->getExprLoc()) ==
1119 DiagnosticsEngine::Ignored)
1122 if (const EnumType *ET = DstType->getAs<EnumType>())
1123 if (!Context.hasSameType(SrcType, DstType) &&
1124 SrcType->isIntegerType()) {
1125 if (!SrcExpr->isTypeDependent() && !SrcExpr->isValueDependent() &&
1126 SrcExpr->isIntegerConstantExpr(Context)) {
1127 // Get the bitwidth of the enum value before promotions.
1128 unsigned DstWidth = Context.getIntWidth(DstType);
1129 bool DstIsSigned = DstType->isSignedIntegerOrEnumerationType();
1131 llvm::APSInt RhsVal = SrcExpr->EvaluateKnownConstInt(Context);
1132 AdjustAPSInt(RhsVal, DstWidth, DstIsSigned);
1133 const EnumDecl *ED = ET->getDecl();
1134 typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl *>, 64>
1136 EnumValsTy EnumVals;
1138 // Gather all enum values, set their type and sort them,
1139 // allowing easier comparison with rhs constant.
1140 for (EnumDecl::enumerator_iterator EDI = ED->enumerator_begin();
1141 EDI != ED->enumerator_end(); ++EDI) {
1142 llvm::APSInt Val = EDI->getInitVal();
1143 AdjustAPSInt(Val, DstWidth, DstIsSigned);
1144 EnumVals.push_back(std::make_pair(Val, *EDI));
1146 if (EnumVals.empty())
1148 std::stable_sort(EnumVals.begin(), EnumVals.end(), CmpEnumVals);
1149 EnumValsTy::iterator EIend =
1150 std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals);
1152 // See which values aren't in the enum.
1153 EnumValsTy::const_iterator EI = EnumVals.begin();
1154 while (EI != EIend && EI->first < RhsVal)
1156 if (EI == EIend || EI->first != RhsVal) {
1157 Diag(SrcExpr->getExprLoc(), diag::warn_not_in_enum_assignment)
1165 Sema::ActOnWhileStmt(SourceLocation WhileLoc, FullExprArg Cond,
1166 Decl *CondVar, Stmt *Body) {
1167 ExprResult CondResult(Cond.release());
1169 VarDecl *ConditionVar = 0;
1171 ConditionVar = cast<VarDecl>(CondVar);
1172 CondResult = CheckConditionVariable(ConditionVar, WhileLoc, true);
1173 if (CondResult.isInvalid())
1176 Expr *ConditionExpr = CondResult.take();
1180 DiagnoseUnusedExprResult(Body);
1182 if (isa<NullStmt>(Body))
1183 getCurCompoundScope().setHasEmptyLoopBodies();
1185 return Owned(new (Context) WhileStmt(Context, ConditionVar, ConditionExpr,
1190 Sema::ActOnDoStmt(SourceLocation DoLoc, Stmt *Body,
1191 SourceLocation WhileLoc, SourceLocation CondLParen,
1192 Expr *Cond, SourceLocation CondRParen) {
1193 assert(Cond && "ActOnDoStmt(): missing expression");
1195 ExprResult CondResult = CheckBooleanCondition(Cond, DoLoc);
1196 if (CondResult.isInvalid())
1198 Cond = CondResult.take();
1200 CondResult = ActOnFinishFullExpr(Cond, DoLoc);
1201 if (CondResult.isInvalid())
1203 Cond = CondResult.take();
1205 DiagnoseUnusedExprResult(Body);
1207 return Owned(new (Context) DoStmt(Body, Cond, DoLoc, WhileLoc, CondRParen));
1211 // This visitor will traverse a conditional statement and store all
1212 // the evaluated decls into a vector. Simple is set to true if none
1213 // of the excluded constructs are used.
1214 class DeclExtractor : public EvaluatedExprVisitor<DeclExtractor> {
1215 llvm::SmallPtrSet<VarDecl*, 8> &Decls;
1216 SmallVectorImpl<SourceRange> &Ranges;
1219 typedef EvaluatedExprVisitor<DeclExtractor> Inherited;
1221 DeclExtractor(Sema &S, llvm::SmallPtrSet<VarDecl*, 8> &Decls,
1222 SmallVectorImpl<SourceRange> &Ranges) :
1223 Inherited(S.Context),
1228 bool isSimple() { return Simple; }
1230 // Replaces the method in EvaluatedExprVisitor.
1231 void VisitMemberExpr(MemberExpr* E) {
1235 // Any Stmt not whitelisted will cause the condition to be marked complex.
1236 void VisitStmt(Stmt *S) {
1240 void VisitBinaryOperator(BinaryOperator *E) {
1245 void VisitCastExpr(CastExpr *E) {
1246 Visit(E->getSubExpr());
1249 void VisitUnaryOperator(UnaryOperator *E) {
1250 // Skip checking conditionals with derefernces.
1251 if (E->getOpcode() == UO_Deref)
1254 Visit(E->getSubExpr());
1257 void VisitConditionalOperator(ConditionalOperator *E) {
1258 Visit(E->getCond());
1259 Visit(E->getTrueExpr());
1260 Visit(E->getFalseExpr());
1263 void VisitParenExpr(ParenExpr *E) {
1264 Visit(E->getSubExpr());
1267 void VisitBinaryConditionalOperator(BinaryConditionalOperator *E) {
1268 Visit(E->getOpaqueValue()->getSourceExpr());
1269 Visit(E->getFalseExpr());
1272 void VisitIntegerLiteral(IntegerLiteral *E) { }
1273 void VisitFloatingLiteral(FloatingLiteral *E) { }
1274 void VisitCXXBoolLiteralExpr(CXXBoolLiteralExpr *E) { }
1275 void VisitCharacterLiteral(CharacterLiteral *E) { }
1276 void VisitGNUNullExpr(GNUNullExpr *E) { }
1277 void VisitImaginaryLiteral(ImaginaryLiteral *E) { }
1279 void VisitDeclRefExpr(DeclRefExpr *E) {
1280 VarDecl *VD = dyn_cast<VarDecl>(E->getDecl());
1283 Ranges.push_back(E->getSourceRange());
1288 }; // end class DeclExtractor
1290 // DeclMatcher checks to see if the decls are used in a non-evauluated
1292 class DeclMatcher : public EvaluatedExprVisitor<DeclMatcher> {
1293 llvm::SmallPtrSet<VarDecl*, 8> &Decls;
1297 typedef EvaluatedExprVisitor<DeclMatcher> Inherited;
1299 DeclMatcher(Sema &S, llvm::SmallPtrSet<VarDecl*, 8> &Decls,
1301 Inherited(S.Context), Decls(Decls), FoundDecl(false) {
1302 if (!Statement) return;
1307 void VisitReturnStmt(ReturnStmt *S) {
1311 void VisitBreakStmt(BreakStmt *S) {
1315 void VisitGotoStmt(GotoStmt *S) {
1319 void VisitCastExpr(CastExpr *E) {
1320 if (E->getCastKind() == CK_LValueToRValue)
1321 CheckLValueToRValueCast(E->getSubExpr());
1323 Visit(E->getSubExpr());
1326 void CheckLValueToRValueCast(Expr *E) {
1327 E = E->IgnoreParenImpCasts();
1329 if (isa<DeclRefExpr>(E)) {
1333 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
1334 Visit(CO->getCond());
1335 CheckLValueToRValueCast(CO->getTrueExpr());
1336 CheckLValueToRValueCast(CO->getFalseExpr());
1340 if (BinaryConditionalOperator *BCO =
1341 dyn_cast<BinaryConditionalOperator>(E)) {
1342 CheckLValueToRValueCast(BCO->getOpaqueValue()->getSourceExpr());
1343 CheckLValueToRValueCast(BCO->getFalseExpr());
1350 void VisitDeclRefExpr(DeclRefExpr *E) {
1351 if (VarDecl *VD = dyn_cast<VarDecl>(E->getDecl()))
1352 if (Decls.count(VD))
1356 bool FoundDeclInUse() { return FoundDecl; }
1358 }; // end class DeclMatcher
1360 void CheckForLoopConditionalStatement(Sema &S, Expr *Second,
1361 Expr *Third, Stmt *Body) {
1362 // Condition is empty
1363 if (!Second) return;
1365 if (S.Diags.getDiagnosticLevel(diag::warn_variables_not_in_loop_body,
1366 Second->getLocStart())
1367 == DiagnosticsEngine::Ignored)
1370 PartialDiagnostic PDiag = S.PDiag(diag::warn_variables_not_in_loop_body);
1371 llvm::SmallPtrSet<VarDecl*, 8> Decls;
1372 SmallVector<SourceRange, 10> Ranges;
1373 DeclExtractor DE(S, Decls, Ranges);
1376 // Don't analyze complex conditionals.
1377 if (!DE.isSimple()) return;
1380 if (Decls.size() == 0) return;
1382 // Don't warn on volatile, static, or global variables.
1383 for (llvm::SmallPtrSet<VarDecl*, 8>::iterator I = Decls.begin(),
1386 if ((*I)->getType().isVolatileQualified() ||
1387 (*I)->hasGlobalStorage()) return;
1389 if (DeclMatcher(S, Decls, Second).FoundDeclInUse() ||
1390 DeclMatcher(S, Decls, Third).FoundDeclInUse() ||
1391 DeclMatcher(S, Decls, Body).FoundDeclInUse())
1394 // Load decl names into diagnostic.
1395 if (Decls.size() > 4)
1398 PDiag << Decls.size();
1399 for (llvm::SmallPtrSet<VarDecl*, 8>::iterator I = Decls.begin(),
1402 PDiag << (*I)->getDeclName();
1405 // Load SourceRanges into diagnostic if there is room.
1406 // Otherwise, load the SourceRange of the conditional expression.
1407 if (Ranges.size() <= PartialDiagnostic::MaxArguments)
1408 for (SmallVectorImpl<SourceRange>::iterator I = Ranges.begin(),
1413 PDiag << Second->getSourceRange();
1415 S.Diag(Ranges.begin()->getBegin(), PDiag);
1418 // If Statement is an incemement or decrement, return true and sets the
1419 // variables Increment and DRE.
1420 bool ProcessIterationStmt(Sema &S, Stmt* Statement, bool &Increment,
1421 DeclRefExpr *&DRE) {
1422 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(Statement)) {
1423 switch (UO->getOpcode()) {
1424 default: return false;
1434 DRE = dyn_cast<DeclRefExpr>(UO->getSubExpr());
1438 if (CXXOperatorCallExpr *Call = dyn_cast<CXXOperatorCallExpr>(Statement)) {
1439 FunctionDecl *FD = Call->getDirectCallee();
1440 if (!FD || !FD->isOverloadedOperator()) return false;
1441 switch (FD->getOverloadedOperator()) {
1442 default: return false;
1450 DRE = dyn_cast<DeclRefExpr>(Call->getArg(0));
1457 // A visitor to determine if a continue statement is a subexpression.
1458 class ContinueFinder : public EvaluatedExprVisitor<ContinueFinder> {
1461 ContinueFinder(Sema &S, Stmt* Body) :
1462 Inherited(S.Context),
1467 typedef EvaluatedExprVisitor<ContinueFinder> Inherited;
1469 void VisitContinueStmt(ContinueStmt* E) {
1473 bool ContinueFound() { return Found; }
1475 }; // end class ContinueFinder
1477 // Emit a warning when a loop increment/decrement appears twice per loop
1478 // iteration. The conditions which trigger this warning are:
1479 // 1) The last statement in the loop body and the third expression in the
1480 // for loop are both increment or both decrement of the same variable
1481 // 2) No continue statements in the loop body.
1482 void CheckForRedundantIteration(Sema &S, Expr *Third, Stmt *Body) {
1483 // Return when there is nothing to check.
1484 if (!Body || !Third) return;
1486 if (S.Diags.getDiagnosticLevel(diag::warn_redundant_loop_iteration,
1487 Third->getLocStart())
1488 == DiagnosticsEngine::Ignored)
1491 // Get the last statement from the loop body.
1492 CompoundStmt *CS = dyn_cast<CompoundStmt>(Body);
1493 if (!CS || CS->body_empty()) return;
1494 Stmt *LastStmt = CS->body_back();
1495 if (!LastStmt) return;
1497 bool LoopIncrement, LastIncrement;
1498 DeclRefExpr *LoopDRE, *LastDRE;
1500 if (!ProcessIterationStmt(S, Third, LoopIncrement, LoopDRE)) return;
1501 if (!ProcessIterationStmt(S, LastStmt, LastIncrement, LastDRE)) return;
1503 // Check that the two statements are both increments or both decrements
1504 // on the same varaible.
1505 if (LoopIncrement != LastIncrement ||
1506 LoopDRE->getDecl() != LastDRE->getDecl()) return;
1508 if (ContinueFinder(S, Body).ContinueFound()) return;
1510 S.Diag(LastDRE->getLocation(), diag::warn_redundant_loop_iteration)
1511 << LastDRE->getDecl() << LastIncrement;
1512 S.Diag(LoopDRE->getLocation(), diag::note_loop_iteration_here)
1519 Sema::ActOnForStmt(SourceLocation ForLoc, SourceLocation LParenLoc,
1520 Stmt *First, FullExprArg second, Decl *secondVar,
1522 SourceLocation RParenLoc, Stmt *Body) {
1523 if (!getLangOpts().CPlusPlus) {
1524 if (DeclStmt *DS = dyn_cast_or_null<DeclStmt>(First)) {
1525 // C99 6.8.5p3: The declaration part of a 'for' statement shall only
1526 // declare identifiers for objects having storage class 'auto' or
1528 for (DeclStmt::decl_iterator DI=DS->decl_begin(), DE=DS->decl_end();
1530 VarDecl *VD = dyn_cast<VarDecl>(*DI);
1531 if (VD && VD->isLocalVarDecl() && !VD->hasLocalStorage())
1534 Diag((*DI)->getLocation(), diag::err_non_local_variable_decl_in_for);
1535 (*DI)->setInvalidDecl();
1541 CheckForLoopConditionalStatement(*this, second.get(), third.get(), Body);
1542 CheckForRedundantIteration(*this, third.get(), Body);
1544 ExprResult SecondResult(second.release());
1545 VarDecl *ConditionVar = 0;
1547 ConditionVar = cast<VarDecl>(secondVar);
1548 SecondResult = CheckConditionVariable(ConditionVar, ForLoc, true);
1549 if (SecondResult.isInvalid())
1553 Expr *Third = third.release().takeAs<Expr>();
1555 DiagnoseUnusedExprResult(First);
1556 DiagnoseUnusedExprResult(Third);
1557 DiagnoseUnusedExprResult(Body);
1559 if (isa<NullStmt>(Body))
1560 getCurCompoundScope().setHasEmptyLoopBodies();
1562 return Owned(new (Context) ForStmt(Context, First,
1563 SecondResult.take(), ConditionVar,
1564 Third, Body, ForLoc, LParenLoc,
1568 /// In an Objective C collection iteration statement:
1570 /// x can be an arbitrary l-value expression. Bind it up as a
1571 /// full-expression.
1572 StmtResult Sema::ActOnForEachLValueExpr(Expr *E) {
1573 // Reduce placeholder expressions here. Note that this rejects the
1574 // use of pseudo-object l-values in this position.
1575 ExprResult result = CheckPlaceholderExpr(E);
1576 if (result.isInvalid()) return StmtError();
1579 ExprResult FullExpr = ActOnFinishFullExpr(E);
1580 if (FullExpr.isInvalid())
1582 return StmtResult(static_cast<Stmt*>(FullExpr.take()));
1586 Sema::CheckObjCForCollectionOperand(SourceLocation forLoc, Expr *collection) {
1590 // Bail out early if we've got a type-dependent expression.
1591 if (collection->isTypeDependent()) return Owned(collection);
1593 // Perform normal l-value conversion.
1594 ExprResult result = DefaultFunctionArrayLvalueConversion(collection);
1595 if (result.isInvalid())
1597 collection = result.take();
1599 // The operand needs to have object-pointer type.
1600 // TODO: should we do a contextual conversion?
1601 const ObjCObjectPointerType *pointerType =
1602 collection->getType()->getAs<ObjCObjectPointerType>();
1604 return Diag(forLoc, diag::err_collection_expr_type)
1605 << collection->getType() << collection->getSourceRange();
1607 // Check that the operand provides
1608 // - countByEnumeratingWithState:objects:count:
1609 const ObjCObjectType *objectType = pointerType->getObjectType();
1610 ObjCInterfaceDecl *iface = objectType->getInterface();
1612 // If we have a forward-declared type, we can't do this check.
1613 // Under ARC, it is an error not to have a forward-declared class.
1615 RequireCompleteType(forLoc, QualType(objectType, 0),
1616 getLangOpts().ObjCAutoRefCount
1617 ? diag::err_arc_collection_forward
1620 // Otherwise, if we have any useful type information, check that
1621 // the type declares the appropriate method.
1622 } else if (iface || !objectType->qual_empty()) {
1623 IdentifierInfo *selectorIdents[] = {
1624 &Context.Idents.get("countByEnumeratingWithState"),
1625 &Context.Idents.get("objects"),
1626 &Context.Idents.get("count")
1628 Selector selector = Context.Selectors.getSelector(3, &selectorIdents[0]);
1630 ObjCMethodDecl *method = 0;
1632 // If there's an interface, look in both the public and private APIs.
1634 method = iface->lookupInstanceMethod(selector);
1635 if (!method) method = iface->lookupPrivateMethod(selector);
1638 // Also check protocol qualifiers.
1640 method = LookupMethodInQualifiedType(selector, pointerType,
1643 // If we didn't find it anywhere, give up.
1645 Diag(forLoc, diag::warn_collection_expr_type)
1646 << collection->getType() << selector << collection->getSourceRange();
1649 // TODO: check for an incompatible signature?
1652 // Wrap up any cleanups in the expression.
1653 return Owned(collection);
1657 Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc,
1658 Stmt *First, Expr *collection,
1659 SourceLocation RParenLoc) {
1661 ExprResult CollectionExprResult =
1662 CheckObjCForCollectionOperand(ForLoc, collection);
1666 if (DeclStmt *DS = dyn_cast<DeclStmt>(First)) {
1667 if (!DS->isSingleDecl())
1668 return StmtError(Diag((*DS->decl_begin())->getLocation(),
1669 diag::err_toomany_element_decls));
1671 VarDecl *D = dyn_cast<VarDecl>(DS->getSingleDecl());
1672 if (!D || D->isInvalidDecl())
1675 FirstType = D->getType();
1676 // C99 6.8.5p3: The declaration part of a 'for' statement shall only
1677 // declare identifiers for objects having storage class 'auto' or
1679 if (!D->hasLocalStorage())
1680 return StmtError(Diag(D->getLocation(),
1681 diag::err_non_local_variable_decl_in_for));
1683 // If the type contained 'auto', deduce the 'auto' to 'id'.
1684 if (FirstType->getContainedAutoType()) {
1685 OpaqueValueExpr OpaqueId(D->getLocation(), Context.getObjCIdType(),
1687 Expr *DeducedInit = &OpaqueId;
1688 if (DeduceAutoType(D->getTypeSourceInfo(), DeducedInit, FirstType) ==
1690 DiagnoseAutoDeductionFailure(D, DeducedInit);
1691 if (FirstType.isNull()) {
1692 D->setInvalidDecl();
1696 D->setType(FirstType);
1698 if (ActiveTemplateInstantiations.empty()) {
1699 SourceLocation Loc =
1700 D->getTypeSourceInfo()->getTypeLoc().getBeginLoc();
1701 Diag(Loc, diag::warn_auto_var_is_id)
1702 << D->getDeclName();
1707 Expr *FirstE = cast<Expr>(First);
1708 if (!FirstE->isTypeDependent() && !FirstE->isLValue())
1709 return StmtError(Diag(First->getLocStart(),
1710 diag::err_selector_element_not_lvalue)
1711 << First->getSourceRange());
1713 FirstType = static_cast<Expr*>(First)->getType();
1714 if (FirstType.isConstQualified())
1715 Diag(ForLoc, diag::err_selector_element_const_type)
1716 << FirstType << First->getSourceRange();
1718 if (!FirstType->isDependentType() &&
1719 !FirstType->isObjCObjectPointerType() &&
1720 !FirstType->isBlockPointerType())
1721 return StmtError(Diag(ForLoc, diag::err_selector_element_type)
1722 << FirstType << First->getSourceRange());
1725 if (CollectionExprResult.isInvalid())
1728 CollectionExprResult = ActOnFinishFullExpr(CollectionExprResult.take());
1729 if (CollectionExprResult.isInvalid())
1732 return Owned(new (Context) ObjCForCollectionStmt(First,
1733 CollectionExprResult.take(), 0,
1734 ForLoc, RParenLoc));
1737 /// Finish building a variable declaration for a for-range statement.
1738 /// \return true if an error occurs.
1739 static bool FinishForRangeVarDecl(Sema &SemaRef, VarDecl *Decl, Expr *Init,
1740 SourceLocation Loc, int DiagID) {
1741 // Deduce the type for the iterator variable now rather than leaving it to
1742 // AddInitializerToDecl, so we can produce a more suitable diagnostic.
1744 if ((!isa<InitListExpr>(Init) && Init->getType()->isVoidType()) ||
1745 SemaRef.DeduceAutoType(Decl->getTypeSourceInfo(), Init, InitType) ==
1747 SemaRef.Diag(Loc, DiagID) << Init->getType();
1748 if (InitType.isNull()) {
1749 Decl->setInvalidDecl();
1752 Decl->setType(InitType);
1754 // In ARC, infer lifetime.
1755 // FIXME: ARC may want to turn this into 'const __unsafe_unretained' if
1756 // we're doing the equivalent of fast iteration.
1757 if (SemaRef.getLangOpts().ObjCAutoRefCount &&
1758 SemaRef.inferObjCARCLifetime(Decl))
1759 Decl->setInvalidDecl();
1761 SemaRef.AddInitializerToDecl(Decl, Init, /*DirectInit=*/false,
1762 /*TypeMayContainAuto=*/false);
1763 SemaRef.FinalizeDeclaration(Decl);
1764 SemaRef.CurContext->addHiddenDecl(Decl);
1770 /// Produce a note indicating which begin/end function was implicitly called
1771 /// by a C++11 for-range statement. This is often not obvious from the code,
1772 /// nor from the diagnostics produced when analysing the implicit expressions
1773 /// required in a for-range statement.
1774 void NoteForRangeBeginEndFunction(Sema &SemaRef, Expr *E,
1775 Sema::BeginEndFunction BEF) {
1776 CallExpr *CE = dyn_cast<CallExpr>(E);
1779 FunctionDecl *D = dyn_cast<FunctionDecl>(CE->getCalleeDecl());
1782 SourceLocation Loc = D->getLocation();
1784 std::string Description;
1785 bool IsTemplate = false;
1786 if (FunctionTemplateDecl *FunTmpl = D->getPrimaryTemplate()) {
1787 Description = SemaRef.getTemplateArgumentBindingsText(
1788 FunTmpl->getTemplateParameters(), *D->getTemplateSpecializationArgs());
1792 SemaRef.Diag(Loc, diag::note_for_range_begin_end)
1793 << BEF << IsTemplate << Description << E->getType();
1796 /// Build a variable declaration for a for-range statement.
1797 VarDecl *BuildForRangeVarDecl(Sema &SemaRef, SourceLocation Loc,
1798 QualType Type, const char *Name) {
1799 DeclContext *DC = SemaRef.CurContext;
1800 IdentifierInfo *II = &SemaRef.PP.getIdentifierTable().get(Name);
1801 TypeSourceInfo *TInfo = SemaRef.Context.getTrivialTypeSourceInfo(Type, Loc);
1802 VarDecl *Decl = VarDecl::Create(SemaRef.Context, DC, Loc, Loc, II, Type,
1804 Decl->setImplicit();
1810 static bool ObjCEnumerationCollection(Expr *Collection) {
1811 return !Collection->isTypeDependent()
1812 && Collection->getType()->getAs<ObjCObjectPointerType>() != 0;
1815 /// ActOnCXXForRangeStmt - Check and build a C++11 for-range statement.
1817 /// C++11 [stmt.ranged]:
1818 /// A range-based for statement is equivalent to
1821 /// auto && __range = range-init;
1822 /// for ( auto __begin = begin-expr,
1823 /// __end = end-expr;
1824 /// __begin != __end;
1826 /// for-range-declaration = *__begin;
1831 /// The body of the loop is not available yet, since it cannot be analysed until
1832 /// we have determined the type of the for-range-declaration.
1834 Sema::ActOnCXXForRangeStmt(SourceLocation ForLoc,
1835 Stmt *First, SourceLocation ColonLoc, Expr *Range,
1836 SourceLocation RParenLoc, BuildForRangeKind Kind) {
1840 if (Range && ObjCEnumerationCollection(Range))
1841 return ActOnObjCForCollectionStmt(ForLoc, First, Range, RParenLoc);
1843 DeclStmt *DS = dyn_cast<DeclStmt>(First);
1844 assert(DS && "first part of for range not a decl stmt");
1846 if (!DS->isSingleDecl()) {
1847 Diag(DS->getStartLoc(), diag::err_type_defined_in_for_range);
1851 Decl *LoopVar = DS->getSingleDecl();
1852 if (LoopVar->isInvalidDecl() || !Range ||
1853 DiagnoseUnexpandedParameterPack(Range, UPPC_Expression)) {
1854 LoopVar->setInvalidDecl();
1858 // Build auto && __range = range-init
1859 SourceLocation RangeLoc = Range->getLocStart();
1860 VarDecl *RangeVar = BuildForRangeVarDecl(*this, RangeLoc,
1861 Context.getAutoRRefDeductType(),
1863 if (FinishForRangeVarDecl(*this, RangeVar, Range, RangeLoc,
1864 diag::err_for_range_deduction_failure)) {
1865 LoopVar->setInvalidDecl();
1869 // Claim the type doesn't contain auto: we've already done the checking.
1870 DeclGroupPtrTy RangeGroup =
1871 BuildDeclaratorGroup(llvm::MutableArrayRef<Decl *>((Decl **)&RangeVar, 1),
1872 /*TypeMayContainAuto=*/ false);
1873 StmtResult RangeDecl = ActOnDeclStmt(RangeGroup, RangeLoc, RangeLoc);
1874 if (RangeDecl.isInvalid()) {
1875 LoopVar->setInvalidDecl();
1879 return BuildCXXForRangeStmt(ForLoc, ColonLoc, RangeDecl.get(),
1880 /*BeginEndDecl=*/0, /*Cond=*/0, /*Inc=*/0, DS,
1884 /// \brief Create the initialization, compare, and increment steps for
1885 /// the range-based for loop expression.
1886 /// This function does not handle array-based for loops,
1887 /// which are created in Sema::BuildCXXForRangeStmt.
1889 /// \returns a ForRangeStatus indicating success or what kind of error occurred.
1890 /// BeginExpr and EndExpr are set and FRS_Success is returned on success;
1891 /// CandidateSet and BEF are set and some non-success value is returned on
1893 static Sema::ForRangeStatus BuildNonArrayForRange(Sema &SemaRef, Scope *S,
1894 Expr *BeginRange, Expr *EndRange,
1898 SourceLocation ColonLoc,
1899 OverloadCandidateSet *CandidateSet,
1900 ExprResult *BeginExpr,
1901 ExprResult *EndExpr,
1902 Sema::BeginEndFunction *BEF) {
1903 DeclarationNameInfo BeginNameInfo(
1904 &SemaRef.PP.getIdentifierTable().get("begin"), ColonLoc);
1905 DeclarationNameInfo EndNameInfo(&SemaRef.PP.getIdentifierTable().get("end"),
1908 LookupResult BeginMemberLookup(SemaRef, BeginNameInfo,
1909 Sema::LookupMemberName);
1910 LookupResult EndMemberLookup(SemaRef, EndNameInfo, Sema::LookupMemberName);
1912 if (CXXRecordDecl *D = RangeType->getAsCXXRecordDecl()) {
1913 // - if _RangeT is a class type, the unqualified-ids begin and end are
1914 // looked up in the scope of class _RangeT as if by class member access
1915 // lookup (3.4.5), and if either (or both) finds at least one
1916 // declaration, begin-expr and end-expr are __range.begin() and
1917 // __range.end(), respectively;
1918 SemaRef.LookupQualifiedName(BeginMemberLookup, D);
1919 SemaRef.LookupQualifiedName(EndMemberLookup, D);
1921 if (BeginMemberLookup.empty() != EndMemberLookup.empty()) {
1922 SourceLocation RangeLoc = BeginVar->getLocation();
1923 *BEF = BeginMemberLookup.empty() ? Sema::BEF_end : Sema::BEF_begin;
1925 SemaRef.Diag(RangeLoc, diag::err_for_range_member_begin_end_mismatch)
1926 << RangeLoc << BeginRange->getType() << *BEF;
1927 return Sema::FRS_DiagnosticIssued;
1930 // - otherwise, begin-expr and end-expr are begin(__range) and
1931 // end(__range), respectively, where begin and end are looked up with
1932 // argument-dependent lookup (3.4.2). For the purposes of this name
1933 // lookup, namespace std is an associated namespace.
1937 *BEF = Sema::BEF_begin;
1938 Sema::ForRangeStatus RangeStatus =
1939 SemaRef.BuildForRangeBeginEndCall(S, ColonLoc, ColonLoc, BeginVar,
1940 Sema::BEF_begin, BeginNameInfo,
1941 BeginMemberLookup, CandidateSet,
1942 BeginRange, BeginExpr);
1944 if (RangeStatus != Sema::FRS_Success)
1946 if (FinishForRangeVarDecl(SemaRef, BeginVar, BeginExpr->get(), ColonLoc,
1947 diag::err_for_range_iter_deduction_failure)) {
1948 NoteForRangeBeginEndFunction(SemaRef, BeginExpr->get(), *BEF);
1949 return Sema::FRS_DiagnosticIssued;
1952 *BEF = Sema::BEF_end;
1954 SemaRef.BuildForRangeBeginEndCall(S, ColonLoc, ColonLoc, EndVar,
1955 Sema::BEF_end, EndNameInfo,
1956 EndMemberLookup, CandidateSet,
1958 if (RangeStatus != Sema::FRS_Success)
1960 if (FinishForRangeVarDecl(SemaRef, EndVar, EndExpr->get(), ColonLoc,
1961 diag::err_for_range_iter_deduction_failure)) {
1962 NoteForRangeBeginEndFunction(SemaRef, EndExpr->get(), *BEF);
1963 return Sema::FRS_DiagnosticIssued;
1965 return Sema::FRS_Success;
1968 /// Speculatively attempt to dereference an invalid range expression.
1969 /// If the attempt fails, this function will return a valid, null StmtResult
1970 /// and emit no diagnostics.
1971 static StmtResult RebuildForRangeWithDereference(Sema &SemaRef, Scope *S,
1972 SourceLocation ForLoc,
1974 SourceLocation ColonLoc,
1976 SourceLocation RangeLoc,
1977 SourceLocation RParenLoc) {
1978 // Determine whether we can rebuild the for-range statement with a
1979 // dereferenced range expression.
1980 ExprResult AdjustedRange;
1982 Sema::SFINAETrap Trap(SemaRef);
1984 AdjustedRange = SemaRef.BuildUnaryOp(S, RangeLoc, UO_Deref, Range);
1985 if (AdjustedRange.isInvalid())
1986 return StmtResult();
1989 SemaRef.ActOnCXXForRangeStmt(ForLoc, LoopVarDecl, ColonLoc,
1990 AdjustedRange.get(), RParenLoc,
1993 return StmtResult();
1996 // The attempt to dereference worked well enough that it could produce a valid
1997 // loop. Produce a fixit, and rebuild the loop with diagnostics enabled, in
1998 // case there are any other (non-fatal) problems with it.
1999 SemaRef.Diag(RangeLoc, diag::err_for_range_dereference)
2000 << Range->getType() << FixItHint::CreateInsertion(RangeLoc, "*");
2001 return SemaRef.ActOnCXXForRangeStmt(ForLoc, LoopVarDecl, ColonLoc,
2002 AdjustedRange.get(), RParenLoc,
2003 Sema::BFRK_Rebuild);
2007 /// RAII object to automatically invalidate a declaration if an error occurs.
2008 struct InvalidateOnErrorScope {
2009 InvalidateOnErrorScope(Sema &SemaRef, Decl *D, bool Enabled)
2010 : Trap(SemaRef.Diags), D(D), Enabled(Enabled) {}
2011 ~InvalidateOnErrorScope() {
2012 if (Enabled && Trap.hasErrorOccurred())
2013 D->setInvalidDecl();
2016 DiagnosticErrorTrap Trap;
2022 /// BuildCXXForRangeStmt - Build or instantiate a C++11 for-range statement.
2024 Sema::BuildCXXForRangeStmt(SourceLocation ForLoc, SourceLocation ColonLoc,
2025 Stmt *RangeDecl, Stmt *BeginEnd, Expr *Cond,
2026 Expr *Inc, Stmt *LoopVarDecl,
2027 SourceLocation RParenLoc, BuildForRangeKind Kind) {
2028 Scope *S = getCurScope();
2030 DeclStmt *RangeDS = cast<DeclStmt>(RangeDecl);
2031 VarDecl *RangeVar = cast<VarDecl>(RangeDS->getSingleDecl());
2032 QualType RangeVarType = RangeVar->getType();
2034 DeclStmt *LoopVarDS = cast<DeclStmt>(LoopVarDecl);
2035 VarDecl *LoopVar = cast<VarDecl>(LoopVarDS->getSingleDecl());
2037 // If we hit any errors, mark the loop variable as invalid if its type
2039 InvalidateOnErrorScope Invalidate(*this, LoopVar,
2040 LoopVar->getType()->isUndeducedType());
2042 StmtResult BeginEndDecl = BeginEnd;
2043 ExprResult NotEqExpr = Cond, IncrExpr = Inc;
2045 if (RangeVarType->isDependentType()) {
2046 // The range is implicitly used as a placeholder when it is dependent.
2047 RangeVar->markUsed(Context);
2049 // Deduce any 'auto's in the loop variable as 'DependentTy'. We'll fill
2050 // them in properly when we instantiate the loop.
2051 if (!LoopVar->isInvalidDecl() && Kind != BFRK_Check)
2052 LoopVar->setType(SubstAutoType(LoopVar->getType(), Context.DependentTy));
2053 } else if (!BeginEndDecl.get()) {
2054 SourceLocation RangeLoc = RangeVar->getLocation();
2056 const QualType RangeVarNonRefType = RangeVarType.getNonReferenceType();
2058 ExprResult BeginRangeRef = BuildDeclRefExpr(RangeVar, RangeVarNonRefType,
2059 VK_LValue, ColonLoc);
2060 if (BeginRangeRef.isInvalid())
2063 ExprResult EndRangeRef = BuildDeclRefExpr(RangeVar, RangeVarNonRefType,
2064 VK_LValue, ColonLoc);
2065 if (EndRangeRef.isInvalid())
2068 QualType AutoType = Context.getAutoDeductType();
2069 Expr *Range = RangeVar->getInit();
2072 QualType RangeType = Range->getType();
2074 if (RequireCompleteType(RangeLoc, RangeType,
2075 diag::err_for_range_incomplete_type))
2078 // Build auto __begin = begin-expr, __end = end-expr.
2079 VarDecl *BeginVar = BuildForRangeVarDecl(*this, ColonLoc, AutoType,
2081 VarDecl *EndVar = BuildForRangeVarDecl(*this, ColonLoc, AutoType,
2084 // Build begin-expr and end-expr and attach to __begin and __end variables.
2085 ExprResult BeginExpr, EndExpr;
2086 if (const ArrayType *UnqAT = RangeType->getAsArrayTypeUnsafe()) {
2087 // - if _RangeT is an array type, begin-expr and end-expr are __range and
2088 // __range + __bound, respectively, where __bound is the array bound. If
2089 // _RangeT is an array of unknown size or an array of incomplete type,
2090 // the program is ill-formed;
2092 // begin-expr is __range.
2093 BeginExpr = BeginRangeRef;
2094 if (FinishForRangeVarDecl(*this, BeginVar, BeginRangeRef.get(), ColonLoc,
2095 diag::err_for_range_iter_deduction_failure)) {
2096 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
2100 // Find the array bound.
2101 ExprResult BoundExpr;
2102 if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(UnqAT))
2103 BoundExpr = Owned(IntegerLiteral::Create(Context, CAT->getSize(),
2104 Context.getPointerDiffType(),
2106 else if (const VariableArrayType *VAT =
2107 dyn_cast<VariableArrayType>(UnqAT))
2108 BoundExpr = VAT->getSizeExpr();
2110 // Can't be a DependentSizedArrayType or an IncompleteArrayType since
2111 // UnqAT is not incomplete and Range is not type-dependent.
2112 llvm_unreachable("Unexpected array type in for-range");
2115 // end-expr is __range + __bound.
2116 EndExpr = ActOnBinOp(S, ColonLoc, tok::plus, EndRangeRef.get(),
2118 if (EndExpr.isInvalid())
2120 if (FinishForRangeVarDecl(*this, EndVar, EndExpr.get(), ColonLoc,
2121 diag::err_for_range_iter_deduction_failure)) {
2122 NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
2126 OverloadCandidateSet CandidateSet(RangeLoc);
2127 Sema::BeginEndFunction BEFFailure;
2128 ForRangeStatus RangeStatus =
2129 BuildNonArrayForRange(*this, S, BeginRangeRef.get(),
2130 EndRangeRef.get(), RangeType,
2131 BeginVar, EndVar, ColonLoc, &CandidateSet,
2132 &BeginExpr, &EndExpr, &BEFFailure);
2134 if (Kind == BFRK_Build && RangeStatus == FRS_NoViableFunction &&
2135 BEFFailure == BEF_begin) {
2136 // If the range is being built from an array parameter, emit a
2137 // a diagnostic that it is being treated as a pointer.
2138 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Range)) {
2139 if (ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(DRE->getDecl())) {
2140 QualType ArrayTy = PVD->getOriginalType();
2141 QualType PointerTy = PVD->getType();
2142 if (PointerTy->isPointerType() && ArrayTy->isArrayType()) {
2143 Diag(Range->getLocStart(), diag::err_range_on_array_parameter)
2144 << RangeLoc << PVD << ArrayTy << PointerTy;
2145 Diag(PVD->getLocation(), diag::note_declared_at);
2151 // If building the range failed, try dereferencing the range expression
2152 // unless a diagnostic was issued or the end function is problematic.
2153 StmtResult SR = RebuildForRangeWithDereference(*this, S, ForLoc,
2154 LoopVarDecl, ColonLoc,
2157 if (SR.isInvalid() || SR.isUsable())
2161 // Otherwise, emit diagnostics if we haven't already.
2162 if (RangeStatus == FRS_NoViableFunction) {
2163 Expr *Range = BEFFailure ? EndRangeRef.get() : BeginRangeRef.get();
2164 Diag(Range->getLocStart(), diag::err_for_range_invalid)
2165 << RangeLoc << Range->getType() << BEFFailure;
2166 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Range);
2168 // Return an error if no fix was discovered.
2169 if (RangeStatus != FRS_Success)
2173 assert(!BeginExpr.isInvalid() && !EndExpr.isInvalid() &&
2174 "invalid range expression in for loop");
2176 // C++11 [dcl.spec.auto]p7: BeginType and EndType must be the same.
2177 QualType BeginType = BeginVar->getType(), EndType = EndVar->getType();
2178 if (!Context.hasSameType(BeginType, EndType)) {
2179 Diag(RangeLoc, diag::err_for_range_begin_end_types_differ)
2180 << BeginType << EndType;
2181 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
2182 NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
2185 Decl *BeginEndDecls[] = { BeginVar, EndVar };
2186 // Claim the type doesn't contain auto: we've already done the checking.
2187 DeclGroupPtrTy BeginEndGroup =
2188 BuildDeclaratorGroup(llvm::MutableArrayRef<Decl *>(BeginEndDecls, 2),
2189 /*TypeMayContainAuto=*/ false);
2190 BeginEndDecl = ActOnDeclStmt(BeginEndGroup, ColonLoc, ColonLoc);
2192 const QualType BeginRefNonRefType = BeginType.getNonReferenceType();
2193 ExprResult BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType,
2194 VK_LValue, ColonLoc);
2195 if (BeginRef.isInvalid())
2198 ExprResult EndRef = BuildDeclRefExpr(EndVar, EndType.getNonReferenceType(),
2199 VK_LValue, ColonLoc);
2200 if (EndRef.isInvalid())
2203 // Build and check __begin != __end expression.
2204 NotEqExpr = ActOnBinOp(S, ColonLoc, tok::exclaimequal,
2205 BeginRef.get(), EndRef.get());
2206 NotEqExpr = ActOnBooleanCondition(S, ColonLoc, NotEqExpr.get());
2207 NotEqExpr = ActOnFinishFullExpr(NotEqExpr.get());
2208 if (NotEqExpr.isInvalid()) {
2209 Diag(RangeLoc, diag::note_for_range_invalid_iterator)
2210 << RangeLoc << 0 << BeginRangeRef.get()->getType();
2211 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
2212 if (!Context.hasSameType(BeginType, EndType))
2213 NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
2217 // Build and check ++__begin expression.
2218 BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType,
2219 VK_LValue, ColonLoc);
2220 if (BeginRef.isInvalid())
2223 IncrExpr = ActOnUnaryOp(S, ColonLoc, tok::plusplus, BeginRef.get());
2224 IncrExpr = ActOnFinishFullExpr(IncrExpr.get());
2225 if (IncrExpr.isInvalid()) {
2226 Diag(RangeLoc, diag::note_for_range_invalid_iterator)
2227 << RangeLoc << 2 << BeginRangeRef.get()->getType() ;
2228 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
2232 // Build and check *__begin expression.
2233 BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType,
2234 VK_LValue, ColonLoc);
2235 if (BeginRef.isInvalid())
2238 ExprResult DerefExpr = ActOnUnaryOp(S, ColonLoc, tok::star, BeginRef.get());
2239 if (DerefExpr.isInvalid()) {
2240 Diag(RangeLoc, diag::note_for_range_invalid_iterator)
2241 << RangeLoc << 1 << BeginRangeRef.get()->getType();
2242 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
2246 // Attach *__begin as initializer for VD. Don't touch it if we're just
2247 // trying to determine whether this would be a valid range.
2248 if (!LoopVar->isInvalidDecl() && Kind != BFRK_Check) {
2249 AddInitializerToDecl(LoopVar, DerefExpr.get(), /*DirectInit=*/false,
2250 /*TypeMayContainAuto=*/true);
2251 if (LoopVar->isInvalidDecl())
2252 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
2256 // Don't bother to actually allocate the result if we're just trying to
2257 // determine whether it would be valid.
2258 if (Kind == BFRK_Check)
2259 return StmtResult();
2261 return Owned(new (Context) CXXForRangeStmt(RangeDS,
2262 cast_or_null<DeclStmt>(BeginEndDecl.get()),
2263 NotEqExpr.take(), IncrExpr.take(),
2264 LoopVarDS, /*Body=*/0, ForLoc,
2265 ColonLoc, RParenLoc));
2268 /// FinishObjCForCollectionStmt - Attach the body to a objective-C foreach
2270 StmtResult Sema::FinishObjCForCollectionStmt(Stmt *S, Stmt *B) {
2273 ObjCForCollectionStmt * ForStmt = cast<ObjCForCollectionStmt>(S);
2275 ForStmt->setBody(B);
2279 /// FinishCXXForRangeStmt - Attach the body to a C++0x for-range statement.
2280 /// This is a separate step from ActOnCXXForRangeStmt because analysis of the
2281 /// body cannot be performed until after the type of the range variable is
2283 StmtResult Sema::FinishCXXForRangeStmt(Stmt *S, Stmt *B) {
2287 if (isa<ObjCForCollectionStmt>(S))
2288 return FinishObjCForCollectionStmt(S, B);
2290 CXXForRangeStmt *ForStmt = cast<CXXForRangeStmt>(S);
2291 ForStmt->setBody(B);
2293 DiagnoseEmptyStmtBody(ForStmt->getRParenLoc(), B,
2294 diag::warn_empty_range_based_for_body);
2299 StmtResult Sema::ActOnGotoStmt(SourceLocation GotoLoc,
2300 SourceLocation LabelLoc,
2301 LabelDecl *TheDecl) {
2302 getCurFunction()->setHasBranchIntoScope();
2303 TheDecl->markUsed(Context);
2304 return Owned(new (Context) GotoStmt(TheDecl, GotoLoc, LabelLoc));
2308 Sema::ActOnIndirectGotoStmt(SourceLocation GotoLoc, SourceLocation StarLoc,
2310 // Convert operand to void*
2311 if (!E->isTypeDependent()) {
2312 QualType ETy = E->getType();
2313 QualType DestTy = Context.getPointerType(Context.VoidTy.withConst());
2314 ExprResult ExprRes = Owned(E);
2315 AssignConvertType ConvTy =
2316 CheckSingleAssignmentConstraints(DestTy, ExprRes);
2317 if (ExprRes.isInvalid())
2320 if (DiagnoseAssignmentResult(ConvTy, StarLoc, DestTy, ETy, E, AA_Passing))
2324 ExprResult ExprRes = ActOnFinishFullExpr(E);
2325 if (ExprRes.isInvalid())
2329 getCurFunction()->setHasIndirectGoto();
2331 return Owned(new (Context) IndirectGotoStmt(GotoLoc, StarLoc, E));
2335 Sema::ActOnContinueStmt(SourceLocation ContinueLoc, Scope *CurScope) {
2336 Scope *S = CurScope->getContinueParent();
2338 // C99 6.8.6.2p1: A break shall appear only in or as a loop body.
2339 return StmtError(Diag(ContinueLoc, diag::err_continue_not_in_loop));
2342 return Owned(new (Context) ContinueStmt(ContinueLoc));
2346 Sema::ActOnBreakStmt(SourceLocation BreakLoc, Scope *CurScope) {
2347 Scope *S = CurScope->getBreakParent();
2349 // C99 6.8.6.3p1: A break shall appear only in or as a switch/loop body.
2350 return StmtError(Diag(BreakLoc, diag::err_break_not_in_loop_or_switch));
2353 return Owned(new (Context) BreakStmt(BreakLoc));
2356 /// \brief Determine whether the given expression is a candidate for
2357 /// copy elision in either a return statement or a throw expression.
2359 /// \param ReturnType If we're determining the copy elision candidate for
2360 /// a return statement, this is the return type of the function. If we're
2361 /// determining the copy elision candidate for a throw expression, this will
2364 /// \param E The expression being returned from the function or block, or
2367 /// \param AllowFunctionParameter Whether we allow function parameters to
2368 /// be considered NRVO candidates. C++ prohibits this for NRVO itself, but
2369 /// we re-use this logic to determine whether we should try to move as part of
2370 /// a return or throw (which does allow function parameters).
2372 /// \returns The NRVO candidate variable, if the return statement may use the
2373 /// NRVO, or NULL if there is no such candidate.
2374 const VarDecl *Sema::getCopyElisionCandidate(QualType ReturnType,
2376 bool AllowFunctionParameter) {
2377 QualType ExprType = E->getType();
2378 // - in a return statement in a function with ...
2379 // ... a class return type ...
2380 if (!ReturnType.isNull()) {
2381 if (!ReturnType->isRecordType())
2383 // ... the same cv-unqualified type as the function return type ...
2384 if (!Context.hasSameUnqualifiedType(ReturnType, ExprType))
2388 // ... the expression is the name of a non-volatile automatic object
2389 // (other than a function or catch-clause parameter)) ...
2390 const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(E->IgnoreParens());
2391 if (!DR || DR->refersToEnclosingLocal())
2393 const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl());
2397 // ...object (other than a function or catch-clause parameter)...
2398 if (VD->getKind() != Decl::Var &&
2399 !(AllowFunctionParameter && VD->getKind() == Decl::ParmVar))
2401 if (VD->isExceptionVariable()) return 0;
2404 if (!VD->hasLocalStorage()) return 0;
2406 // ...non-volatile...
2407 if (VD->getType().isVolatileQualified()) return 0;
2408 if (VD->getType()->isReferenceType()) return 0;
2410 // __block variables can't be allocated in a way that permits NRVO.
2411 if (VD->hasAttr<BlocksAttr>()) return 0;
2413 // Variables with higher required alignment than their type's ABI
2414 // alignment cannot use NRVO.
2415 if (VD->hasAttr<AlignedAttr>() &&
2416 Context.getDeclAlign(VD) > Context.getTypeAlignInChars(VD->getType()))
2422 /// \brief Perform the initialization of a potentially-movable value, which
2423 /// is the result of return value.
2425 /// This routine implements C++0x [class.copy]p33, which attempts to treat
2426 /// returned lvalues as rvalues in certain cases (to prefer move construction),
2427 /// then falls back to treating them as lvalues if that failed.
2429 Sema::PerformMoveOrCopyInitialization(const InitializedEntity &Entity,
2430 const VarDecl *NRVOCandidate,
2431 QualType ResultType,
2434 // C++0x [class.copy]p33:
2435 // When the criteria for elision of a copy operation are met or would
2436 // be met save for the fact that the source object is a function
2437 // parameter, and the object to be copied is designated by an lvalue,
2438 // overload resolution to select the constructor for the copy is first
2439 // performed as if the object were designated by an rvalue.
2440 ExprResult Res = ExprError();
2442 (NRVOCandidate || getCopyElisionCandidate(ResultType, Value, true))) {
2443 ImplicitCastExpr AsRvalue(ImplicitCastExpr::OnStack,
2444 Value->getType(), CK_NoOp, Value, VK_XValue);
2446 Expr *InitExpr = &AsRvalue;
2447 InitializationKind Kind
2448 = InitializationKind::CreateCopy(Value->getLocStart(),
2449 Value->getLocStart());
2450 InitializationSequence Seq(*this, Entity, Kind, InitExpr);
2452 // [...] If overload resolution fails, or if the type of the first
2453 // parameter of the selected constructor is not an rvalue reference
2454 // to the object's type (possibly cv-qualified), overload resolution
2455 // is performed again, considering the object as an lvalue.
2457 for (InitializationSequence::step_iterator Step = Seq.step_begin(),
2458 StepEnd = Seq.step_end();
2459 Step != StepEnd; ++Step) {
2460 if (Step->Kind != InitializationSequence::SK_ConstructorInitialization)
2463 CXXConstructorDecl *Constructor
2464 = cast<CXXConstructorDecl>(Step->Function.Function);
2466 const RValueReferenceType *RRefType
2467 = Constructor->getParamDecl(0)->getType()
2468 ->getAs<RValueReferenceType>();
2470 // If we don't meet the criteria, break out now.
2472 !Context.hasSameUnqualifiedType(RRefType->getPointeeType(),
2473 Context.getTypeDeclType(Constructor->getParent())))
2476 // Promote "AsRvalue" to the heap, since we now need this
2477 // expression node to persist.
2478 Value = ImplicitCastExpr::Create(Context, Value->getType(),
2479 CK_NoOp, Value, 0, VK_XValue);
2481 // Complete type-checking the initialization of the return type
2482 // using the constructor we found.
2483 Res = Seq.Perform(*this, Entity, Kind, Value);
2488 // Either we didn't meet the criteria for treating an lvalue as an rvalue,
2489 // above, or overload resolution failed. Either way, we need to try
2490 // (again) now with the return value expression as written.
2491 if (Res.isInvalid())
2492 Res = PerformCopyInitialization(Entity, SourceLocation(), Value);
2497 /// \brief Determine whether the declared return type of the specified function
2498 /// contains 'auto'.
2499 static bool hasDeducedReturnType(FunctionDecl *FD) {
2500 const FunctionProtoType *FPT =
2501 FD->getTypeSourceInfo()->getType()->castAs<FunctionProtoType>();
2502 return FPT->getResultType()->isUndeducedType();
2505 /// ActOnCapScopeReturnStmt - Utility routine to type-check return statements
2506 /// for capturing scopes.
2509 Sema::ActOnCapScopeReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) {
2510 // If this is the first return we've seen, infer the return type.
2511 // [expr.prim.lambda]p4 in C++11; block literals follow the same rules.
2512 CapturingScopeInfo *CurCap = cast<CapturingScopeInfo>(getCurFunction());
2513 QualType FnRetType = CurCap->ReturnType;
2514 LambdaScopeInfo *CurLambda = dyn_cast<LambdaScopeInfo>(CurCap);
2516 if (CurLambda && hasDeducedReturnType(CurLambda->CallOperator)) {
2517 // In C++1y, the return type may involve 'auto'.
2518 // FIXME: Blocks might have a return type of 'auto' explicitly specified.
2519 FunctionDecl *FD = CurLambda->CallOperator;
2520 if (CurCap->ReturnType.isNull())
2521 CurCap->ReturnType = FD->getResultType();
2523 AutoType *AT = CurCap->ReturnType->getContainedAutoType();
2524 assert(AT && "lost auto type from lambda return type");
2525 if (DeduceFunctionTypeFromReturnExpr(FD, ReturnLoc, RetValExp, AT)) {
2526 FD->setInvalidDecl();
2529 CurCap->ReturnType = FnRetType = FD->getResultType();
2530 } else if (CurCap->HasImplicitReturnType) {
2531 // For blocks/lambdas with implicit return types, we check each return
2532 // statement individually, and deduce the common return type when the block
2533 // or lambda is completed.
2534 // FIXME: Fold this into the 'auto' codepath above.
2535 if (RetValExp && !isa<InitListExpr>(RetValExp)) {
2536 ExprResult Result = DefaultFunctionArrayLvalueConversion(RetValExp);
2537 if (Result.isInvalid())
2539 RetValExp = Result.take();
2541 if (!CurContext->isDependentContext())
2542 FnRetType = RetValExp->getType();
2544 FnRetType = CurCap->ReturnType = Context.DependentTy;
2547 // C++11 [expr.lambda.prim]p4 bans inferring the result from an
2548 // initializer list, because it is not an expression (even
2549 // though we represent it as one). We still deduce 'void'.
2550 Diag(ReturnLoc, diag::err_lambda_return_init_list)
2551 << RetValExp->getSourceRange();
2554 FnRetType = Context.VoidTy;
2557 // Although we'll properly infer the type of the block once it's completed,
2558 // make sure we provide a return type now for better error recovery.
2559 if (CurCap->ReturnType.isNull())
2560 CurCap->ReturnType = FnRetType;
2562 assert(!FnRetType.isNull());
2564 if (BlockScopeInfo *CurBlock = dyn_cast<BlockScopeInfo>(CurCap)) {
2565 if (CurBlock->FunctionType->getAs<FunctionType>()->getNoReturnAttr()) {
2566 Diag(ReturnLoc, diag::err_noreturn_block_has_return_expr);
2569 } else if (CapturedRegionScopeInfo *CurRegion =
2570 dyn_cast<CapturedRegionScopeInfo>(CurCap)) {
2571 Diag(ReturnLoc, diag::err_return_in_captured_stmt) << CurRegion->getRegionName();
2574 assert(CurLambda && "unknown kind of captured scope");
2575 if (CurLambda->CallOperator->getType()->getAs<FunctionType>()
2576 ->getNoReturnAttr()) {
2577 Diag(ReturnLoc, diag::err_noreturn_lambda_has_return_expr);
2582 // Otherwise, verify that this result type matches the previous one. We are
2583 // pickier with blocks than for normal functions because we don't have GCC
2584 // compatibility to worry about here.
2585 const VarDecl *NRVOCandidate = 0;
2586 if (FnRetType->isDependentType()) {
2587 // Delay processing for now. TODO: there are lots of dependent
2588 // types we can conclusively prove aren't void.
2589 } else if (FnRetType->isVoidType()) {
2590 if (RetValExp && !isa<InitListExpr>(RetValExp) &&
2591 !(getLangOpts().CPlusPlus &&
2592 (RetValExp->isTypeDependent() ||
2593 RetValExp->getType()->isVoidType()))) {
2594 if (!getLangOpts().CPlusPlus &&
2595 RetValExp->getType()->isVoidType())
2596 Diag(ReturnLoc, diag::ext_return_has_void_expr) << "literal" << 2;
2598 Diag(ReturnLoc, diag::err_return_block_has_expr);
2602 } else if (!RetValExp) {
2603 return StmtError(Diag(ReturnLoc, diag::err_block_return_missing_expr));
2604 } else if (!RetValExp->isTypeDependent()) {
2605 // we have a non-void block with an expression, continue checking
2607 // C99 6.8.6.4p3(136): The return statement is not an assignment. The
2608 // overlap restriction of subclause 6.5.16.1 does not apply to the case of
2611 // In C++ the return statement is handled via a copy initialization.
2612 // the C version of which boils down to CheckSingleAssignmentConstraints.
2613 NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false);
2614 InitializedEntity Entity = InitializedEntity::InitializeResult(ReturnLoc,
2616 NRVOCandidate != 0);
2617 ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRVOCandidate,
2618 FnRetType, RetValExp);
2619 if (Res.isInvalid()) {
2620 // FIXME: Cleanup temporaries here, anyway?
2623 RetValExp = Res.take();
2624 CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc);
2628 ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc);
2631 RetValExp = ER.take();
2633 ReturnStmt *Result = new (Context) ReturnStmt(ReturnLoc, RetValExp,
2636 // If we need to check for the named return value optimization,
2637 // or if we need to infer the return type,
2638 // save the return statement in our scope for later processing.
2639 if (CurCap->HasImplicitReturnType ||
2640 (getLangOpts().CPlusPlus && FnRetType->isRecordType() &&
2641 !CurContext->isDependentContext()))
2642 FunctionScopes.back()->Returns.push_back(Result);
2644 return Owned(Result);
2647 /// Deduce the return type for a function from a returned expression, per
2648 /// C++1y [dcl.spec.auto]p6.
2649 bool Sema::DeduceFunctionTypeFromReturnExpr(FunctionDecl *FD,
2650 SourceLocation ReturnLoc,
2653 TypeLoc OrigResultType = FD->getTypeSourceInfo()->getTypeLoc().
2654 IgnoreParens().castAs<FunctionProtoTypeLoc>().getResultLoc();
2657 if (RetExpr && isa<InitListExpr>(RetExpr)) {
2658 // If the deduction is for a return statement and the initializer is
2659 // a braced-init-list, the program is ill-formed.
2660 Diag(RetExpr->getExprLoc(),
2661 getCurLambda() ? diag::err_lambda_return_init_list
2662 : diag::err_auto_fn_return_init_list)
2663 << RetExpr->getSourceRange();
2667 if (FD->isDependentContext()) {
2668 // C++1y [dcl.spec.auto]p12:
2669 // Return type deduction [...] occurs when the definition is
2670 // instantiated even if the function body contains a return
2671 // statement with a non-type-dependent operand.
2672 assert(AT->isDeduced() && "should have deduced to dependent type");
2674 } else if (RetExpr) {
2675 // If the deduction is for a return statement and the initializer is
2676 // a braced-init-list, the program is ill-formed.
2677 if (isa<InitListExpr>(RetExpr)) {
2678 Diag(RetExpr->getExprLoc(), diag::err_auto_fn_return_init_list);
2682 // Otherwise, [...] deduce a value for U using the rules of template
2683 // argument deduction.
2684 DeduceAutoResult DAR = DeduceAutoType(OrigResultType, RetExpr, Deduced);
2686 if (DAR == DAR_Failed && !FD->isInvalidDecl())
2687 Diag(RetExpr->getExprLoc(), diag::err_auto_fn_deduction_failure)
2688 << OrigResultType.getType() << RetExpr->getType();
2690 if (DAR != DAR_Succeeded)
2693 // In the case of a return with no operand, the initializer is considered
2696 // Deduction here can only succeed if the return type is exactly 'cv auto'
2697 // or 'decltype(auto)', so just check for that case directly.
2698 if (!OrigResultType.getType()->getAs<AutoType>()) {
2699 Diag(ReturnLoc, diag::err_auto_fn_return_void_but_not_auto)
2700 << OrigResultType.getType();
2703 // We always deduce U = void in this case.
2704 Deduced = SubstAutoType(OrigResultType.getType(), Context.VoidTy);
2705 if (Deduced.isNull())
2709 // If a function with a declared return type that contains a placeholder type
2710 // has multiple return statements, the return type is deduced for each return
2711 // statement. [...] if the type deduced is not the same in each deduction,
2712 // the program is ill-formed.
2713 if (AT->isDeduced() && !FD->isInvalidDecl()) {
2714 AutoType *NewAT = Deduced->getContainedAutoType();
2715 if (!FD->isDependentContext() &&
2716 !Context.hasSameType(AT->getDeducedType(), NewAT->getDeducedType())) {
2717 const LambdaScopeInfo *LambdaSI = getCurLambda();
2718 if (LambdaSI && LambdaSI->HasImplicitReturnType) {
2719 Diag(ReturnLoc, diag::err_typecheck_missing_return_type_incompatible)
2720 << NewAT->getDeducedType() << AT->getDeducedType()
2721 << true /*IsLambda*/;
2723 Diag(ReturnLoc, diag::err_auto_fn_different_deductions)
2724 << (AT->isDecltypeAuto() ? 1 : 0)
2725 << NewAT->getDeducedType() << AT->getDeducedType();
2729 } else if (!FD->isInvalidDecl()) {
2730 // Update all declarations of the function to have the deduced return type.
2731 Context.adjustDeducedFunctionResultType(FD, Deduced);
2738 Sema::ActOnReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) {
2739 // Check for unexpanded parameter packs.
2740 if (RetValExp && DiagnoseUnexpandedParameterPack(RetValExp))
2743 if (isa<CapturingScopeInfo>(getCurFunction()))
2744 return ActOnCapScopeReturnStmt(ReturnLoc, RetValExp);
2747 QualType RelatedRetType;
2748 if (const FunctionDecl *FD = getCurFunctionDecl()) {
2749 FnRetType = FD->getResultType();
2750 if (FD->isNoReturn())
2751 Diag(ReturnLoc, diag::warn_noreturn_function_has_return_expr)
2752 << FD->getDeclName();
2753 } else if (ObjCMethodDecl *MD = getCurMethodDecl()) {
2754 FnRetType = MD->getResultType();
2755 if (MD->hasRelatedResultType() && MD->getClassInterface()) {
2756 // In the implementation of a method with a related return type, the
2757 // type used to type-check the validity of return statements within the
2758 // method body is a pointer to the type of the class being implemented.
2759 RelatedRetType = Context.getObjCInterfaceType(MD->getClassInterface());
2760 RelatedRetType = Context.getObjCObjectPointerType(RelatedRetType);
2762 } else // If we don't have a function/method context, bail.
2765 // FIXME: Add a flag to the ScopeInfo to indicate whether we're performing
2767 if (getLangOpts().CPlusPlus1y) {
2768 if (AutoType *AT = FnRetType->getContainedAutoType()) {
2769 FunctionDecl *FD = cast<FunctionDecl>(CurContext);
2770 if (DeduceFunctionTypeFromReturnExpr(FD, ReturnLoc, RetValExp, AT)) {
2771 FD->setInvalidDecl();
2774 FnRetType = FD->getResultType();
2779 bool HasDependentReturnType = FnRetType->isDependentType();
2781 ReturnStmt *Result = 0;
2782 if (FnRetType->isVoidType()) {
2784 if (isa<InitListExpr>(RetValExp)) {
2785 // We simply never allow init lists as the return value of void
2786 // functions. This is compatible because this was never allowed before,
2787 // so there's no legacy code to deal with.
2788 NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
2789 int FunctionKind = 0;
2790 if (isa<ObjCMethodDecl>(CurDecl))
2792 else if (isa<CXXConstructorDecl>(CurDecl))
2794 else if (isa<CXXDestructorDecl>(CurDecl))
2797 Diag(ReturnLoc, diag::err_return_init_list)
2798 << CurDecl->getDeclName() << FunctionKind
2799 << RetValExp->getSourceRange();
2801 // Drop the expression.
2803 } else if (!RetValExp->isTypeDependent()) {
2804 // C99 6.8.6.4p1 (ext_ since GCC warns)
2805 unsigned D = diag::ext_return_has_expr;
2806 if (RetValExp->getType()->isVoidType())
2807 D = diag::ext_return_has_void_expr;
2809 ExprResult Result = Owned(RetValExp);
2810 Result = IgnoredValueConversions(Result.take());
2811 if (Result.isInvalid())
2813 RetValExp = Result.take();
2814 RetValExp = ImpCastExprToType(RetValExp,
2815 Context.VoidTy, CK_ToVoid).take();
2818 // return (some void expression); is legal in C++.
2819 if (D != diag::ext_return_has_void_expr ||
2820 !getLangOpts().CPlusPlus) {
2821 NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
2823 int FunctionKind = 0;
2824 if (isa<ObjCMethodDecl>(CurDecl))
2826 else if (isa<CXXConstructorDecl>(CurDecl))
2828 else if (isa<CXXDestructorDecl>(CurDecl))
2832 << CurDecl->getDeclName() << FunctionKind
2833 << RetValExp->getSourceRange();
2838 ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc);
2841 RetValExp = ER.take();
2845 Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, 0);
2846 } else if (!RetValExp && !HasDependentReturnType) {
2847 unsigned DiagID = diag::warn_return_missing_expr; // C90 6.6.6.4p4
2848 // C99 6.8.6.4p1 (ext_ since GCC warns)
2849 if (getLangOpts().C99) DiagID = diag::ext_return_missing_expr;
2851 if (FunctionDecl *FD = getCurFunctionDecl())
2852 Diag(ReturnLoc, DiagID) << FD->getIdentifier() << 0/*fn*/;
2854 Diag(ReturnLoc, DiagID) << getCurMethodDecl()->getDeclName() << 1/*meth*/;
2855 Result = new (Context) ReturnStmt(ReturnLoc);
2857 assert(RetValExp || HasDependentReturnType);
2858 const VarDecl *NRVOCandidate = 0;
2859 if (!HasDependentReturnType && !RetValExp->isTypeDependent()) {
2860 // we have a non-void function with an expression, continue checking
2862 QualType RetType = (RelatedRetType.isNull() ? FnRetType : RelatedRetType);
2864 // C99 6.8.6.4p3(136): The return statement is not an assignment. The
2865 // overlap restriction of subclause 6.5.16.1 does not apply to the case of
2868 // In C++ the return statement is handled via a copy initialization,
2869 // the C version of which boils down to CheckSingleAssignmentConstraints.
2870 NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false);
2871 InitializedEntity Entity = InitializedEntity::InitializeResult(ReturnLoc,
2873 NRVOCandidate != 0);
2874 ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRVOCandidate,
2875 RetType, RetValExp);
2876 if (Res.isInvalid()) {
2877 // FIXME: Clean up temporaries here anyway?
2880 RetValExp = Res.takeAs<Expr>();
2882 // If we have a related result type, we need to implicitly
2883 // convert back to the formal result type. We can't pretend to
2884 // initialize the result again --- we might end double-retaining
2885 // --- so instead we initialize a notional temporary.
2886 if (!RelatedRetType.isNull()) {
2887 Entity = InitializedEntity::InitializeRelatedResult(getCurMethodDecl(),
2889 Res = PerformCopyInitialization(Entity, ReturnLoc, RetValExp);
2890 if (Res.isInvalid()) {
2891 // FIXME: Clean up temporaries here anyway?
2894 RetValExp = Res.takeAs<Expr>();
2897 CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc);
2901 ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc);
2904 RetValExp = ER.take();
2906 Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, NRVOCandidate);
2909 // If we need to check for the named return value optimization, save the
2910 // return statement in our scope for later processing.
2911 if (getLangOpts().CPlusPlus && FnRetType->isRecordType() &&
2912 !CurContext->isDependentContext())
2913 FunctionScopes.back()->Returns.push_back(Result);
2915 return Owned(Result);
2919 Sema::ActOnObjCAtCatchStmt(SourceLocation AtLoc,
2920 SourceLocation RParen, Decl *Parm,
2922 VarDecl *Var = cast_or_null<VarDecl>(Parm);
2923 if (Var && Var->isInvalidDecl())
2926 return Owned(new (Context) ObjCAtCatchStmt(AtLoc, RParen, Var, Body));
2930 Sema::ActOnObjCAtFinallyStmt(SourceLocation AtLoc, Stmt *Body) {
2931 return Owned(new (Context) ObjCAtFinallyStmt(AtLoc, Body));
2935 Sema::ActOnObjCAtTryStmt(SourceLocation AtLoc, Stmt *Try,
2936 MultiStmtArg CatchStmts, Stmt *Finally) {
2937 if (!getLangOpts().ObjCExceptions)
2938 Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@try";
2940 getCurFunction()->setHasBranchProtectedScope();
2941 unsigned NumCatchStmts = CatchStmts.size();
2942 return Owned(ObjCAtTryStmt::Create(Context, AtLoc, Try,
2948 StmtResult Sema::BuildObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw) {
2950 ExprResult Result = DefaultLvalueConversion(Throw);
2951 if (Result.isInvalid())
2954 Result = ActOnFinishFullExpr(Result.take());
2955 if (Result.isInvalid())
2957 Throw = Result.take();
2959 QualType ThrowType = Throw->getType();
2960 // Make sure the expression type is an ObjC pointer or "void *".
2961 if (!ThrowType->isDependentType() &&
2962 !ThrowType->isObjCObjectPointerType()) {
2963 const PointerType *PT = ThrowType->getAs<PointerType>();
2964 if (!PT || !PT->getPointeeType()->isVoidType())
2965 return StmtError(Diag(AtLoc, diag::error_objc_throw_expects_object)
2966 << Throw->getType() << Throw->getSourceRange());
2970 return Owned(new (Context) ObjCAtThrowStmt(AtLoc, Throw));
2974 Sema::ActOnObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw,
2976 if (!getLangOpts().ObjCExceptions)
2977 Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@throw";
2980 // @throw without an expression designates a rethrow (which much occur
2981 // in the context of an @catch clause).
2982 Scope *AtCatchParent = CurScope;
2983 while (AtCatchParent && !AtCatchParent->isAtCatchScope())
2984 AtCatchParent = AtCatchParent->getParent();
2986 return StmtError(Diag(AtLoc, diag::error_rethrow_used_outside_catch));
2988 return BuildObjCAtThrowStmt(AtLoc, Throw);
2992 Sema::ActOnObjCAtSynchronizedOperand(SourceLocation atLoc, Expr *operand) {
2993 ExprResult result = DefaultLvalueConversion(operand);
2994 if (result.isInvalid())
2996 operand = result.take();
2998 // Make sure the expression type is an ObjC pointer or "void *".
2999 QualType type = operand->getType();
3000 if (!type->isDependentType() &&
3001 !type->isObjCObjectPointerType()) {
3002 const PointerType *pointerType = type->getAs<PointerType>();
3003 if (!pointerType || !pointerType->getPointeeType()->isVoidType())
3004 return Diag(atLoc, diag::error_objc_synchronized_expects_object)
3005 << type << operand->getSourceRange();
3008 // The operand to @synchronized is a full-expression.
3009 return ActOnFinishFullExpr(operand);
3013 Sema::ActOnObjCAtSynchronizedStmt(SourceLocation AtLoc, Expr *SyncExpr,
3015 // We can't jump into or indirect-jump out of a @synchronized block.
3016 getCurFunction()->setHasBranchProtectedScope();
3017 return Owned(new (Context) ObjCAtSynchronizedStmt(AtLoc, SyncExpr, SyncBody));
3020 /// ActOnCXXCatchBlock - Takes an exception declaration and a handler block
3021 /// and creates a proper catch handler from them.
3023 Sema::ActOnCXXCatchBlock(SourceLocation CatchLoc, Decl *ExDecl,
3024 Stmt *HandlerBlock) {
3025 // There's nothing to test that ActOnExceptionDecl didn't already test.
3026 return Owned(new (Context) CXXCatchStmt(CatchLoc,
3027 cast_or_null<VarDecl>(ExDecl),
3032 Sema::ActOnObjCAutoreleasePoolStmt(SourceLocation AtLoc, Stmt *Body) {
3033 getCurFunction()->setHasBranchProtectedScope();
3034 return Owned(new (Context) ObjCAutoreleasePoolStmt(AtLoc, Body));
3039 class TypeWithHandler {
3043 TypeWithHandler(const QualType &type, CXXCatchStmt *statement)
3044 : t(type), stmt(statement) {}
3046 // An arbitrary order is fine as long as it places identical
3047 // types next to each other.
3048 bool operator<(const TypeWithHandler &y) const {
3049 if (t.getAsOpaquePtr() < y.t.getAsOpaquePtr())
3051 if (t.getAsOpaquePtr() > y.t.getAsOpaquePtr())
3054 return getTypeSpecStartLoc() < y.getTypeSpecStartLoc();
3057 bool operator==(const TypeWithHandler& other) const {
3058 return t == other.t;
3061 CXXCatchStmt *getCatchStmt() const { return stmt; }
3062 SourceLocation getTypeSpecStartLoc() const {
3063 return stmt->getExceptionDecl()->getTypeSpecStartLoc();
3069 /// ActOnCXXTryBlock - Takes a try compound-statement and a number of
3070 /// handlers and creates a try statement from them.
3071 StmtResult Sema::ActOnCXXTryBlock(SourceLocation TryLoc, Stmt *TryBlock,
3072 ArrayRef<Stmt *> Handlers) {
3073 // Don't report an error if 'try' is used in system headers.
3074 if (!getLangOpts().CXXExceptions &&
3075 !getSourceManager().isInSystemHeader(TryLoc))
3076 Diag(TryLoc, diag::err_exceptions_disabled) << "try";
3078 const unsigned NumHandlers = Handlers.size();
3079 assert(NumHandlers > 0 &&
3080 "The parser shouldn't call this if there are no handlers.");
3082 SmallVector<TypeWithHandler, 8> TypesWithHandlers;
3084 for (unsigned i = 0; i < NumHandlers; ++i) {
3085 CXXCatchStmt *Handler = cast<CXXCatchStmt>(Handlers[i]);
3086 if (!Handler->getExceptionDecl()) {
3087 if (i < NumHandlers - 1)
3088 return StmtError(Diag(Handler->getLocStart(),
3089 diag::err_early_catch_all));
3094 const QualType CaughtType = Handler->getCaughtType();
3095 const QualType CanonicalCaughtType = Context.getCanonicalType(CaughtType);
3096 TypesWithHandlers.push_back(TypeWithHandler(CanonicalCaughtType, Handler));
3099 // Detect handlers for the same type as an earlier one.
3100 if (NumHandlers > 1) {
3101 llvm::array_pod_sort(TypesWithHandlers.begin(), TypesWithHandlers.end());
3103 TypeWithHandler prev = TypesWithHandlers[0];
3104 for (unsigned i = 1; i < TypesWithHandlers.size(); ++i) {
3105 TypeWithHandler curr = TypesWithHandlers[i];
3108 Diag(curr.getTypeSpecStartLoc(),
3109 diag::warn_exception_caught_by_earlier_handler)
3110 << curr.getCatchStmt()->getCaughtType().getAsString();
3111 Diag(prev.getTypeSpecStartLoc(),
3112 diag::note_previous_exception_handler)
3113 << prev.getCatchStmt()->getCaughtType().getAsString();
3120 getCurFunction()->setHasBranchProtectedScope();
3122 // FIXME: We should detect handlers that cannot catch anything because an
3123 // earlier handler catches a superclass. Need to find a method that is not
3124 // quadratic for this.
3125 // Neither of these are explicitly forbidden, but every compiler detects them
3128 return Owned(CXXTryStmt::Create(Context, TryLoc, TryBlock, Handlers));
3132 Sema::ActOnSEHTryBlock(bool IsCXXTry,
3133 SourceLocation TryLoc,
3136 assert(TryBlock && Handler);
3138 getCurFunction()->setHasBranchProtectedScope();
3140 return Owned(SEHTryStmt::Create(Context,IsCXXTry,TryLoc,TryBlock,Handler));
3144 Sema::ActOnSEHExceptBlock(SourceLocation Loc,
3147 assert(FilterExpr && Block);
3149 if(!FilterExpr->getType()->isIntegerType()) {
3150 return StmtError(Diag(FilterExpr->getExprLoc(),
3151 diag::err_filter_expression_integral)
3152 << FilterExpr->getType());
3155 return Owned(SEHExceptStmt::Create(Context,Loc,FilterExpr,Block));
3159 Sema::ActOnSEHFinallyBlock(SourceLocation Loc,
3162 return Owned(SEHFinallyStmt::Create(Context,Loc,Block));
3165 StmtResult Sema::BuildMSDependentExistsStmt(SourceLocation KeywordLoc,
3167 NestedNameSpecifierLoc QualifierLoc,
3168 DeclarationNameInfo NameInfo,
3171 return new (Context) MSDependentExistsStmt(KeywordLoc, IsIfExists,
3172 QualifierLoc, NameInfo,
3173 cast<CompoundStmt>(Nested));
3177 StmtResult Sema::ActOnMSDependentExistsStmt(SourceLocation KeywordLoc,
3180 UnqualifiedId &Name,
3182 return BuildMSDependentExistsStmt(KeywordLoc, IsIfExists,
3183 SS.getWithLocInContext(Context),
3184 GetNameFromUnqualifiedId(Name),
3189 Sema::CreateCapturedStmtRecordDecl(CapturedDecl *&CD, SourceLocation Loc,
3190 unsigned NumParams) {
3191 DeclContext *DC = CurContext;
3192 while (!(DC->isFunctionOrMethod() || DC->isRecord() || DC->isFileContext()))
3193 DC = DC->getParent();
3196 if (getLangOpts().CPlusPlus)
3197 RD = CXXRecordDecl::Create(Context, TTK_Struct, DC, Loc, Loc, /*Id=*/0);
3199 RD = RecordDecl::Create(Context, TTK_Struct, DC, Loc, Loc, /*Id=*/0);
3203 RD->startDefinition();
3205 CD = CapturedDecl::Create(Context, CurContext, NumParams);
3208 // Build the context parameter
3209 assert(NumParams > 0 && "CapturedStmt requires context parameter");
3210 DC = CapturedDecl::castToDeclContext(CD);
3211 IdentifierInfo *VarName = &Context.Idents.get("__context");
3212 QualType ParamType = Context.getPointerType(Context.getTagDeclType(RD));
3213 ImplicitParamDecl *Param
3214 = ImplicitParamDecl::Create(Context, DC, Loc, VarName, ParamType);
3217 CD->setContextParam(Param);
3222 static void buildCapturedStmtCaptureList(
3223 SmallVectorImpl<CapturedStmt::Capture> &Captures,
3224 SmallVectorImpl<Expr *> &CaptureInits,
3225 ArrayRef<CapturingScopeInfo::Capture> Candidates) {
3227 typedef ArrayRef<CapturingScopeInfo::Capture>::const_iterator CaptureIter;
3228 for (CaptureIter Cap = Candidates.begin(); Cap != Candidates.end(); ++Cap) {
3230 if (Cap->isThisCapture()) {
3231 Captures.push_back(CapturedStmt::Capture(Cap->getLocation(),
3232 CapturedStmt::VCK_This));
3233 CaptureInits.push_back(Cap->getInitExpr());
3237 assert(Cap->isReferenceCapture() &&
3238 "non-reference capture not yet implemented");
3240 Captures.push_back(CapturedStmt::Capture(Cap->getLocation(),
3241 CapturedStmt::VCK_ByRef,
3242 Cap->getVariable()));
3243 CaptureInits.push_back(Cap->getInitExpr());
3247 void Sema::ActOnCapturedRegionStart(SourceLocation Loc, Scope *CurScope,
3248 CapturedRegionKind Kind,
3249 unsigned NumParams) {
3250 CapturedDecl *CD = 0;
3251 RecordDecl *RD = CreateCapturedStmtRecordDecl(CD, Loc, NumParams);
3253 // Enter the capturing scope for this captured region.
3254 PushCapturedRegionScope(CurScope, CD, RD, Kind);
3257 PushDeclContext(CurScope, CD);
3261 PushExpressionEvaluationContext(PotentiallyEvaluated);
3264 void Sema::ActOnCapturedRegionError() {
3265 DiscardCleanupsInEvaluationContext();
3266 PopExpressionEvaluationContext();
3268 CapturedRegionScopeInfo *RSI = getCurCapturedRegion();
3269 RecordDecl *Record = RSI->TheRecordDecl;
3270 Record->setInvalidDecl();
3272 SmallVector<Decl*, 4> Fields;
3273 for (RecordDecl::field_iterator I = Record->field_begin(),
3274 E = Record->field_end(); I != E; ++I)
3275 Fields.push_back(*I);
3276 ActOnFields(/*Scope=*/0, Record->getLocation(), Record, Fields,
3277 SourceLocation(), SourceLocation(), /*AttributeList=*/0);
3280 PopFunctionScopeInfo();
3283 StmtResult Sema::ActOnCapturedRegionEnd(Stmt *S) {
3284 CapturedRegionScopeInfo *RSI = getCurCapturedRegion();
3286 SmallVector<CapturedStmt::Capture, 4> Captures;
3287 SmallVector<Expr *, 4> CaptureInits;
3288 buildCapturedStmtCaptureList(Captures, CaptureInits, RSI->Captures);
3290 CapturedDecl *CD = RSI->TheCapturedDecl;
3291 RecordDecl *RD = RSI->TheRecordDecl;
3293 CapturedStmt *Res = CapturedStmt::Create(getASTContext(), S,
3294 RSI->CapRegionKind, Captures,
3295 CaptureInits, CD, RD);
3297 CD->setBody(Res->getCapturedStmt());
3298 RD->completeDefinition();
3300 DiscardCleanupsInEvaluationContext();
3301 PopExpressionEvaluationContext();
3304 PopFunctionScopeInfo();