1 //=- AnalysisBasedWarnings.cpp - Sema warnings based on libAnalysis -*- C++ -*-=//
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 defines analysis_warnings::[Policy,Executor].
11 // Together they are used by Sema to issue warnings based on inexpensive
12 // static analysis algorithms in libAnalysis.
14 //===----------------------------------------------------------------------===//
16 #include "clang/Sema/AnalysisBasedWarnings.h"
17 #include "clang/AST/DeclCXX.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/ParentMap.h"
23 #include "clang/AST/RecursiveASTVisitor.h"
24 #include "clang/AST/StmtCXX.h"
25 #include "clang/AST/StmtObjC.h"
26 #include "clang/AST/StmtVisitor.h"
27 #include "clang/Analysis/Analyses/CFGReachabilityAnalysis.h"
28 #include "clang/Analysis/Analyses/Consumed.h"
29 #include "clang/Analysis/Analyses/ReachableCode.h"
30 #include "clang/Analysis/Analyses/ThreadSafety.h"
31 #include "clang/Analysis/Analyses/UninitializedValues.h"
32 #include "clang/Analysis/AnalysisContext.h"
33 #include "clang/Analysis/CFG.h"
34 #include "clang/Analysis/CFGStmtMap.h"
35 #include "clang/Basic/SourceLocation.h"
36 #include "clang/Basic/SourceManager.h"
37 #include "clang/Lex/Lexer.h"
38 #include "clang/Lex/Preprocessor.h"
39 #include "clang/Sema/ScopeInfo.h"
40 #include "clang/Sema/SemaInternal.h"
41 #include "llvm/ADT/ArrayRef.h"
42 #include "llvm/ADT/BitVector.h"
43 #include "llvm/ADT/FoldingSet.h"
44 #include "llvm/ADT/ImmutableMap.h"
45 #include "llvm/ADT/MapVector.h"
46 #include "llvm/ADT/PostOrderIterator.h"
47 #include "llvm/ADT/SmallString.h"
48 #include "llvm/ADT/SmallVector.h"
49 #include "llvm/ADT/StringRef.h"
50 #include "llvm/Support/Casting.h"
56 using namespace clang;
58 //===----------------------------------------------------------------------===//
59 // Unreachable code analysis.
60 //===----------------------------------------------------------------------===//
63 class UnreachableCodeHandler : public reachable_code::Callback {
66 UnreachableCodeHandler(Sema &s) : S(s) {}
68 void HandleUnreachable(reachable_code::UnreachableKind UK,
70 SourceRange SilenceableCondVal,
72 SourceRange R2) override {
73 unsigned diag = diag::warn_unreachable;
75 case reachable_code::UK_Break:
76 diag = diag::warn_unreachable_break;
78 case reachable_code::UK_Return:
79 diag = diag::warn_unreachable_return;
81 case reachable_code::UK_Loop_Increment:
82 diag = diag::warn_unreachable_loop_increment;
84 case reachable_code::UK_Other:
88 S.Diag(L, diag) << R1 << R2;
90 SourceLocation Open = SilenceableCondVal.getBegin();
92 SourceLocation Close = SilenceableCondVal.getEnd();
93 Close = S.getLocForEndOfToken(Close);
94 if (Close.isValid()) {
95 S.Diag(Open, diag::note_unreachable_silence)
96 << FixItHint::CreateInsertion(Open, "/* DISABLES CODE */ (")
97 << FixItHint::CreateInsertion(Close, ")");
104 /// CheckUnreachable - Check for unreachable code.
105 static void CheckUnreachable(Sema &S, AnalysisDeclContext &AC) {
106 // As a heuristic prune all diagnostics not in the main file. Currently
107 // the majority of warnings in headers are false positives. These
108 // are largely caused by configuration state, e.g. preprocessor
109 // defined code, etc.
111 // Note that this is also a performance optimization. Analyzing
112 // headers many times can be expensive.
113 if (!S.getSourceManager().isInMainFile(AC.getDecl()->getLocStart()))
116 UnreachableCodeHandler UC(S);
117 reachable_code::FindUnreachableCode(AC, S.getPreprocessor(), UC);
120 /// \brief Warn on logical operator errors in CFGBuilder
121 class LogicalErrorHandler : public CFGCallback {
125 LogicalErrorHandler(Sema &S) : CFGCallback(), S(S) {}
127 static bool HasMacroID(const Expr *E) {
128 if (E->getExprLoc().isMacroID())
131 // Recurse to children.
132 for (ConstStmtRange SubStmts = E->children(); SubStmts; ++SubStmts)
134 if (const Expr *SubExpr = dyn_cast<Expr>(*SubStmts))
135 if (HasMacroID(SubExpr))
141 void compareAlwaysTrue(const BinaryOperator *B, bool isAlwaysTrue) {
145 SourceRange DiagRange = B->getSourceRange();
146 S.Diag(B->getExprLoc(), diag::warn_tautological_overlap_comparison)
147 << DiagRange << isAlwaysTrue;
150 void compareBitwiseEquality(const BinaryOperator *B, bool isAlwaysTrue) {
154 SourceRange DiagRange = B->getSourceRange();
155 S.Diag(B->getExprLoc(), diag::warn_comparison_bitwise_always)
156 << DiagRange << isAlwaysTrue;
161 //===----------------------------------------------------------------------===//
162 // Check for infinite self-recursion in functions
163 //===----------------------------------------------------------------------===//
165 // All blocks are in one of three states. States are ordered so that blocks
166 // can only move to higher states.
167 enum RecursiveState {
170 FoundPathWithNoRecursiveCall
173 static void checkForFunctionCall(Sema &S, const FunctionDecl *FD,
174 CFGBlock &Block, unsigned ExitID,
175 llvm::SmallVectorImpl<RecursiveState> &States,
176 RecursiveState State) {
177 unsigned ID = Block.getBlockID();
179 // A block's state can only move to a higher state.
180 if (States[ID] >= State)
185 // Found a path to the exit node without a recursive call.
186 if (ID == ExitID && State == FoundPathWithNoRecursiveCall)
189 if (State == FoundPathWithNoRecursiveCall) {
190 // If the current state is FoundPathWithNoRecursiveCall, the successors
191 // will be either FoundPathWithNoRecursiveCall or FoundPath. To determine
192 // which, process all the Stmt's in this block to find any recursive calls.
193 for (const auto &B : Block) {
194 if (B.getKind() != CFGElement::Statement)
197 const CallExpr *CE = dyn_cast<CallExpr>(B.getAs<CFGStmt>()->getStmt());
198 if (CE && CE->getCalleeDecl() &&
199 CE->getCalleeDecl()->getCanonicalDecl() == FD) {
201 // Skip function calls which are qualified with a templated class.
202 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(
203 CE->getCallee()->IgnoreParenImpCasts())) {
204 if (NestedNameSpecifier *NNS = DRE->getQualifier()) {
205 if (NNS->getKind() == NestedNameSpecifier::TypeSpec &&
206 isa<TemplateSpecializationType>(NNS->getAsType())) {
212 if (const CXXMemberCallExpr *MCE = dyn_cast<CXXMemberCallExpr>(CE)) {
213 if (isa<CXXThisExpr>(MCE->getImplicitObjectArgument()) ||
214 !MCE->getMethodDecl()->isVirtual()) {
226 for (CFGBlock::succ_iterator I = Block.succ_begin(), E = Block.succ_end();
229 checkForFunctionCall(S, FD, **I, ExitID, States, State);
232 static void checkRecursiveFunction(Sema &S, const FunctionDecl *FD,
234 AnalysisDeclContext &AC) {
235 FD = FD->getCanonicalDecl();
237 // Only run on non-templated functions and non-templated members of
238 // templated classes.
239 if (FD->getTemplatedKind() != FunctionDecl::TK_NonTemplate &&
240 FD->getTemplatedKind() != FunctionDecl::TK_MemberSpecialization)
243 CFG *cfg = AC.getCFG();
246 // If the exit block is unreachable, skip processing the function.
247 if (cfg->getExit().pred_empty())
250 // Mark all nodes as FoundNoPath, then begin processing the entry block.
251 llvm::SmallVector<RecursiveState, 16> states(cfg->getNumBlockIDs(),
253 checkForFunctionCall(S, FD, cfg->getEntry(), cfg->getExit().getBlockID(),
254 states, FoundPathWithNoRecursiveCall);
256 // Check that the exit block is reachable. This prevents triggering the
257 // warning on functions that do not terminate.
258 if (states[cfg->getExit().getBlockID()] == FoundPath)
259 S.Diag(Body->getLocStart(), diag::warn_infinite_recursive_function);
262 //===----------------------------------------------------------------------===//
263 // Check for missing return value.
264 //===----------------------------------------------------------------------===//
266 enum ControlFlowKind {
271 NeverFallThroughOrReturn
274 /// CheckFallThrough - Check that we don't fall off the end of a
275 /// Statement that should return a value.
277 /// \returns AlwaysFallThrough iff we always fall off the end of the statement,
278 /// MaybeFallThrough iff we might or might not fall off the end,
279 /// NeverFallThroughOrReturn iff we never fall off the end of the statement or
280 /// return. We assume NeverFallThrough iff we never fall off the end of the
281 /// statement but we may return. We assume that functions not marked noreturn
283 static ControlFlowKind CheckFallThrough(AnalysisDeclContext &AC) {
284 CFG *cfg = AC.getCFG();
285 if (!cfg) return UnknownFallThrough;
287 // The CFG leaves in dead things, and we don't want the dead code paths to
288 // confuse us, so we mark all live things first.
289 llvm::BitVector live(cfg->getNumBlockIDs());
290 unsigned count = reachable_code::ScanReachableFromBlock(&cfg->getEntry(),
293 bool AddEHEdges = AC.getAddEHEdges();
294 if (!AddEHEdges && count != cfg->getNumBlockIDs())
295 // When there are things remaining dead, and we didn't add EH edges
296 // from CallExprs to the catch clauses, we have to go back and
297 // mark them as live.
298 for (const auto *B : *cfg) {
299 if (!live[B->getBlockID()]) {
300 if (B->pred_begin() == B->pred_end()) {
301 if (B->getTerminator() && isa<CXXTryStmt>(B->getTerminator()))
302 // When not adding EH edges from calls, catch clauses
303 // can otherwise seem dead. Avoid noting them as dead.
304 count += reachable_code::ScanReachableFromBlock(B, live);
310 // Now we know what is live, we check the live precessors of the exit block
311 // and look for fall through paths, being careful to ignore normal returns,
312 // and exceptional paths.
313 bool HasLiveReturn = false;
314 bool HasFakeEdge = false;
315 bool HasPlainEdge = false;
316 bool HasAbnormalEdge = false;
318 // Ignore default cases that aren't likely to be reachable because all
319 // enums in a switch(X) have explicit case statements.
320 CFGBlock::FilterOptions FO;
321 FO.IgnoreDefaultsWithCoveredEnums = 1;
323 for (CFGBlock::filtered_pred_iterator
324 I = cfg->getExit().filtered_pred_start_end(FO); I.hasMore(); ++I) {
325 const CFGBlock& B = **I;
326 if (!live[B.getBlockID()])
329 // Skip blocks which contain an element marked as no-return. They don't
330 // represent actually viable edges into the exit block, so mark them as
332 if (B.hasNoReturnElement()) {
333 HasAbnormalEdge = true;
337 // Destructors can appear after the 'return' in the CFG. This is
338 // normal. We need to look pass the destructors for the return
339 // statement (if it exists).
340 CFGBlock::const_reverse_iterator ri = B.rbegin(), re = B.rend();
342 for ( ; ri != re ; ++ri)
343 if (ri->getAs<CFGStmt>())
346 // No more CFGElements in the block?
348 if (B.getTerminator() && isa<CXXTryStmt>(B.getTerminator())) {
349 HasAbnormalEdge = true;
352 // A labeled empty statement, or the entry block...
357 CFGStmt CS = ri->castAs<CFGStmt>();
358 const Stmt *S = CS.getStmt();
359 if (isa<ReturnStmt>(S)) {
360 HasLiveReturn = true;
363 if (isa<ObjCAtThrowStmt>(S)) {
367 if (isa<CXXThrowExpr>(S)) {
371 if (isa<MSAsmStmt>(S)) {
372 // TODO: Verify this is correct.
374 HasLiveReturn = true;
377 if (isa<CXXTryStmt>(S)) {
378 HasAbnormalEdge = true;
381 if (std::find(B.succ_begin(), B.succ_end(), &cfg->getExit())
383 HasAbnormalEdge = true;
391 return NeverFallThrough;
392 return NeverFallThroughOrReturn;
394 if (HasAbnormalEdge || HasFakeEdge || HasLiveReturn)
395 return MaybeFallThrough;
396 // This says AlwaysFallThrough for calls to functions that are not marked
397 // noreturn, that don't return. If people would like this warning to be more
398 // accurate, such functions should be marked as noreturn.
399 return AlwaysFallThrough;
404 struct CheckFallThroughDiagnostics {
405 unsigned diag_MaybeFallThrough_HasNoReturn;
406 unsigned diag_MaybeFallThrough_ReturnsNonVoid;
407 unsigned diag_AlwaysFallThrough_HasNoReturn;
408 unsigned diag_AlwaysFallThrough_ReturnsNonVoid;
409 unsigned diag_NeverFallThroughOrReturn;
410 enum { Function, Block, Lambda } funMode;
411 SourceLocation FuncLoc;
413 static CheckFallThroughDiagnostics MakeForFunction(const Decl *Func) {
414 CheckFallThroughDiagnostics D;
415 D.FuncLoc = Func->getLocation();
416 D.diag_MaybeFallThrough_HasNoReturn =
417 diag::warn_falloff_noreturn_function;
418 D.diag_MaybeFallThrough_ReturnsNonVoid =
419 diag::warn_maybe_falloff_nonvoid_function;
420 D.diag_AlwaysFallThrough_HasNoReturn =
421 diag::warn_falloff_noreturn_function;
422 D.diag_AlwaysFallThrough_ReturnsNonVoid =
423 diag::warn_falloff_nonvoid_function;
425 // Don't suggest that virtual functions be marked "noreturn", since they
426 // might be overridden by non-noreturn functions.
427 bool isVirtualMethod = false;
428 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Func))
429 isVirtualMethod = Method->isVirtual();
431 // Don't suggest that template instantiations be marked "noreturn"
432 bool isTemplateInstantiation = false;
433 if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(Func))
434 isTemplateInstantiation = Function->isTemplateInstantiation();
436 if (!isVirtualMethod && !isTemplateInstantiation)
437 D.diag_NeverFallThroughOrReturn =
438 diag::warn_suggest_noreturn_function;
440 D.diag_NeverFallThroughOrReturn = 0;
442 D.funMode = Function;
446 static CheckFallThroughDiagnostics MakeForBlock() {
447 CheckFallThroughDiagnostics D;
448 D.diag_MaybeFallThrough_HasNoReturn =
449 diag::err_noreturn_block_has_return_expr;
450 D.diag_MaybeFallThrough_ReturnsNonVoid =
451 diag::err_maybe_falloff_nonvoid_block;
452 D.diag_AlwaysFallThrough_HasNoReturn =
453 diag::err_noreturn_block_has_return_expr;
454 D.diag_AlwaysFallThrough_ReturnsNonVoid =
455 diag::err_falloff_nonvoid_block;
456 D.diag_NeverFallThroughOrReturn = 0;
461 static CheckFallThroughDiagnostics MakeForLambda() {
462 CheckFallThroughDiagnostics D;
463 D.diag_MaybeFallThrough_HasNoReturn =
464 diag::err_noreturn_lambda_has_return_expr;
465 D.diag_MaybeFallThrough_ReturnsNonVoid =
466 diag::warn_maybe_falloff_nonvoid_lambda;
467 D.diag_AlwaysFallThrough_HasNoReturn =
468 diag::err_noreturn_lambda_has_return_expr;
469 D.diag_AlwaysFallThrough_ReturnsNonVoid =
470 diag::warn_falloff_nonvoid_lambda;
471 D.diag_NeverFallThroughOrReturn = 0;
476 bool checkDiagnostics(DiagnosticsEngine &D, bool ReturnsVoid,
477 bool HasNoReturn) const {
478 if (funMode == Function) {
479 return (ReturnsVoid ||
480 D.isIgnored(diag::warn_maybe_falloff_nonvoid_function,
483 D.isIgnored(diag::warn_noreturn_function_has_return_expr,
486 D.isIgnored(diag::warn_suggest_noreturn_block, FuncLoc));
489 // For blocks / lambdas.
490 return ReturnsVoid && !HasNoReturn;
496 /// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a
497 /// function that should return a value. Check that we don't fall off the end
498 /// of a noreturn function. We assume that functions and blocks not marked
499 /// noreturn will return.
500 static void CheckFallThroughForBody(Sema &S, const Decl *D, const Stmt *Body,
501 const BlockExpr *blkExpr,
502 const CheckFallThroughDiagnostics& CD,
503 AnalysisDeclContext &AC) {
505 bool ReturnsVoid = false;
506 bool HasNoReturn = false;
508 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
509 ReturnsVoid = FD->getReturnType()->isVoidType();
510 HasNoReturn = FD->isNoReturn();
512 else if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
513 ReturnsVoid = MD->getReturnType()->isVoidType();
514 HasNoReturn = MD->hasAttr<NoReturnAttr>();
516 else if (isa<BlockDecl>(D)) {
517 QualType BlockTy = blkExpr->getType();
518 if (const FunctionType *FT =
519 BlockTy->getPointeeType()->getAs<FunctionType>()) {
520 if (FT->getReturnType()->isVoidType())
522 if (FT->getNoReturnAttr())
527 DiagnosticsEngine &Diags = S.getDiagnostics();
529 // Short circuit for compilation speed.
530 if (CD.checkDiagnostics(Diags, ReturnsVoid, HasNoReturn))
533 SourceLocation LBrace = Body->getLocStart(), RBrace = Body->getLocEnd();
534 // Either in a function body compound statement, or a function-try-block.
535 switch (CheckFallThrough(AC)) {
536 case UnknownFallThrough:
539 case MaybeFallThrough:
541 S.Diag(RBrace, CD.diag_MaybeFallThrough_HasNoReturn);
542 else if (!ReturnsVoid)
543 S.Diag(RBrace, CD.diag_MaybeFallThrough_ReturnsNonVoid);
545 case AlwaysFallThrough:
547 S.Diag(RBrace, CD.diag_AlwaysFallThrough_HasNoReturn);
548 else if (!ReturnsVoid)
549 S.Diag(RBrace, CD.diag_AlwaysFallThrough_ReturnsNonVoid);
551 case NeverFallThroughOrReturn:
552 if (ReturnsVoid && !HasNoReturn && CD.diag_NeverFallThroughOrReturn) {
553 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
554 S.Diag(LBrace, CD.diag_NeverFallThroughOrReturn) << 0 << FD;
555 } else if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
556 S.Diag(LBrace, CD.diag_NeverFallThroughOrReturn) << 1 << MD;
558 S.Diag(LBrace, CD.diag_NeverFallThroughOrReturn);
562 case NeverFallThrough:
567 //===----------------------------------------------------------------------===//
569 //===----------------------------------------------------------------------===//
572 /// ContainsReference - A visitor class to search for references to
573 /// a particular declaration (the needle) within any evaluated component of an
574 /// expression (recursively).
575 class ContainsReference : public EvaluatedExprVisitor<ContainsReference> {
577 const DeclRefExpr *Needle;
580 ContainsReference(ASTContext &Context, const DeclRefExpr *Needle)
581 : EvaluatedExprVisitor<ContainsReference>(Context),
582 FoundReference(false), Needle(Needle) {}
584 void VisitExpr(Expr *E) {
585 // Stop evaluating if we already have a reference.
589 EvaluatedExprVisitor<ContainsReference>::VisitExpr(E);
592 void VisitDeclRefExpr(DeclRefExpr *E) {
594 FoundReference = true;
596 EvaluatedExprVisitor<ContainsReference>::VisitDeclRefExpr(E);
599 bool doesContainReference() const { return FoundReference; }
603 static bool SuggestInitializationFixit(Sema &S, const VarDecl *VD) {
604 QualType VariableTy = VD->getType().getCanonicalType();
605 if (VariableTy->isBlockPointerType() &&
606 !VD->hasAttr<BlocksAttr>()) {
607 S.Diag(VD->getLocation(), diag::note_block_var_fixit_add_initialization)
609 << FixItHint::CreateInsertion(VD->getLocation(), "__block ");
613 // Don't issue a fixit if there is already an initializer.
617 // Don't suggest a fixit inside macros.
618 if (VD->getLocEnd().isMacroID())
621 SourceLocation Loc = S.getLocForEndOfToken(VD->getLocEnd());
623 // Suggest possible initialization (if any).
624 std::string Init = S.getFixItZeroInitializerForType(VariableTy, Loc);
628 S.Diag(Loc, diag::note_var_fixit_add_initialization) << VD->getDeclName()
629 << FixItHint::CreateInsertion(Loc, Init);
633 /// Create a fixit to remove an if-like statement, on the assumption that its
634 /// condition is CondVal.
635 static void CreateIfFixit(Sema &S, const Stmt *If, const Stmt *Then,
636 const Stmt *Else, bool CondVal,
637 FixItHint &Fixit1, FixItHint &Fixit2) {
639 // If condition is always true, remove all but the 'then'.
640 Fixit1 = FixItHint::CreateRemoval(
641 CharSourceRange::getCharRange(If->getLocStart(),
642 Then->getLocStart()));
644 SourceLocation ElseKwLoc = Lexer::getLocForEndOfToken(
645 Then->getLocEnd(), 0, S.getSourceManager(), S.getLangOpts());
646 Fixit2 = FixItHint::CreateRemoval(
647 SourceRange(ElseKwLoc, Else->getLocEnd()));
650 // If condition is always false, remove all but the 'else'.
652 Fixit1 = FixItHint::CreateRemoval(
653 CharSourceRange::getCharRange(If->getLocStart(),
654 Else->getLocStart()));
656 Fixit1 = FixItHint::CreateRemoval(If->getSourceRange());
660 /// DiagUninitUse -- Helper function to produce a diagnostic for an
661 /// uninitialized use of a variable.
662 static void DiagUninitUse(Sema &S, const VarDecl *VD, const UninitUse &Use,
663 bool IsCapturedByBlock) {
664 bool Diagnosed = false;
666 switch (Use.getKind()) {
667 case UninitUse::Always:
668 S.Diag(Use.getUser()->getLocStart(), diag::warn_uninit_var)
669 << VD->getDeclName() << IsCapturedByBlock
670 << Use.getUser()->getSourceRange();
673 case UninitUse::AfterDecl:
674 case UninitUse::AfterCall:
675 S.Diag(VD->getLocation(), diag::warn_sometimes_uninit_var)
676 << VD->getDeclName() << IsCapturedByBlock
677 << (Use.getKind() == UninitUse::AfterDecl ? 4 : 5)
678 << const_cast<DeclContext*>(VD->getLexicalDeclContext())
679 << VD->getSourceRange();
680 S.Diag(Use.getUser()->getLocStart(), diag::note_uninit_var_use)
681 << IsCapturedByBlock << Use.getUser()->getSourceRange();
684 case UninitUse::Maybe:
685 case UninitUse::Sometimes:
686 // Carry on to report sometimes-uninitialized branches, if possible,
687 // or a 'may be used uninitialized' diagnostic otherwise.
691 // Diagnose each branch which leads to a sometimes-uninitialized use.
692 for (UninitUse::branch_iterator I = Use.branch_begin(), E = Use.branch_end();
694 assert(Use.getKind() == UninitUse::Sometimes);
696 const Expr *User = Use.getUser();
697 const Stmt *Term = I->Terminator;
699 // Information used when building the diagnostic.
704 // FixIts to suppress the diagnostic by removing the dead condition.
705 // For all binary terminators, branch 0 is taken if the condition is true,
706 // and branch 1 is taken if the condition is false.
707 int RemoveDiagKind = -1;
708 const char *FixitStr =
709 S.getLangOpts().CPlusPlus ? (I->Output ? "true" : "false")
710 : (I->Output ? "1" : "0");
711 FixItHint Fixit1, Fixit2;
713 switch (Term ? Term->getStmtClass() : Stmt::DeclStmtClass) {
715 // Don't know how to report this. Just fall back to 'may be used
716 // uninitialized'. FIXME: Can this happen?
719 // "condition is true / condition is false".
720 case Stmt::IfStmtClass: {
721 const IfStmt *IS = cast<IfStmt>(Term);
724 Range = IS->getCond()->getSourceRange();
726 CreateIfFixit(S, IS, IS->getThen(), IS->getElse(),
727 I->Output, Fixit1, Fixit2);
730 case Stmt::ConditionalOperatorClass: {
731 const ConditionalOperator *CO = cast<ConditionalOperator>(Term);
734 Range = CO->getCond()->getSourceRange();
736 CreateIfFixit(S, CO, CO->getTrueExpr(), CO->getFalseExpr(),
737 I->Output, Fixit1, Fixit2);
740 case Stmt::BinaryOperatorClass: {
741 const BinaryOperator *BO = cast<BinaryOperator>(Term);
742 if (!BO->isLogicalOp())
745 Str = BO->getOpcodeStr();
746 Range = BO->getLHS()->getSourceRange();
748 if ((BO->getOpcode() == BO_LAnd && I->Output) ||
749 (BO->getOpcode() == BO_LOr && !I->Output))
750 // true && y -> y, false || y -> y.
751 Fixit1 = FixItHint::CreateRemoval(SourceRange(BO->getLocStart(),
752 BO->getOperatorLoc()));
754 // false && y -> false, true || y -> true.
755 Fixit1 = FixItHint::CreateReplacement(BO->getSourceRange(), FixitStr);
759 // "loop is entered / loop is exited".
760 case Stmt::WhileStmtClass:
763 Range = cast<WhileStmt>(Term)->getCond()->getSourceRange();
765 Fixit1 = FixItHint::CreateReplacement(Range, FixitStr);
767 case Stmt::ForStmtClass:
770 Range = cast<ForStmt>(Term)->getCond()->getSourceRange();
773 Fixit1 = FixItHint::CreateRemoval(Range);
775 Fixit1 = FixItHint::CreateReplacement(Range, FixitStr);
777 case Stmt::CXXForRangeStmtClass:
778 if (I->Output == 1) {
779 // The use occurs if a range-based for loop's body never executes.
780 // That may be impossible, and there's no syntactic fix for this,
781 // so treat it as a 'may be uninitialized' case.
786 Range = cast<CXXForRangeStmt>(Term)->getRangeInit()->getSourceRange();
789 // "condition is true / loop is exited".
790 case Stmt::DoStmtClass:
793 Range = cast<DoStmt>(Term)->getCond()->getSourceRange();
795 Fixit1 = FixItHint::CreateReplacement(Range, FixitStr);
798 // "switch case is taken".
799 case Stmt::CaseStmtClass:
802 Range = cast<CaseStmt>(Term)->getLHS()->getSourceRange();
804 case Stmt::DefaultStmtClass:
807 Range = cast<DefaultStmt>(Term)->getDefaultLoc();
811 S.Diag(Range.getBegin(), diag::warn_sometimes_uninit_var)
812 << VD->getDeclName() << IsCapturedByBlock << DiagKind
813 << Str << I->Output << Range;
814 S.Diag(User->getLocStart(), diag::note_uninit_var_use)
815 << IsCapturedByBlock << User->getSourceRange();
816 if (RemoveDiagKind != -1)
817 S.Diag(Fixit1.RemoveRange.getBegin(), diag::note_uninit_fixit_remove_cond)
818 << RemoveDiagKind << Str << I->Output << Fixit1 << Fixit2;
824 S.Diag(Use.getUser()->getLocStart(), diag::warn_maybe_uninit_var)
825 << VD->getDeclName() << IsCapturedByBlock
826 << Use.getUser()->getSourceRange();
829 /// DiagnoseUninitializedUse -- Helper function for diagnosing uses of an
830 /// uninitialized variable. This manages the different forms of diagnostic
831 /// emitted for particular types of uses. Returns true if the use was diagnosed
832 /// as a warning. If a particular use is one we omit warnings for, returns
834 static bool DiagnoseUninitializedUse(Sema &S, const VarDecl *VD,
835 const UninitUse &Use,
836 bool alwaysReportSelfInit = false) {
838 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Use.getUser())) {
839 // Inspect the initializer of the variable declaration which is
840 // being referenced prior to its initialization. We emit
841 // specialized diagnostics for self-initialization, and we
842 // specifically avoid warning about self references which take the
847 // This is used to indicate to GCC that 'x' is intentionally left
848 // uninitialized. Proven code paths which access 'x' in
849 // an uninitialized state after this will still warn.
850 if (const Expr *Initializer = VD->getInit()) {
851 if (!alwaysReportSelfInit && DRE == Initializer->IgnoreParenImpCasts())
854 ContainsReference CR(S.Context, DRE);
855 CR.Visit(const_cast<Expr*>(Initializer));
856 if (CR.doesContainReference()) {
857 S.Diag(DRE->getLocStart(),
858 diag::warn_uninit_self_reference_in_init)
859 << VD->getDeclName() << VD->getLocation() << DRE->getSourceRange();
864 DiagUninitUse(S, VD, Use, false);
866 const BlockExpr *BE = cast<BlockExpr>(Use.getUser());
867 if (VD->getType()->isBlockPointerType() && !VD->hasAttr<BlocksAttr>())
868 S.Diag(BE->getLocStart(),
869 diag::warn_uninit_byref_blockvar_captured_by_block)
870 << VD->getDeclName();
872 DiagUninitUse(S, VD, Use, true);
875 // Report where the variable was declared when the use wasn't within
876 // the initializer of that declaration & we didn't already suggest
877 // an initialization fixit.
878 if (!SuggestInitializationFixit(S, VD))
879 S.Diag(VD->getLocStart(), diag::note_uninit_var_def)
880 << VD->getDeclName();
886 class FallthroughMapper : public RecursiveASTVisitor<FallthroughMapper> {
888 FallthroughMapper(Sema &S)
889 : FoundSwitchStatements(false),
893 bool foundSwitchStatements() const { return FoundSwitchStatements; }
895 void markFallthroughVisited(const AttributedStmt *Stmt) {
896 bool Found = FallthroughStmts.erase(Stmt);
901 typedef llvm::SmallPtrSet<const AttributedStmt*, 8> AttrStmts;
903 const AttrStmts &getFallthroughStmts() const {
904 return FallthroughStmts;
907 void fillReachableBlocks(CFG *Cfg) {
908 assert(ReachableBlocks.empty() && "ReachableBlocks already filled");
909 std::deque<const CFGBlock *> BlockQueue;
911 ReachableBlocks.insert(&Cfg->getEntry());
912 BlockQueue.push_back(&Cfg->getEntry());
913 // Mark all case blocks reachable to avoid problems with switching on
914 // constants, covered enums, etc.
915 // These blocks can contain fall-through annotations, and we don't want to
916 // issue a warn_fallthrough_attr_unreachable for them.
917 for (const auto *B : *Cfg) {
918 const Stmt *L = B->getLabel();
919 if (L && isa<SwitchCase>(L) && ReachableBlocks.insert(B).second)
920 BlockQueue.push_back(B);
923 while (!BlockQueue.empty()) {
924 const CFGBlock *P = BlockQueue.front();
925 BlockQueue.pop_front();
926 for (CFGBlock::const_succ_iterator I = P->succ_begin(),
929 if (*I && ReachableBlocks.insert(*I).second)
930 BlockQueue.push_back(*I);
935 bool checkFallThroughIntoBlock(const CFGBlock &B, int &AnnotatedCnt) {
936 assert(!ReachableBlocks.empty() && "ReachableBlocks empty");
938 int UnannotatedCnt = 0;
941 std::deque<const CFGBlock*> BlockQueue(B.pred_begin(), B.pred_end());
942 while (!BlockQueue.empty()) {
943 const CFGBlock *P = BlockQueue.front();
944 BlockQueue.pop_front();
947 const Stmt *Term = P->getTerminator();
948 if (Term && isa<SwitchStmt>(Term))
949 continue; // Switch statement, good.
951 const SwitchCase *SW = dyn_cast_or_null<SwitchCase>(P->getLabel());
952 if (SW && SW->getSubStmt() == B.getLabel() && P->begin() == P->end())
953 continue; // Previous case label has no statements, good.
955 const LabelStmt *L = dyn_cast_or_null<LabelStmt>(P->getLabel());
956 if (L && L->getSubStmt() == B.getLabel() && P->begin() == P->end())
957 continue; // Case label is preceded with a normal label, good.
959 if (!ReachableBlocks.count(P)) {
960 for (CFGBlock::const_reverse_iterator ElemIt = P->rbegin(),
962 ElemIt != ElemEnd; ++ElemIt) {
963 if (Optional<CFGStmt> CS = ElemIt->getAs<CFGStmt>()) {
964 if (const AttributedStmt *AS = asFallThroughAttr(CS->getStmt())) {
965 S.Diag(AS->getLocStart(),
966 diag::warn_fallthrough_attr_unreachable);
967 markFallthroughVisited(AS);
971 // Don't care about other unreachable statements.
974 // If there are no unreachable statements, this may be a special
977 // A a; // A has a destructor.
980 // // <<<< This place is represented by a 'hanging' CFG block.
985 const Stmt *LastStmt = getLastStmt(*P);
986 if (const AttributedStmt *AS = asFallThroughAttr(LastStmt)) {
987 markFallthroughVisited(AS);
989 continue; // Fallthrough annotation, good.
992 if (!LastStmt) { // This block contains no executable statements.
993 // Traverse its predecessors.
994 std::copy(P->pred_begin(), P->pred_end(),
995 std::back_inserter(BlockQueue));
1001 return !!UnannotatedCnt;
1004 // RecursiveASTVisitor setup.
1005 bool shouldWalkTypesOfTypeLocs() const { return false; }
1007 bool VisitAttributedStmt(AttributedStmt *S) {
1008 if (asFallThroughAttr(S))
1009 FallthroughStmts.insert(S);
1013 bool VisitSwitchStmt(SwitchStmt *S) {
1014 FoundSwitchStatements = true;
1018 // We don't want to traverse local type declarations. We analyze their
1019 // methods separately.
1020 bool TraverseDecl(Decl *D) { return true; }
1022 // We analyze lambda bodies separately. Skip them here.
1023 bool TraverseLambdaBody(LambdaExpr *LE) { return true; }
1027 static const AttributedStmt *asFallThroughAttr(const Stmt *S) {
1028 if (const AttributedStmt *AS = dyn_cast_or_null<AttributedStmt>(S)) {
1029 if (hasSpecificAttr<FallThroughAttr>(AS->getAttrs()))
1035 static const Stmt *getLastStmt(const CFGBlock &B) {
1036 if (const Stmt *Term = B.getTerminator())
1038 for (CFGBlock::const_reverse_iterator ElemIt = B.rbegin(),
1040 ElemIt != ElemEnd; ++ElemIt) {
1041 if (Optional<CFGStmt> CS = ElemIt->getAs<CFGStmt>())
1042 return CS->getStmt();
1044 // Workaround to detect a statement thrown out by CFGBuilder:
1045 // case X: {} case Y:
1046 // case X: ; case Y:
1047 if (const SwitchCase *SW = dyn_cast_or_null<SwitchCase>(B.getLabel()))
1048 if (!isa<SwitchCase>(SW->getSubStmt()))
1049 return SW->getSubStmt();
1054 bool FoundSwitchStatements;
1055 AttrStmts FallthroughStmts;
1057 llvm::SmallPtrSet<const CFGBlock *, 16> ReachableBlocks;
1061 static void DiagnoseSwitchLabelsFallthrough(Sema &S, AnalysisDeclContext &AC,
1063 // Only perform this analysis when using C++11. There is no good workflow
1064 // for this warning when not using C++11. There is no good way to silence
1065 // the warning (no attribute is available) unless we are using C++11's support
1066 // for generalized attributes. Once could use pragmas to silence the warning,
1067 // but as a general solution that is gross and not in the spirit of this
1070 // NOTE: This an intermediate solution. There are on-going discussions on
1071 // how to properly support this warning outside of C++11 with an annotation.
1072 if (!AC.getASTContext().getLangOpts().CPlusPlus11)
1075 FallthroughMapper FM(S);
1076 FM.TraverseStmt(AC.getBody());
1078 if (!FM.foundSwitchStatements())
1081 if (PerFunction && FM.getFallthroughStmts().empty())
1084 CFG *Cfg = AC.getCFG();
1089 FM.fillReachableBlocks(Cfg);
1091 for (CFG::reverse_iterator I = Cfg->rbegin(), E = Cfg->rend(); I != E; ++I) {
1092 const CFGBlock *B = *I;
1093 const Stmt *Label = B->getLabel();
1095 if (!Label || !isa<SwitchCase>(Label))
1100 if (!FM.checkFallThroughIntoBlock(*B, AnnotatedCnt))
1103 S.Diag(Label->getLocStart(),
1104 PerFunction ? diag::warn_unannotated_fallthrough_per_function
1105 : diag::warn_unannotated_fallthrough);
1107 if (!AnnotatedCnt) {
1108 SourceLocation L = Label->getLocStart();
1111 if (S.getLangOpts().CPlusPlus11) {
1112 const Stmt *Term = B->getTerminator();
1113 // Skip empty cases.
1114 while (B->empty() && !Term && B->succ_size() == 1) {
1115 B = *B->succ_begin();
1116 Term = B->getTerminator();
1118 if (!(B->empty() && Term && isa<BreakStmt>(Term))) {
1119 Preprocessor &PP = S.getPreprocessor();
1120 TokenValue Tokens[] = {
1121 tok::l_square, tok::l_square, PP.getIdentifierInfo("clang"),
1122 tok::coloncolon, PP.getIdentifierInfo("fallthrough"),
1123 tok::r_square, tok::r_square
1125 StringRef AnnotationSpelling = "[[clang::fallthrough]]";
1126 StringRef MacroName = PP.getLastMacroWithSpelling(L, Tokens);
1127 if (!MacroName.empty())
1128 AnnotationSpelling = MacroName;
1129 SmallString<64> TextToInsert(AnnotationSpelling);
1130 TextToInsert += "; ";
1131 S.Diag(L, diag::note_insert_fallthrough_fixit) <<
1132 AnnotationSpelling <<
1133 FixItHint::CreateInsertion(L, TextToInsert);
1136 S.Diag(L, diag::note_insert_break_fixit) <<
1137 FixItHint::CreateInsertion(L, "break; ");
1141 for (const auto *F : FM.getFallthroughStmts())
1142 S.Diag(F->getLocStart(), diag::warn_fallthrough_attr_invalid_placement);
1145 static bool isInLoop(const ASTContext &Ctx, const ParentMap &PM,
1150 switch (S->getStmtClass()) {
1151 case Stmt::ForStmtClass:
1152 case Stmt::WhileStmtClass:
1153 case Stmt::CXXForRangeStmtClass:
1154 case Stmt::ObjCForCollectionStmtClass:
1156 case Stmt::DoStmtClass: {
1157 const Expr *Cond = cast<DoStmt>(S)->getCond();
1159 if (!Cond->EvaluateAsInt(Val, Ctx))
1161 return Val.getBoolValue();
1166 } while ((S = PM.getParent(S)));
1172 static void diagnoseRepeatedUseOfWeak(Sema &S,
1173 const sema::FunctionScopeInfo *CurFn,
1175 const ParentMap &PM) {
1176 typedef sema::FunctionScopeInfo::WeakObjectProfileTy WeakObjectProfileTy;
1177 typedef sema::FunctionScopeInfo::WeakObjectUseMap WeakObjectUseMap;
1178 typedef sema::FunctionScopeInfo::WeakUseVector WeakUseVector;
1179 typedef std::pair<const Stmt *, WeakObjectUseMap::const_iterator>
1182 ASTContext &Ctx = S.getASTContext();
1184 const WeakObjectUseMap &WeakMap = CurFn->getWeakObjectUses();
1186 // Extract all weak objects that are referenced more than once.
1187 SmallVector<StmtUsesPair, 8> UsesByStmt;
1188 for (WeakObjectUseMap::const_iterator I = WeakMap.begin(), E = WeakMap.end();
1190 const WeakUseVector &Uses = I->second;
1192 // Find the first read of the weak object.
1193 WeakUseVector::const_iterator UI = Uses.begin(), UE = Uses.end();
1194 for ( ; UI != UE; ++UI) {
1199 // If there were only writes to this object, don't warn.
1203 // If there was only one read, followed by any number of writes, and the
1204 // read is not within a loop, don't warn. Additionally, don't warn in a
1205 // loop if the base object is a local variable -- local variables are often
1206 // changed in loops.
1207 if (UI == Uses.begin()) {
1208 WeakUseVector::const_iterator UI2 = UI;
1209 for (++UI2; UI2 != UE; ++UI2)
1210 if (UI2->isUnsafe())
1214 if (!isInLoop(Ctx, PM, UI->getUseExpr()))
1217 const WeakObjectProfileTy &Profile = I->first;
1218 if (!Profile.isExactProfile())
1221 const NamedDecl *Base = Profile.getBase();
1223 Base = Profile.getProperty();
1224 assert(Base && "A profile always has a base or property.");
1226 if (const VarDecl *BaseVar = dyn_cast<VarDecl>(Base))
1227 if (BaseVar->hasLocalStorage() && !isa<ParmVarDecl>(Base))
1232 UsesByStmt.push_back(StmtUsesPair(UI->getUseExpr(), I));
1235 if (UsesByStmt.empty())
1238 // Sort by first use so that we emit the warnings in a deterministic order.
1239 SourceManager &SM = S.getSourceManager();
1240 std::sort(UsesByStmt.begin(), UsesByStmt.end(),
1241 [&SM](const StmtUsesPair &LHS, const StmtUsesPair &RHS) {
1242 return SM.isBeforeInTranslationUnit(LHS.first->getLocStart(),
1243 RHS.first->getLocStart());
1246 // Classify the current code body for better warning text.
1247 // This enum should stay in sync with the cases in
1248 // warn_arc_repeated_use_of_weak and warn_arc_possible_repeated_use_of_weak.
1249 // FIXME: Should we use a common classification enum and the same set of
1250 // possibilities all throughout Sema?
1258 if (isa<sema::BlockScopeInfo>(CurFn))
1259 FunctionKind = Block;
1260 else if (isa<sema::LambdaScopeInfo>(CurFn))
1261 FunctionKind = Lambda;
1262 else if (isa<ObjCMethodDecl>(D))
1263 FunctionKind = Method;
1265 FunctionKind = Function;
1267 // Iterate through the sorted problems and emit warnings for each.
1268 for (const auto &P : UsesByStmt) {
1269 const Stmt *FirstRead = P.first;
1270 const WeakObjectProfileTy &Key = P.second->first;
1271 const WeakUseVector &Uses = P.second->second;
1273 // For complicated expressions like 'a.b.c' and 'x.b.c', WeakObjectProfileTy
1274 // may not contain enough information to determine that these are different
1275 // properties. We can only be 100% sure of a repeated use in certain cases,
1276 // and we adjust the diagnostic kind accordingly so that the less certain
1277 // case can be turned off if it is too noisy.
1279 if (Key.isExactProfile())
1280 DiagKind = diag::warn_arc_repeated_use_of_weak;
1282 DiagKind = diag::warn_arc_possible_repeated_use_of_weak;
1284 // Classify the weak object being accessed for better warning text.
1285 // This enum should stay in sync with the cases in
1286 // warn_arc_repeated_use_of_weak and warn_arc_possible_repeated_use_of_weak.
1294 const NamedDecl *D = Key.getProperty();
1295 if (isa<VarDecl>(D))
1296 ObjectKind = Variable;
1297 else if (isa<ObjCPropertyDecl>(D))
1298 ObjectKind = Property;
1299 else if (isa<ObjCMethodDecl>(D))
1300 ObjectKind = ImplicitProperty;
1301 else if (isa<ObjCIvarDecl>(D))
1304 llvm_unreachable("Unexpected weak object kind!");
1306 // Show the first time the object was read.
1307 S.Diag(FirstRead->getLocStart(), DiagKind)
1308 << int(ObjectKind) << D << int(FunctionKind)
1309 << FirstRead->getSourceRange();
1311 // Print all the other accesses as notes.
1312 for (const auto &Use : Uses) {
1313 if (Use.getUseExpr() == FirstRead)
1315 S.Diag(Use.getUseExpr()->getLocStart(),
1316 diag::note_arc_weak_also_accessed_here)
1317 << Use.getUseExpr()->getSourceRange();
1323 class UninitValsDiagReporter : public UninitVariablesHandler {
1325 typedef SmallVector<UninitUse, 2> UsesVec;
1326 typedef llvm::PointerIntPair<UsesVec *, 1, bool> MappedType;
1327 // Prefer using MapVector to DenseMap, so that iteration order will be
1328 // the same as insertion order. This is needed to obtain a deterministic
1329 // order of diagnostics when calling flushDiagnostics().
1330 typedef llvm::MapVector<const VarDecl *, MappedType> UsesMap;
1334 UninitValsDiagReporter(Sema &S) : S(S), uses(nullptr) {}
1335 ~UninitValsDiagReporter() {
1339 MappedType &getUses(const VarDecl *vd) {
1341 uses = new UsesMap();
1343 MappedType &V = (*uses)[vd];
1344 if (!V.getPointer())
1345 V.setPointer(new UsesVec());
1350 void handleUseOfUninitVariable(const VarDecl *vd,
1351 const UninitUse &use) override {
1352 getUses(vd).getPointer()->push_back(use);
1355 void handleSelfInit(const VarDecl *vd) override {
1356 getUses(vd).setInt(true);
1359 void flushDiagnostics() {
1363 for (const auto &P : *uses) {
1364 const VarDecl *vd = P.first;
1365 const MappedType &V = P.second;
1367 UsesVec *vec = V.getPointer();
1368 bool hasSelfInit = V.getInt();
1370 // Specially handle the case where we have uses of an uninitialized
1371 // variable, but the root cause is an idiomatic self-init. We want
1372 // to report the diagnostic at the self-init since that is the root cause.
1373 if (!vec->empty() && hasSelfInit && hasAlwaysUninitializedUse(vec))
1374 DiagnoseUninitializedUse(S, vd,
1375 UninitUse(vd->getInit()->IgnoreParenCasts(),
1376 /* isAlwaysUninit */ true),
1377 /* alwaysReportSelfInit */ true);
1379 // Sort the uses by their SourceLocations. While not strictly
1380 // guaranteed to produce them in line/column order, this will provide
1381 // a stable ordering.
1382 std::sort(vec->begin(), vec->end(),
1383 [](const UninitUse &a, const UninitUse &b) {
1384 // Prefer a more confident report over a less confident one.
1385 if (a.getKind() != b.getKind())
1386 return a.getKind() > b.getKind();
1387 return a.getUser()->getLocStart() < b.getUser()->getLocStart();
1390 for (const auto &U : *vec) {
1391 // If we have self-init, downgrade all uses to 'may be uninitialized'.
1392 UninitUse Use = hasSelfInit ? UninitUse(U.getUser(), false) : U;
1394 if (DiagnoseUninitializedUse(S, vd, Use))
1395 // Skip further diagnostics for this variable. We try to warn only
1396 // on the first point at which a variable is used uninitialized.
1401 // Release the uses vector.
1408 static bool hasAlwaysUninitializedUse(const UsesVec* vec) {
1409 return std::any_of(vec->begin(), vec->end(), [](const UninitUse &U) {
1410 return U.getKind() == UninitUse::Always ||
1411 U.getKind() == UninitUse::AfterCall ||
1412 U.getKind() == UninitUse::AfterDecl;
1420 typedef SmallVector<PartialDiagnosticAt, 1> OptionalNotes;
1421 typedef std::pair<PartialDiagnosticAt, OptionalNotes> DelayedDiag;
1422 typedef std::list<DelayedDiag> DiagList;
1424 struct SortDiagBySourceLocation {
1426 SortDiagBySourceLocation(SourceManager &SM) : SM(SM) {}
1428 bool operator()(const DelayedDiag &left, const DelayedDiag &right) {
1429 // Although this call will be slow, this is only called when outputting
1430 // multiple warnings.
1431 return SM.isBeforeInTranslationUnit(left.first.first, right.first.first);
1436 //===----------------------------------------------------------------------===//
1438 //===----------------------------------------------------------------------===//
1440 namespace threadSafety {
1442 class ThreadSafetyReporter : public clang::threadSafety::ThreadSafetyHandler {
1445 SourceLocation FunLocation, FunEndLocation;
1447 const FunctionDecl *CurrentFunction;
1450 OptionalNotes getNotes() const {
1451 if (Verbose && CurrentFunction) {
1452 PartialDiagnosticAt FNote(CurrentFunction->getBody()->getLocStart(),
1453 S.PDiag(diag::note_thread_warning_in_fun)
1454 << CurrentFunction->getNameAsString());
1455 return OptionalNotes(1, FNote);
1457 return OptionalNotes();
1460 OptionalNotes getNotes(const PartialDiagnosticAt &Note) const {
1461 OptionalNotes ONS(1, Note);
1462 if (Verbose && CurrentFunction) {
1463 PartialDiagnosticAt FNote(CurrentFunction->getBody()->getLocStart(),
1464 S.PDiag(diag::note_thread_warning_in_fun)
1465 << CurrentFunction->getNameAsString());
1466 ONS.push_back(FNote);
1471 OptionalNotes getNotes(const PartialDiagnosticAt &Note1,
1472 const PartialDiagnosticAt &Note2) const {
1474 ONS.push_back(Note1);
1475 ONS.push_back(Note2);
1476 if (Verbose && CurrentFunction) {
1477 PartialDiagnosticAt FNote(CurrentFunction->getBody()->getLocStart(),
1478 S.PDiag(diag::note_thread_warning_in_fun)
1479 << CurrentFunction->getNameAsString());
1480 ONS.push_back(FNote);
1486 void warnLockMismatch(unsigned DiagID, StringRef Kind, Name LockName,
1487 SourceLocation Loc) {
1488 // Gracefully handle rare cases when the analysis can't get a more
1489 // precise source location.
1492 PartialDiagnosticAt Warning(Loc, S.PDiag(DiagID) << Kind << LockName);
1493 Warnings.push_back(DelayedDiag(Warning, getNotes()));
1497 ThreadSafetyReporter(Sema &S, SourceLocation FL, SourceLocation FEL)
1498 : S(S), FunLocation(FL), FunEndLocation(FEL),
1499 CurrentFunction(nullptr), Verbose(false) {}
1501 void setVerbose(bool b) { Verbose = b; }
1503 /// \brief Emit all buffered diagnostics in order of sourcelocation.
1504 /// We need to output diagnostics produced while iterating through
1505 /// the lockset in deterministic order, so this function orders diagnostics
1506 /// and outputs them.
1507 void emitDiagnostics() {
1508 Warnings.sort(SortDiagBySourceLocation(S.getSourceManager()));
1509 for (const auto &Diag : Warnings) {
1510 S.Diag(Diag.first.first, Diag.first.second);
1511 for (const auto &Note : Diag.second)
1512 S.Diag(Note.first, Note.second);
1516 void handleInvalidLockExp(StringRef Kind, SourceLocation Loc) override {
1517 PartialDiagnosticAt Warning(Loc, S.PDiag(diag::warn_cannot_resolve_lock)
1519 Warnings.push_back(DelayedDiag(Warning, getNotes()));
1522 void handleUnmatchedUnlock(StringRef Kind, Name LockName,
1523 SourceLocation Loc) override {
1524 warnLockMismatch(diag::warn_unlock_but_no_lock, Kind, LockName, Loc);
1527 void handleIncorrectUnlockKind(StringRef Kind, Name LockName,
1528 LockKind Expected, LockKind Received,
1529 SourceLocation Loc) override {
1530 if (Loc.isInvalid())
1532 PartialDiagnosticAt Warning(Loc, S.PDiag(diag::warn_unlock_kind_mismatch)
1533 << Kind << LockName << Received
1535 Warnings.push_back(DelayedDiag(Warning, getNotes()));
1538 void handleDoubleLock(StringRef Kind, Name LockName, SourceLocation Loc) override {
1539 warnLockMismatch(diag::warn_double_lock, Kind, LockName, Loc);
1542 void handleMutexHeldEndOfScope(StringRef Kind, Name LockName,
1543 SourceLocation LocLocked,
1544 SourceLocation LocEndOfScope,
1545 LockErrorKind LEK) override {
1546 unsigned DiagID = 0;
1548 case LEK_LockedSomePredecessors:
1549 DiagID = diag::warn_lock_some_predecessors;
1551 case LEK_LockedSomeLoopIterations:
1552 DiagID = diag::warn_expecting_lock_held_on_loop;
1554 case LEK_LockedAtEndOfFunction:
1555 DiagID = diag::warn_no_unlock;
1557 case LEK_NotLockedAtEndOfFunction:
1558 DiagID = diag::warn_expecting_locked;
1561 if (LocEndOfScope.isInvalid())
1562 LocEndOfScope = FunEndLocation;
1564 PartialDiagnosticAt Warning(LocEndOfScope, S.PDiag(DiagID) << Kind
1566 if (LocLocked.isValid()) {
1567 PartialDiagnosticAt Note(LocLocked, S.PDiag(diag::note_locked_here)
1569 Warnings.push_back(DelayedDiag(Warning, getNotes(Note)));
1572 Warnings.push_back(DelayedDiag(Warning, getNotes()));
1575 void handleExclusiveAndShared(StringRef Kind, Name LockName,
1576 SourceLocation Loc1,
1577 SourceLocation Loc2) override {
1578 PartialDiagnosticAt Warning(Loc1,
1579 S.PDiag(diag::warn_lock_exclusive_and_shared)
1580 << Kind << LockName);
1581 PartialDiagnosticAt Note(Loc2, S.PDiag(diag::note_lock_exclusive_and_shared)
1582 << Kind << LockName);
1583 Warnings.push_back(DelayedDiag(Warning, getNotes(Note)));
1586 void handleNoMutexHeld(StringRef Kind, const NamedDecl *D,
1587 ProtectedOperationKind POK, AccessKind AK,
1588 SourceLocation Loc) override {
1589 assert((POK == POK_VarAccess || POK == POK_VarDereference) &&
1590 "Only works for variables");
1591 unsigned DiagID = POK == POK_VarAccess?
1592 diag::warn_variable_requires_any_lock:
1593 diag::warn_var_deref_requires_any_lock;
1594 PartialDiagnosticAt Warning(Loc, S.PDiag(DiagID)
1595 << D->getNameAsString() << getLockKindFromAccessKind(AK));
1596 Warnings.push_back(DelayedDiag(Warning, getNotes()));
1599 void handleMutexNotHeld(StringRef Kind, const NamedDecl *D,
1600 ProtectedOperationKind POK, Name LockName,
1601 LockKind LK, SourceLocation Loc,
1602 Name *PossibleMatch) override {
1603 unsigned DiagID = 0;
1604 if (PossibleMatch) {
1607 DiagID = diag::warn_variable_requires_lock_precise;
1609 case POK_VarDereference:
1610 DiagID = diag::warn_var_deref_requires_lock_precise;
1612 case POK_FunctionCall:
1613 DiagID = diag::warn_fun_requires_lock_precise;
1616 DiagID = diag::warn_guarded_pass_by_reference;
1618 case POK_PtPassByRef:
1619 DiagID = diag::warn_pt_guarded_pass_by_reference;
1622 PartialDiagnosticAt Warning(Loc, S.PDiag(DiagID) << Kind
1623 << D->getNameAsString()
1625 PartialDiagnosticAt Note(Loc, S.PDiag(diag::note_found_mutex_near_match)
1627 if (Verbose && POK == POK_VarAccess) {
1628 PartialDiagnosticAt VNote(D->getLocation(),
1629 S.PDiag(diag::note_guarded_by_declared_here)
1630 << D->getNameAsString());
1631 Warnings.push_back(DelayedDiag(Warning, getNotes(Note, VNote)));
1633 Warnings.push_back(DelayedDiag(Warning, getNotes(Note)));
1637 DiagID = diag::warn_variable_requires_lock;
1639 case POK_VarDereference:
1640 DiagID = diag::warn_var_deref_requires_lock;
1642 case POK_FunctionCall:
1643 DiagID = diag::warn_fun_requires_lock;
1646 DiagID = diag::warn_guarded_pass_by_reference;
1648 case POK_PtPassByRef:
1649 DiagID = diag::warn_pt_guarded_pass_by_reference;
1652 PartialDiagnosticAt Warning(Loc, S.PDiag(DiagID) << Kind
1653 << D->getNameAsString()
1655 if (Verbose && POK == POK_VarAccess) {
1656 PartialDiagnosticAt Note(D->getLocation(),
1657 S.PDiag(diag::note_guarded_by_declared_here)
1658 << D->getNameAsString());
1659 Warnings.push_back(DelayedDiag(Warning, getNotes(Note)));
1661 Warnings.push_back(DelayedDiag(Warning, getNotes()));
1666 virtual void handleNegativeNotHeld(StringRef Kind, Name LockName, Name Neg,
1667 SourceLocation Loc) override {
1668 PartialDiagnosticAt Warning(Loc,
1669 S.PDiag(diag::warn_acquire_requires_negative_cap)
1670 << Kind << LockName << Neg);
1671 Warnings.push_back(DelayedDiag(Warning, getNotes()));
1675 void handleFunExcludesLock(StringRef Kind, Name FunName, Name LockName,
1676 SourceLocation Loc) override {
1677 PartialDiagnosticAt Warning(Loc, S.PDiag(diag::warn_fun_excludes_mutex)
1678 << Kind << FunName << LockName);
1679 Warnings.push_back(DelayedDiag(Warning, getNotes()));
1682 void enterFunction(const FunctionDecl* FD) override {
1683 CurrentFunction = FD;
1686 void leaveFunction(const FunctionDecl* FD) override {
1687 CurrentFunction = 0;
1694 //===----------------------------------------------------------------------===//
1696 //===----------------------------------------------------------------------===//
1699 namespace consumed {
1701 class ConsumedWarningsHandler : public ConsumedWarningsHandlerBase {
1708 ConsumedWarningsHandler(Sema &S) : S(S) {}
1710 void emitDiagnostics() override {
1711 Warnings.sort(SortDiagBySourceLocation(S.getSourceManager()));
1712 for (const auto &Diag : Warnings) {
1713 S.Diag(Diag.first.first, Diag.first.second);
1714 for (const auto &Note : Diag.second)
1715 S.Diag(Note.first, Note.second);
1719 void warnLoopStateMismatch(SourceLocation Loc,
1720 StringRef VariableName) override {
1721 PartialDiagnosticAt Warning(Loc, S.PDiag(diag::warn_loop_state_mismatch) <<
1724 Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
1727 void warnParamReturnTypestateMismatch(SourceLocation Loc,
1728 StringRef VariableName,
1729 StringRef ExpectedState,
1730 StringRef ObservedState) override {
1732 PartialDiagnosticAt Warning(Loc, S.PDiag(
1733 diag::warn_param_return_typestate_mismatch) << VariableName <<
1734 ExpectedState << ObservedState);
1736 Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
1739 void warnParamTypestateMismatch(SourceLocation Loc, StringRef ExpectedState,
1740 StringRef ObservedState) override {
1742 PartialDiagnosticAt Warning(Loc, S.PDiag(
1743 diag::warn_param_typestate_mismatch) << ExpectedState << ObservedState);
1745 Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
1748 void warnReturnTypestateForUnconsumableType(SourceLocation Loc,
1749 StringRef TypeName) override {
1750 PartialDiagnosticAt Warning(Loc, S.PDiag(
1751 diag::warn_return_typestate_for_unconsumable_type) << TypeName);
1753 Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
1756 void warnReturnTypestateMismatch(SourceLocation Loc, StringRef ExpectedState,
1757 StringRef ObservedState) override {
1759 PartialDiagnosticAt Warning(Loc, S.PDiag(
1760 diag::warn_return_typestate_mismatch) << ExpectedState << ObservedState);
1762 Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
1765 void warnUseOfTempInInvalidState(StringRef MethodName, StringRef State,
1766 SourceLocation Loc) override {
1768 PartialDiagnosticAt Warning(Loc, S.PDiag(
1769 diag::warn_use_of_temp_in_invalid_state) << MethodName << State);
1771 Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
1774 void warnUseInInvalidState(StringRef MethodName, StringRef VariableName,
1775 StringRef State, SourceLocation Loc) override {
1777 PartialDiagnosticAt Warning(Loc, S.PDiag(diag::warn_use_in_invalid_state) <<
1778 MethodName << VariableName << State);
1780 Warnings.push_back(DelayedDiag(Warning, OptionalNotes()));
1785 //===----------------------------------------------------------------------===//
1786 // AnalysisBasedWarnings - Worker object used by Sema to execute analysis-based
1787 // warnings on a function, method, or block.
1788 //===----------------------------------------------------------------------===//
1790 clang::sema::AnalysisBasedWarnings::Policy::Policy() {
1791 enableCheckFallThrough = 1;
1792 enableCheckUnreachable = 0;
1793 enableThreadSafetyAnalysis = 0;
1794 enableConsumedAnalysis = 0;
1797 static unsigned isEnabled(DiagnosticsEngine &D, unsigned diag) {
1798 return (unsigned)!D.isIgnored(diag, SourceLocation());
1801 clang::sema::AnalysisBasedWarnings::AnalysisBasedWarnings(Sema &s)
1803 NumFunctionsAnalyzed(0),
1804 NumFunctionsWithBadCFGs(0),
1806 MaxCFGBlocksPerFunction(0),
1807 NumUninitAnalysisFunctions(0),
1808 NumUninitAnalysisVariables(0),
1809 MaxUninitAnalysisVariablesPerFunction(0),
1810 NumUninitAnalysisBlockVisits(0),
1811 MaxUninitAnalysisBlockVisitsPerFunction(0) {
1813 using namespace diag;
1814 DiagnosticsEngine &D = S.getDiagnostics();
1816 DefaultPolicy.enableCheckUnreachable =
1817 isEnabled(D, warn_unreachable) ||
1818 isEnabled(D, warn_unreachable_break) ||
1819 isEnabled(D, warn_unreachable_return) ||
1820 isEnabled(D, warn_unreachable_loop_increment);
1822 DefaultPolicy.enableThreadSafetyAnalysis =
1823 isEnabled(D, warn_double_lock);
1825 DefaultPolicy.enableConsumedAnalysis =
1826 isEnabled(D, warn_use_in_invalid_state);
1829 static void flushDiagnostics(Sema &S, const sema::FunctionScopeInfo *fscope) {
1830 for (const auto &D : fscope->PossiblyUnreachableDiags)
1831 S.Diag(D.Loc, D.PD);
1835 AnalysisBasedWarnings::IssueWarnings(sema::AnalysisBasedWarnings::Policy P,
1836 sema::FunctionScopeInfo *fscope,
1837 const Decl *D, const BlockExpr *blkExpr) {
1839 // We avoid doing analysis-based warnings when there are errors for
1841 // (1) The CFGs often can't be constructed (if the body is invalid), so
1842 // don't bother trying.
1843 // (2) The code already has problems; running the analysis just takes more
1845 DiagnosticsEngine &Diags = S.getDiagnostics();
1847 // Do not do any analysis for declarations in system headers if we are
1848 // going to just ignore them.
1849 if (Diags.getSuppressSystemWarnings() &&
1850 S.SourceMgr.isInSystemHeader(D->getLocation()))
1853 // For code in dependent contexts, we'll do this at instantiation time.
1854 if (cast<DeclContext>(D)->isDependentContext())
1857 if (Diags.hasUncompilableErrorOccurred() || Diags.hasFatalErrorOccurred()) {
1858 // Flush out any possibly unreachable diagnostics.
1859 flushDiagnostics(S, fscope);
1863 const Stmt *Body = D->getBody();
1866 // Construct the analysis context with the specified CFG build options.
1867 AnalysisDeclContext AC(/* AnalysisDeclContextManager */ nullptr, D);
1869 // Don't generate EH edges for CallExprs as we'd like to avoid the n^2
1870 // explosion for destructors that can result and the compile time hit.
1871 AC.getCFGBuildOptions().PruneTriviallyFalseEdges = true;
1872 AC.getCFGBuildOptions().AddEHEdges = false;
1873 AC.getCFGBuildOptions().AddInitializers = true;
1874 AC.getCFGBuildOptions().AddImplicitDtors = true;
1875 AC.getCFGBuildOptions().AddTemporaryDtors = true;
1876 AC.getCFGBuildOptions().AddCXXNewAllocator = false;
1878 // Force that certain expressions appear as CFGElements in the CFG. This
1879 // is used to speed up various analyses.
1880 // FIXME: This isn't the right factoring. This is here for initial
1881 // prototyping, but we need a way for analyses to say what expressions they
1882 // expect to always be CFGElements and then fill in the BuildOptions
1883 // appropriately. This is essentially a layering violation.
1884 if (P.enableCheckUnreachable || P.enableThreadSafetyAnalysis ||
1885 P.enableConsumedAnalysis) {
1886 // Unreachable code analysis and thread safety require a linearized CFG.
1887 AC.getCFGBuildOptions().setAllAlwaysAdd();
1890 AC.getCFGBuildOptions()
1891 .setAlwaysAdd(Stmt::BinaryOperatorClass)
1892 .setAlwaysAdd(Stmt::CompoundAssignOperatorClass)
1893 .setAlwaysAdd(Stmt::BlockExprClass)
1894 .setAlwaysAdd(Stmt::CStyleCastExprClass)
1895 .setAlwaysAdd(Stmt::DeclRefExprClass)
1896 .setAlwaysAdd(Stmt::ImplicitCastExprClass)
1897 .setAlwaysAdd(Stmt::UnaryOperatorClass)
1898 .setAlwaysAdd(Stmt::AttributedStmtClass);
1901 // Install the logical handler for -Wtautological-overlap-compare
1902 std::unique_ptr<LogicalErrorHandler> LEH;
1903 if (!Diags.isIgnored(diag::warn_tautological_overlap_comparison,
1904 D->getLocStart())) {
1905 LEH.reset(new LogicalErrorHandler(S));
1906 AC.getCFGBuildOptions().Observer = LEH.get();
1909 // Emit delayed diagnostics.
1910 if (!fscope->PossiblyUnreachableDiags.empty()) {
1911 bool analyzed = false;
1913 // Register the expressions with the CFGBuilder.
1914 for (const auto &D : fscope->PossiblyUnreachableDiags) {
1916 AC.registerForcedBlockExpression(D.stmt);
1921 for (const auto &D : fscope->PossiblyUnreachableDiags) {
1922 bool processed = false;
1924 const CFGBlock *block = AC.getBlockForRegisteredExpression(D.stmt);
1925 CFGReverseBlockReachabilityAnalysis *cra =
1926 AC.getCFGReachablityAnalysis();
1927 // FIXME: We should be able to assert that block is non-null, but
1928 // the CFG analysis can skip potentially-evaluated expressions in
1929 // edge cases; see test/Sema/vla-2.c.
1931 // Can this block be reached from the entrance?
1932 if (cra->isReachable(&AC.getCFG()->getEntry(), block))
1933 S.Diag(D.Loc, D.PD);
1938 // Emit the warning anyway if we cannot map to a basic block.
1939 S.Diag(D.Loc, D.PD);
1945 flushDiagnostics(S, fscope);
1949 // Warning: check missing 'return'
1950 if (P.enableCheckFallThrough) {
1951 const CheckFallThroughDiagnostics &CD =
1952 (isa<BlockDecl>(D) ? CheckFallThroughDiagnostics::MakeForBlock()
1953 : (isa<CXXMethodDecl>(D) &&
1954 cast<CXXMethodDecl>(D)->getOverloadedOperator() == OO_Call &&
1955 cast<CXXMethodDecl>(D)->getParent()->isLambda())
1956 ? CheckFallThroughDiagnostics::MakeForLambda()
1957 : CheckFallThroughDiagnostics::MakeForFunction(D));
1958 CheckFallThroughForBody(S, D, Body, blkExpr, CD, AC);
1961 // Warning: check for unreachable code
1962 if (P.enableCheckUnreachable) {
1963 // Only check for unreachable code on non-template instantiations.
1964 // Different template instantiations can effectively change the control-flow
1965 // and it is very difficult to prove that a snippet of code in a template
1966 // is unreachable for all instantiations.
1967 bool isTemplateInstantiation = false;
1968 if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(D))
1969 isTemplateInstantiation = Function->isTemplateInstantiation();
1970 if (!isTemplateInstantiation)
1971 CheckUnreachable(S, AC);
1974 // Check for thread safety violations
1975 if (P.enableThreadSafetyAnalysis) {
1976 SourceLocation FL = AC.getDecl()->getLocation();
1977 SourceLocation FEL = AC.getDecl()->getLocEnd();
1978 threadSafety::ThreadSafetyReporter Reporter(S, FL, FEL);
1979 if (!Diags.isIgnored(diag::warn_thread_safety_beta, D->getLocStart()))
1980 Reporter.setIssueBetaWarnings(true);
1981 if (!Diags.isIgnored(diag::warn_thread_safety_verbose, D->getLocStart()))
1982 Reporter.setVerbose(true);
1984 threadSafety::runThreadSafetyAnalysis(AC, Reporter);
1985 Reporter.emitDiagnostics();
1988 // Check for violations of consumed properties.
1989 if (P.enableConsumedAnalysis) {
1990 consumed::ConsumedWarningsHandler WarningHandler(S);
1991 consumed::ConsumedAnalyzer Analyzer(WarningHandler);
1995 if (!Diags.isIgnored(diag::warn_uninit_var, D->getLocStart()) ||
1996 !Diags.isIgnored(diag::warn_sometimes_uninit_var, D->getLocStart()) ||
1997 !Diags.isIgnored(diag::warn_maybe_uninit_var, D->getLocStart())) {
1998 if (CFG *cfg = AC.getCFG()) {
1999 UninitValsDiagReporter reporter(S);
2000 UninitVariablesAnalysisStats stats;
2001 std::memset(&stats, 0, sizeof(UninitVariablesAnalysisStats));
2002 runUninitializedVariablesAnalysis(*cast<DeclContext>(D), *cfg, AC,
2005 if (S.CollectStats && stats.NumVariablesAnalyzed > 0) {
2006 ++NumUninitAnalysisFunctions;
2007 NumUninitAnalysisVariables += stats.NumVariablesAnalyzed;
2008 NumUninitAnalysisBlockVisits += stats.NumBlockVisits;
2009 MaxUninitAnalysisVariablesPerFunction =
2010 std::max(MaxUninitAnalysisVariablesPerFunction,
2011 stats.NumVariablesAnalyzed);
2012 MaxUninitAnalysisBlockVisitsPerFunction =
2013 std::max(MaxUninitAnalysisBlockVisitsPerFunction,
2014 stats.NumBlockVisits);
2019 bool FallThroughDiagFull =
2020 !Diags.isIgnored(diag::warn_unannotated_fallthrough, D->getLocStart());
2021 bool FallThroughDiagPerFunction = !Diags.isIgnored(
2022 diag::warn_unannotated_fallthrough_per_function, D->getLocStart());
2023 if (FallThroughDiagFull || FallThroughDiagPerFunction) {
2024 DiagnoseSwitchLabelsFallthrough(S, AC, !FallThroughDiagFull);
2027 if (S.getLangOpts().ObjCARCWeak &&
2028 !Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, D->getLocStart()))
2029 diagnoseRepeatedUseOfWeak(S, fscope, D, AC.getParentMap());
2032 // Check for infinite self-recursion in functions
2033 if (!Diags.isIgnored(diag::warn_infinite_recursive_function,
2034 D->getLocStart())) {
2035 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
2036 checkRecursiveFunction(S, FD, Body, AC);
2040 // If none of the previous checks caused a CFG build, trigger one here
2041 // for -Wtautological-overlap-compare
2042 if (!Diags.isIgnored(diag::warn_tautological_overlap_comparison,
2043 D->getLocStart())) {
2047 // Collect statistics about the CFG if it was built.
2048 if (S.CollectStats && AC.isCFGBuilt()) {
2049 ++NumFunctionsAnalyzed;
2050 if (CFG *cfg = AC.getCFG()) {
2051 // If we successfully built a CFG for this context, record some more
2052 // detail information about it.
2053 NumCFGBlocks += cfg->getNumBlockIDs();
2054 MaxCFGBlocksPerFunction = std::max(MaxCFGBlocksPerFunction,
2055 cfg->getNumBlockIDs());
2057 ++NumFunctionsWithBadCFGs;
2062 void clang::sema::AnalysisBasedWarnings::PrintStats() const {
2063 llvm::errs() << "\n*** Analysis Based Warnings Stats:\n";
2065 unsigned NumCFGsBuilt = NumFunctionsAnalyzed - NumFunctionsWithBadCFGs;
2066 unsigned AvgCFGBlocksPerFunction =
2067 !NumCFGsBuilt ? 0 : NumCFGBlocks/NumCFGsBuilt;
2068 llvm::errs() << NumFunctionsAnalyzed << " functions analyzed ("
2069 << NumFunctionsWithBadCFGs << " w/o CFGs).\n"
2070 << " " << NumCFGBlocks << " CFG blocks built.\n"
2071 << " " << AvgCFGBlocksPerFunction
2072 << " average CFG blocks per function.\n"
2073 << " " << MaxCFGBlocksPerFunction
2074 << " max CFG blocks per function.\n";
2076 unsigned AvgUninitVariablesPerFunction = !NumUninitAnalysisFunctions ? 0
2077 : NumUninitAnalysisVariables/NumUninitAnalysisFunctions;
2078 unsigned AvgUninitBlockVisitsPerFunction = !NumUninitAnalysisFunctions ? 0
2079 : NumUninitAnalysisBlockVisits/NumUninitAnalysisFunctions;
2080 llvm::errs() << NumUninitAnalysisFunctions
2081 << " functions analyzed for uninitialiazed variables\n"
2082 << " " << NumUninitAnalysisVariables << " variables analyzed.\n"
2083 << " " << AvgUninitVariablesPerFunction
2084 << " average variables per function.\n"
2085 << " " << MaxUninitAnalysisVariablesPerFunction
2086 << " max variables per function.\n"
2087 << " " << NumUninitAnalysisBlockVisits << " block visits.\n"
2088 << " " << AvgUninitBlockVisitsPerFunction
2089 << " average block visits per function.\n"
2090 << " " << MaxUninitAnalysisBlockVisitsPerFunction
2091 << " max block visits per function.\n";