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/CXXInheritance.h"
19 #include "clang/AST/DeclObjC.h"
20 #include "clang/AST/EvaluatedExprVisitor.h"
21 #include "clang/AST/ExprCXX.h"
22 #include "clang/AST/ExprObjC.h"
23 #include "clang/AST/RecursiveASTVisitor.h"
24 #include "clang/AST/StmtCXX.h"
25 #include "clang/AST/StmtObjC.h"
26 #include "clang/AST/TypeLoc.h"
27 #include "clang/AST/TypeOrdering.h"
28 #include "clang/Lex/Preprocessor.h"
29 #include "clang/Sema/Initialization.h"
30 #include "clang/Sema/Lookup.h"
31 #include "clang/Sema/Scope.h"
32 #include "clang/Sema/ScopeInfo.h"
33 #include "llvm/ADT/ArrayRef.h"
34 #include "llvm/ADT/DenseMap.h"
35 #include "llvm/ADT/STLExtras.h"
36 #include "llvm/ADT/SmallPtrSet.h"
37 #include "llvm/ADT/SmallString.h"
38 #include "llvm/ADT/SmallVector.h"
39 using namespace clang;
42 StmtResult Sema::ActOnExprStmt(ExprResult FE) {
46 FE = ActOnFinishFullExpr(FE.get(), FE.get()->getExprLoc(),
47 /*DiscardedValue*/ true);
51 // C99 6.8.3p2: The expression in an expression statement is evaluated as a
52 // void expression for its side effects. Conversion to void allows any
53 // operand, even incomplete types.
55 // Same thing in for stmt first clause (when expr) and third clause.
56 return StmtResult(FE.getAs<Stmt>());
60 StmtResult Sema::ActOnExprStmtError() {
61 DiscardCleanupsInEvaluationContext();
65 StmtResult Sema::ActOnNullStmt(SourceLocation SemiLoc,
66 bool HasLeadingEmptyMacro) {
67 return new (Context) NullStmt(SemiLoc, HasLeadingEmptyMacro);
70 StmtResult Sema::ActOnDeclStmt(DeclGroupPtrTy dg, SourceLocation StartLoc,
71 SourceLocation EndLoc) {
72 DeclGroupRef DG = dg.get();
74 // If we have an invalid decl, just return an error.
75 if (DG.isNull()) return StmtError();
77 return new (Context) DeclStmt(DG, StartLoc, EndLoc);
80 void Sema::ActOnForEachDeclStmt(DeclGroupPtrTy dg) {
81 DeclGroupRef DG = dg.get();
83 // If we don't have a declaration, or we have an invalid declaration,
85 if (DG.isNull() || !DG.isSingleDecl())
88 Decl *decl = DG.getSingleDecl();
89 if (!decl || decl->isInvalidDecl())
92 // Only variable declarations are permitted.
93 VarDecl *var = dyn_cast<VarDecl>(decl);
95 Diag(decl->getLocation(), diag::err_non_variable_decl_in_for);
96 decl->setInvalidDecl();
100 // foreach variables are never actually initialized in the way that
101 // the parser came up with.
102 var->setInit(nullptr);
104 // In ARC, we don't need to retain the iteration variable of a fast
105 // enumeration loop. Rather than actually trying to catch that
106 // during declaration processing, we remove the consequences here.
107 if (getLangOpts().ObjCAutoRefCount) {
108 QualType type = var->getType();
110 // Only do this if we inferred the lifetime. Inferred lifetime
111 // will show up as a local qualifier because explicit lifetime
112 // should have shown up as an AttributedType instead.
113 if (type.getLocalQualifiers().getObjCLifetime() == Qualifiers::OCL_Strong) {
114 // Add 'const' and mark the variable as pseudo-strong.
115 var->setType(type.withConst());
116 var->setARCPseudoStrong(true);
121 /// \brief Diagnose unused comparisons, both builtin and overloaded operators.
122 /// For '==' and '!=', suggest fixits for '=' or '|='.
124 /// Adding a cast to void (or other expression wrappers) will prevent the
125 /// warning from firing.
126 static bool DiagnoseUnusedComparison(Sema &S, const Expr *E) {
128 bool IsNotEqual, CanAssign, IsRelational;
130 if (const BinaryOperator *Op = dyn_cast<BinaryOperator>(E)) {
131 if (!Op->isComparisonOp())
134 IsRelational = Op->isRelationalOp();
135 Loc = Op->getOperatorLoc();
136 IsNotEqual = Op->getOpcode() == BO_NE;
137 CanAssign = Op->getLHS()->IgnoreParenImpCasts()->isLValue();
138 } else if (const CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(E)) {
139 switch (Op->getOperator()) {
143 case OO_ExclaimEqual:
144 IsRelational = false;
148 case OO_GreaterEqual:
154 Loc = Op->getOperatorLoc();
155 IsNotEqual = Op->getOperator() == OO_ExclaimEqual;
156 CanAssign = Op->getArg(0)->IgnoreParenImpCasts()->isLValue();
158 // Not a typo-prone comparison.
162 // Suppress warnings when the operator, suspicious as it may be, comes from
163 // a macro expansion.
164 if (S.SourceMgr.isMacroBodyExpansion(Loc))
167 S.Diag(Loc, diag::warn_unused_comparison)
168 << (unsigned)IsRelational << (unsigned)IsNotEqual << E->getSourceRange();
170 // If the LHS is a plausible entity to assign to, provide a fixit hint to
171 // correct common typos.
172 if (!IsRelational && CanAssign) {
174 S.Diag(Loc, diag::note_inequality_comparison_to_or_assign)
175 << FixItHint::CreateReplacement(Loc, "|=");
177 S.Diag(Loc, diag::note_equality_comparison_to_assign)
178 << FixItHint::CreateReplacement(Loc, "=");
184 void Sema::DiagnoseUnusedExprResult(const Stmt *S) {
185 if (const LabelStmt *Label = dyn_cast_or_null<LabelStmt>(S))
186 return DiagnoseUnusedExprResult(Label->getSubStmt());
188 const Expr *E = dyn_cast_or_null<Expr>(S);
192 // If we are in an unevaluated expression context, then there can be no unused
193 // results because the results aren't expected to be used in the first place.
194 if (isUnevaluatedContext())
197 SourceLocation ExprLoc = E->IgnoreParens()->getExprLoc();
198 // In most cases, we don't want to warn if the expression is written in a
199 // macro body, or if the macro comes from a system header. If the offending
200 // expression is a call to a function with the warn_unused_result attribute,
201 // we warn no matter the location. Because of the order in which the various
202 // checks need to happen, we factor out the macro-related test here.
203 bool ShouldSuppress =
204 SourceMgr.isMacroBodyExpansion(ExprLoc) ||
205 SourceMgr.isInSystemMacro(ExprLoc);
207 const Expr *WarnExpr;
210 if (!E->isUnusedResultAWarning(WarnExpr, Loc, R1, R2, Context))
213 // If this is a GNU statement expression expanded from a macro, it is probably
214 // unused because it is a function-like macro that can be used as either an
215 // expression or statement. Don't warn, because it is almost certainly a
217 if (isa<StmtExpr>(E) && Loc.isMacroID())
220 // Okay, we have an unused result. Depending on what the base expression is,
221 // we might want to make a more specific diagnostic. Check for one of these
223 unsigned DiagID = diag::warn_unused_expr;
224 if (const ExprWithCleanups *Temps = dyn_cast<ExprWithCleanups>(E))
225 E = Temps->getSubExpr();
226 if (const CXXBindTemporaryExpr *TempExpr = dyn_cast<CXXBindTemporaryExpr>(E))
227 E = TempExpr->getSubExpr();
229 if (DiagnoseUnusedComparison(*this, E))
233 if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
234 if (E->getType()->isVoidType())
237 // If the callee has attribute pure, const, or warn_unused_result, warn with
238 // a more specific message to make it clear what is happening. If the call
239 // is written in a macro body, only warn if it has the warn_unused_result
241 if (const Decl *FD = CE->getCalleeDecl()) {
242 const FunctionDecl *Func = dyn_cast<FunctionDecl>(FD);
243 if (Func ? Func->hasUnusedResultAttr()
244 : FD->hasAttr<WarnUnusedResultAttr>()) {
245 Diag(Loc, diag::warn_unused_result) << R1 << R2;
250 if (FD->hasAttr<PureAttr>()) {
251 Diag(Loc, diag::warn_unused_call) << R1 << R2 << "pure";
254 if (FD->hasAttr<ConstAttr>()) {
255 Diag(Loc, diag::warn_unused_call) << R1 << R2 << "const";
259 } else if (ShouldSuppress)
262 if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E)) {
263 if (getLangOpts().ObjCAutoRefCount && ME->isDelegateInitCall()) {
264 Diag(Loc, diag::err_arc_unused_init_message) << R1;
267 const ObjCMethodDecl *MD = ME->getMethodDecl();
269 if (MD->hasAttr<WarnUnusedResultAttr>()) {
270 Diag(Loc, diag::warn_unused_result) << R1 << R2;
274 } else if (const PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E)) {
275 const Expr *Source = POE->getSyntacticForm();
276 if (isa<ObjCSubscriptRefExpr>(Source))
277 DiagID = diag::warn_unused_container_subscript_expr;
279 DiagID = diag::warn_unused_property_expr;
280 } else if (const CXXFunctionalCastExpr *FC
281 = dyn_cast<CXXFunctionalCastExpr>(E)) {
282 if (isa<CXXConstructExpr>(FC->getSubExpr()) ||
283 isa<CXXTemporaryObjectExpr>(FC->getSubExpr()))
286 // Diagnose "(void*) blah" as a typo for "(void) blah".
287 else if (const CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(E)) {
288 TypeSourceInfo *TI = CE->getTypeInfoAsWritten();
289 QualType T = TI->getType();
291 // We really do want to use the non-canonical type here.
292 if (T == Context.VoidPtrTy) {
293 PointerTypeLoc TL = TI->getTypeLoc().castAs<PointerTypeLoc>();
295 Diag(Loc, diag::warn_unused_voidptr)
296 << FixItHint::CreateRemoval(TL.getStarLoc());
301 if (E->isGLValue() && E->getType().isVolatileQualified()) {
302 Diag(Loc, diag::warn_unused_volatile) << R1 << R2;
306 DiagRuntimeBehavior(Loc, nullptr, PDiag(DiagID) << R1 << R2);
309 void Sema::ActOnStartOfCompoundStmt() {
313 void Sema::ActOnFinishOfCompoundStmt() {
317 sema::CompoundScopeInfo &Sema::getCurCompoundScope() const {
318 return getCurFunction()->CompoundScopes.back();
321 StmtResult Sema::ActOnCompoundStmt(SourceLocation L, SourceLocation R,
322 ArrayRef<Stmt *> Elts, bool isStmtExpr) {
323 const unsigned NumElts = Elts.size();
325 // If we're in C89 mode, check that we don't have any decls after stmts. If
326 // so, emit an extension diagnostic.
327 if (!getLangOpts().C99 && !getLangOpts().CPlusPlus) {
328 // Note that __extension__ can be around a decl.
330 // Skip over all declarations.
331 for (; i != NumElts && isa<DeclStmt>(Elts[i]); ++i)
334 // We found the end of the list or a statement. Scan for another declstmt.
335 for (; i != NumElts && !isa<DeclStmt>(Elts[i]); ++i)
339 Decl *D = *cast<DeclStmt>(Elts[i])->decl_begin();
340 Diag(D->getLocation(), diag::ext_mixed_decls_code);
343 // Warn about unused expressions in statements.
344 for (unsigned i = 0; i != NumElts; ++i) {
345 // Ignore statements that are last in a statement expression.
346 if (isStmtExpr && i == NumElts - 1)
349 DiagnoseUnusedExprResult(Elts[i]);
352 // Check for suspicious empty body (null statement) in `for' and `while'
353 // statements. Don't do anything for template instantiations, this just adds
355 if (NumElts != 0 && !CurrentInstantiationScope &&
356 getCurCompoundScope().HasEmptyLoopBodies) {
357 for (unsigned i = 0; i != NumElts - 1; ++i)
358 DiagnoseEmptyLoopBody(Elts[i], Elts[i + 1]);
361 return new (Context) CompoundStmt(Context, Elts, L, R);
365 Sema::ActOnCaseStmt(SourceLocation CaseLoc, Expr *LHSVal,
366 SourceLocation DotDotDotLoc, Expr *RHSVal,
367 SourceLocation ColonLoc) {
368 assert(LHSVal && "missing expression in case statement");
370 if (getCurFunction()->SwitchStack.empty()) {
371 Diag(CaseLoc, diag::err_case_not_in_switch);
376 CorrectDelayedTyposInExpr(LHSVal, [this](class Expr *E) {
377 if (!getLangOpts().CPlusPlus11)
378 return VerifyIntegerConstantExpression(E);
380 getCurFunction()->SwitchStack.back()->getCond()) {
381 QualType CondType = CondExpr->getType();
382 llvm::APSInt TempVal;
383 return CheckConvertedConstantExpression(E, CondType, TempVal,
392 if (!getLangOpts().CPlusPlus11) {
393 // C99 6.8.4.2p3: The expression shall be an integer constant.
394 // However, GCC allows any evaluatable integer expression.
395 if (!LHSVal->isTypeDependent() && !LHSVal->isValueDependent()) {
396 LHSVal = VerifyIntegerConstantExpression(LHSVal).get();
401 // GCC extension: The expression shall be an integer constant.
403 if (RHSVal && !RHSVal->isTypeDependent() && !RHSVal->isValueDependent()) {
404 RHSVal = VerifyIntegerConstantExpression(RHSVal).get();
405 // Recover from an error by just forgetting about it.
409 LHS = ActOnFinishFullExpr(LHSVal, LHSVal->getExprLoc(), false,
410 getLangOpts().CPlusPlus11);
414 auto RHS = RHSVal ? ActOnFinishFullExpr(RHSVal, RHSVal->getExprLoc(), false,
415 getLangOpts().CPlusPlus11)
420 CaseStmt *CS = new (Context)
421 CaseStmt(LHS.get(), RHS.get(), CaseLoc, DotDotDotLoc, ColonLoc);
422 getCurFunction()->SwitchStack.back()->addSwitchCase(CS);
426 /// ActOnCaseStmtBody - This installs a statement as the body of a case.
427 void Sema::ActOnCaseStmtBody(Stmt *caseStmt, Stmt *SubStmt) {
428 DiagnoseUnusedExprResult(SubStmt);
430 CaseStmt *CS = static_cast<CaseStmt*>(caseStmt);
431 CS->setSubStmt(SubStmt);
435 Sema::ActOnDefaultStmt(SourceLocation DefaultLoc, SourceLocation ColonLoc,
436 Stmt *SubStmt, Scope *CurScope) {
437 DiagnoseUnusedExprResult(SubStmt);
439 if (getCurFunction()->SwitchStack.empty()) {
440 Diag(DefaultLoc, diag::err_default_not_in_switch);
444 DefaultStmt *DS = new (Context) DefaultStmt(DefaultLoc, ColonLoc, SubStmt);
445 getCurFunction()->SwitchStack.back()->addSwitchCase(DS);
450 Sema::ActOnLabelStmt(SourceLocation IdentLoc, LabelDecl *TheDecl,
451 SourceLocation ColonLoc, Stmt *SubStmt) {
452 // If the label was multiply defined, reject it now.
453 if (TheDecl->getStmt()) {
454 Diag(IdentLoc, diag::err_redefinition_of_label) << TheDecl->getDeclName();
455 Diag(TheDecl->getLocation(), diag::note_previous_definition);
459 // Otherwise, things are good. Fill in the declaration and return it.
460 LabelStmt *LS = new (Context) LabelStmt(IdentLoc, TheDecl, SubStmt);
461 TheDecl->setStmt(LS);
462 if (!TheDecl->isGnuLocal()) {
463 TheDecl->setLocStart(IdentLoc);
464 if (!TheDecl->isMSAsmLabel()) {
465 // Don't update the location of MS ASM labels. These will result in
466 // a diagnostic, and changing the location here will mess that up.
467 TheDecl->setLocation(IdentLoc);
473 StmtResult Sema::ActOnAttributedStmt(SourceLocation AttrLoc,
474 ArrayRef<const Attr*> Attrs,
476 // Fill in the declaration and return it.
477 AttributedStmt *LS = AttributedStmt::Create(Context, AttrLoc, Attrs, SubStmt);
482 Sema::ActOnIfStmt(SourceLocation IfLoc, FullExprArg CondVal, Decl *CondVar,
483 Stmt *thenStmt, SourceLocation ElseLoc,
485 // If the condition was invalid, discard the if statement. We could recover
486 // better by replacing it with a valid expr, but don't do that yet.
487 if (!CondVal.get() && !CondVar) {
488 getCurFunction()->setHasDroppedStmt();
492 ExprResult CondResult(CondVal.release());
494 VarDecl *ConditionVar = nullptr;
496 ConditionVar = cast<VarDecl>(CondVar);
497 CondResult = CheckConditionVariable(ConditionVar, IfLoc, true);
498 if (CondResult.isInvalid())
501 Expr *ConditionExpr = CondResult.getAs<Expr>();
505 DiagnoseUnusedExprResult(thenStmt);
508 DiagnoseEmptyStmtBody(ConditionExpr->getLocEnd(), thenStmt,
509 diag::warn_empty_if_body);
512 DiagnoseUnusedExprResult(elseStmt);
514 return new (Context) IfStmt(Context, IfLoc, ConditionVar, ConditionExpr,
515 thenStmt, ElseLoc, elseStmt);
519 struct CaseCompareFunctor {
520 bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS,
521 const llvm::APSInt &RHS) {
522 return LHS.first < RHS;
524 bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS,
525 const std::pair<llvm::APSInt, CaseStmt*> &RHS) {
526 return LHS.first < RHS.first;
528 bool operator()(const llvm::APSInt &LHS,
529 const std::pair<llvm::APSInt, CaseStmt*> &RHS) {
530 return LHS < RHS.first;
535 /// CmpCaseVals - Comparison predicate for sorting case values.
537 static bool CmpCaseVals(const std::pair<llvm::APSInt, CaseStmt*>& lhs,
538 const std::pair<llvm::APSInt, CaseStmt*>& rhs) {
539 if (lhs.first < rhs.first)
542 if (lhs.first == rhs.first &&
543 lhs.second->getCaseLoc().getRawEncoding()
544 < rhs.second->getCaseLoc().getRawEncoding())
549 /// CmpEnumVals - Comparison predicate for sorting enumeration values.
551 static bool CmpEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs,
552 const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs)
554 return lhs.first < rhs.first;
557 /// EqEnumVals - Comparison preficate for uniqing enumeration values.
559 static bool EqEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs,
560 const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs)
562 return lhs.first == rhs.first;
565 /// GetTypeBeforeIntegralPromotion - Returns the pre-promotion type of
566 /// potentially integral-promoted expression @p expr.
567 static QualType GetTypeBeforeIntegralPromotion(Expr *&expr) {
568 if (ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(expr))
569 expr = cleanups->getSubExpr();
570 while (ImplicitCastExpr *impcast = dyn_cast<ImplicitCastExpr>(expr)) {
571 if (impcast->getCastKind() != CK_IntegralCast) break;
572 expr = impcast->getSubExpr();
574 return expr->getType();
578 Sema::ActOnStartOfSwitchStmt(SourceLocation SwitchLoc, Expr *Cond,
580 ExprResult CondResult;
582 VarDecl *ConditionVar = nullptr;
584 ConditionVar = cast<VarDecl>(CondVar);
585 CondResult = CheckConditionVariable(ConditionVar, SourceLocation(), false);
586 if (CondResult.isInvalid())
589 Cond = CondResult.get();
595 class SwitchConvertDiagnoser : public ICEConvertDiagnoser {
599 SwitchConvertDiagnoser(Expr *Cond)
600 : ICEConvertDiagnoser(/*AllowScopedEnumerations*/true, false, true),
603 SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
604 QualType T) override {
605 return S.Diag(Loc, diag::err_typecheck_statement_requires_integer) << T;
608 SemaDiagnosticBuilder diagnoseIncomplete(
609 Sema &S, SourceLocation Loc, QualType T) override {
610 return S.Diag(Loc, diag::err_switch_incomplete_class_type)
611 << T << Cond->getSourceRange();
614 SemaDiagnosticBuilder diagnoseExplicitConv(
615 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
616 return S.Diag(Loc, diag::err_switch_explicit_conversion) << T << ConvTy;
619 SemaDiagnosticBuilder noteExplicitConv(
620 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
621 return S.Diag(Conv->getLocation(), diag::note_switch_conversion)
622 << ConvTy->isEnumeralType() << ConvTy;
625 SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
626 QualType T) override {
627 return S.Diag(Loc, diag::err_switch_multiple_conversions) << T;
630 SemaDiagnosticBuilder noteAmbiguous(
631 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
632 return S.Diag(Conv->getLocation(), diag::note_switch_conversion)
633 << ConvTy->isEnumeralType() << ConvTy;
636 SemaDiagnosticBuilder diagnoseConversion(
637 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
638 llvm_unreachable("conversion functions are permitted");
640 } SwitchDiagnoser(Cond);
643 PerformContextualImplicitConversion(SwitchLoc, Cond, SwitchDiagnoser);
644 if (CondResult.isInvalid()) return StmtError();
645 Cond = CondResult.get();
647 // C99 6.8.4.2p5 - Integer promotions are performed on the controlling expr.
648 CondResult = UsualUnaryConversions(Cond);
649 if (CondResult.isInvalid()) return StmtError();
650 Cond = CondResult.get();
653 CondResult = ActOnFinishFullExpr(Cond, SwitchLoc);
654 if (CondResult.isInvalid())
656 Cond = CondResult.get();
659 getCurFunction()->setHasBranchIntoScope();
661 SwitchStmt *SS = new (Context) SwitchStmt(Context, ConditionVar, Cond);
662 getCurFunction()->SwitchStack.push_back(SS);
666 static void AdjustAPSInt(llvm::APSInt &Val, unsigned BitWidth, bool IsSigned) {
667 Val = Val.extOrTrunc(BitWidth);
668 Val.setIsSigned(IsSigned);
671 /// Check the specified case value is in range for the given unpromoted switch
673 static void checkCaseValue(Sema &S, SourceLocation Loc, const llvm::APSInt &Val,
674 unsigned UnpromotedWidth, bool UnpromotedSign) {
675 // If the case value was signed and negative and the switch expression is
676 // unsigned, don't bother to warn: this is implementation-defined behavior.
677 // FIXME: Introduce a second, default-ignored warning for this case?
678 if (UnpromotedWidth < Val.getBitWidth()) {
679 llvm::APSInt ConvVal(Val);
680 AdjustAPSInt(ConvVal, UnpromotedWidth, UnpromotedSign);
681 AdjustAPSInt(ConvVal, Val.getBitWidth(), Val.isSigned());
682 // FIXME: Use different diagnostics for overflow in conversion to promoted
683 // type versus "switch expression cannot have this value". Use proper
684 // IntRange checking rather than just looking at the unpromoted type here.
686 S.Diag(Loc, diag::warn_case_value_overflow) << Val.toString(10)
687 << ConvVal.toString(10);
691 typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl*>, 64> EnumValsTy;
693 /// Returns true if we should emit a diagnostic about this case expression not
694 /// being a part of the enum used in the switch controlling expression.
695 static bool ShouldDiagnoseSwitchCaseNotInEnum(const Sema &S,
697 const Expr *CaseExpr,
698 EnumValsTy::iterator &EI,
699 EnumValsTy::iterator &EIEnd,
700 const llvm::APSInt &Val) {
701 bool FlagType = ED->hasAttr<FlagEnumAttr>();
703 if (const DeclRefExpr *DRE =
704 dyn_cast<DeclRefExpr>(CaseExpr->IgnoreParenImpCasts())) {
705 if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) {
706 QualType VarType = VD->getType();
707 QualType EnumType = S.Context.getTypeDeclType(ED);
708 if (VD->hasGlobalStorage() && VarType.isConstQualified() &&
709 S.Context.hasSameUnqualifiedType(EnumType, VarType))
715 return !S.IsValueInFlagEnum(ED, Val, false);
717 while (EI != EIEnd && EI->first < Val)
720 if (EI != EIEnd && EI->first == Val)
728 Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, Stmt *Switch,
730 SwitchStmt *SS = cast<SwitchStmt>(Switch);
731 assert(SS == getCurFunction()->SwitchStack.back() &&
732 "switch stack missing push/pop!");
734 getCurFunction()->SwitchStack.pop_back();
736 if (!BodyStmt) return StmtError();
737 SS->setBody(BodyStmt, SwitchLoc);
739 Expr *CondExpr = SS->getCond();
740 if (!CondExpr) return StmtError();
742 QualType CondType = CondExpr->getType();
744 Expr *CondExprBeforePromotion = CondExpr;
745 QualType CondTypeBeforePromotion =
746 GetTypeBeforeIntegralPromotion(CondExprBeforePromotion);
749 // Integral promotions are performed (on the switch condition).
751 // A case value unrepresentable by the original switch condition
752 // type (before the promotion) doesn't make sense, even when it can
753 // be represented by the promoted type. Therefore we need to find
754 // the pre-promotion type of the switch condition.
755 if (!CondExpr->isTypeDependent()) {
756 // We have already converted the expression to an integral or enumeration
757 // type, when we started the switch statement. If we don't have an
758 // appropriate type now, just return an error.
759 if (!CondType->isIntegralOrEnumerationType())
762 if (CondExpr->isKnownToHaveBooleanValue()) {
763 // switch(bool_expr) {...} is often a programmer error, e.g.
764 // switch(n && mask) { ... } // Doh - should be "n & mask".
765 // One can always use an if statement instead of switch(bool_expr).
766 Diag(SwitchLoc, diag::warn_bool_switch_condition)
767 << CondExpr->getSourceRange();
771 // Get the bitwidth of the switched-on value after promotions. We must
772 // convert the integer case values to this width before comparison.
773 bool HasDependentValue
774 = CondExpr->isTypeDependent() || CondExpr->isValueDependent();
775 unsigned CondWidth = HasDependentValue ? 0 : Context.getIntWidth(CondType);
776 bool CondIsSigned = CondType->isSignedIntegerOrEnumerationType();
778 // Get the width and signedness that the condition might actually have, for
780 // FIXME: Grab an IntRange for the condition rather than using the unpromoted
782 unsigned CondWidthBeforePromotion
783 = HasDependentValue ? 0 : Context.getIntWidth(CondTypeBeforePromotion);
784 bool CondIsSignedBeforePromotion
785 = CondTypeBeforePromotion->isSignedIntegerOrEnumerationType();
787 // Accumulate all of the case values in a vector so that we can sort them
788 // and detect duplicates. This vector contains the APInt for the case after
789 // it has been converted to the condition type.
790 typedef SmallVector<std::pair<llvm::APSInt, CaseStmt*>, 64> CaseValsTy;
793 // Keep track of any GNU case ranges we see. The APSInt is the low value.
794 typedef std::vector<std::pair<llvm::APSInt, CaseStmt*> > CaseRangesTy;
795 CaseRangesTy CaseRanges;
797 DefaultStmt *TheDefaultStmt = nullptr;
799 bool CaseListIsErroneous = false;
801 for (SwitchCase *SC = SS->getSwitchCaseList(); SC && !HasDependentValue;
802 SC = SC->getNextSwitchCase()) {
804 if (DefaultStmt *DS = dyn_cast<DefaultStmt>(SC)) {
805 if (TheDefaultStmt) {
806 Diag(DS->getDefaultLoc(), diag::err_multiple_default_labels_defined);
807 Diag(TheDefaultStmt->getDefaultLoc(), diag::note_duplicate_case_prev);
809 // FIXME: Remove the default statement from the switch block so that
810 // we'll return a valid AST. This requires recursing down the AST and
811 // finding it, not something we are set up to do right now. For now,
812 // just lop the entire switch stmt out of the AST.
813 CaseListIsErroneous = true;
818 CaseStmt *CS = cast<CaseStmt>(SC);
820 Expr *Lo = CS->getLHS();
822 if (Lo->isTypeDependent() || Lo->isValueDependent()) {
823 HasDependentValue = true;
829 if (getLangOpts().CPlusPlus11) {
830 // C++11 [stmt.switch]p2: the constant-expression shall be a converted
831 // constant expression of the promoted type of the switch condition.
833 CheckConvertedConstantExpression(Lo, CondType, LoVal, CCEK_CaseValue);
834 if (ConvLo.isInvalid()) {
835 CaseListIsErroneous = true;
840 // We already verified that the expression has a i-c-e value (C99
841 // 6.8.4.2p3) - get that value now.
842 LoVal = Lo->EvaluateKnownConstInt(Context);
844 // If the LHS is not the same type as the condition, insert an implicit
846 Lo = DefaultLvalueConversion(Lo).get();
847 Lo = ImpCastExprToType(Lo, CondType, CK_IntegralCast).get();
850 // Check the unconverted value is within the range of possible values of
851 // the switch expression.
852 checkCaseValue(*this, Lo->getLocStart(), LoVal,
853 CondWidthBeforePromotion, CondIsSignedBeforePromotion);
855 // Convert the value to the same width/sign as the condition.
856 AdjustAPSInt(LoVal, CondWidth, CondIsSigned);
860 // If this is a case range, remember it in CaseRanges, otherwise CaseVals.
862 if (CS->getRHS()->isTypeDependent() ||
863 CS->getRHS()->isValueDependent()) {
864 HasDependentValue = true;
867 CaseRanges.push_back(std::make_pair(LoVal, CS));
869 CaseVals.push_back(std::make_pair(LoVal, CS));
873 if (!HasDependentValue) {
874 // If we don't have a default statement, check whether the
875 // condition is constant.
876 llvm::APSInt ConstantCondValue;
877 bool HasConstantCond = false;
878 if (!HasDependentValue && !TheDefaultStmt) {
879 HasConstantCond = CondExpr->EvaluateAsInt(ConstantCondValue, Context,
880 Expr::SE_AllowSideEffects);
881 assert(!HasConstantCond ||
882 (ConstantCondValue.getBitWidth() == CondWidth &&
883 ConstantCondValue.isSigned() == CondIsSigned));
885 bool ShouldCheckConstantCond = HasConstantCond;
887 // Sort all the scalar case values so we can easily detect duplicates.
888 std::stable_sort(CaseVals.begin(), CaseVals.end(), CmpCaseVals);
890 if (!CaseVals.empty()) {
891 for (unsigned i = 0, e = CaseVals.size(); i != e; ++i) {
892 if (ShouldCheckConstantCond &&
893 CaseVals[i].first == ConstantCondValue)
894 ShouldCheckConstantCond = false;
896 if (i != 0 && CaseVals[i].first == CaseVals[i-1].first) {
897 // If we have a duplicate, report it.
898 // First, determine if either case value has a name
899 StringRef PrevString, CurrString;
900 Expr *PrevCase = CaseVals[i-1].second->getLHS()->IgnoreParenCasts();
901 Expr *CurrCase = CaseVals[i].second->getLHS()->IgnoreParenCasts();
902 if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(PrevCase)) {
903 PrevString = DeclRef->getDecl()->getName();
905 if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(CurrCase)) {
906 CurrString = DeclRef->getDecl()->getName();
908 SmallString<16> CaseValStr;
909 CaseVals[i-1].first.toString(CaseValStr);
911 if (PrevString == CurrString)
912 Diag(CaseVals[i].second->getLHS()->getLocStart(),
913 diag::err_duplicate_case) <<
914 (PrevString.empty() ? StringRef(CaseValStr) : PrevString);
916 Diag(CaseVals[i].second->getLHS()->getLocStart(),
917 diag::err_duplicate_case_differing_expr) <<
918 (PrevString.empty() ? StringRef(CaseValStr) : PrevString) <<
919 (CurrString.empty() ? StringRef(CaseValStr) : CurrString) <<
922 Diag(CaseVals[i-1].second->getLHS()->getLocStart(),
923 diag::note_duplicate_case_prev);
924 // FIXME: We really want to remove the bogus case stmt from the
925 // substmt, but we have no way to do this right now.
926 CaseListIsErroneous = true;
931 // Detect duplicate case ranges, which usually don't exist at all in
933 if (!CaseRanges.empty()) {
934 // Sort all the case ranges by their low value so we can easily detect
935 // overlaps between ranges.
936 std::stable_sort(CaseRanges.begin(), CaseRanges.end());
938 // Scan the ranges, computing the high values and removing empty ranges.
939 std::vector<llvm::APSInt> HiVals;
940 for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) {
941 llvm::APSInt &LoVal = CaseRanges[i].first;
942 CaseStmt *CR = CaseRanges[i].second;
943 Expr *Hi = CR->getRHS();
946 if (getLangOpts().CPlusPlus11) {
947 // C++11 [stmt.switch]p2: the constant-expression shall be a converted
948 // constant expression of the promoted type of the switch condition.
950 CheckConvertedConstantExpression(Hi, CondType, HiVal,
952 if (ConvHi.isInvalid()) {
953 CaseListIsErroneous = true;
958 HiVal = Hi->EvaluateKnownConstInt(Context);
960 // If the RHS is not the same type as the condition, insert an
962 Hi = DefaultLvalueConversion(Hi).get();
963 Hi = ImpCastExprToType(Hi, CondType, CK_IntegralCast).get();
966 // Check the unconverted value is within the range of possible values of
967 // the switch expression.
968 checkCaseValue(*this, Hi->getLocStart(), HiVal,
969 CondWidthBeforePromotion, CondIsSignedBeforePromotion);
971 // Convert the value to the same width/sign as the condition.
972 AdjustAPSInt(HiVal, CondWidth, CondIsSigned);
976 // If the low value is bigger than the high value, the case is empty.
978 Diag(CR->getLHS()->getLocStart(), diag::warn_case_empty_range)
979 << SourceRange(CR->getLHS()->getLocStart(),
981 CaseRanges.erase(CaseRanges.begin()+i);
986 if (ShouldCheckConstantCond &&
987 LoVal <= ConstantCondValue &&
988 ConstantCondValue <= HiVal)
989 ShouldCheckConstantCond = false;
991 HiVals.push_back(HiVal);
994 // Rescan the ranges, looking for overlap with singleton values and other
995 // ranges. Since the range list is sorted, we only need to compare case
996 // ranges with their neighbors.
997 for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) {
998 llvm::APSInt &CRLo = CaseRanges[i].first;
999 llvm::APSInt &CRHi = HiVals[i];
1000 CaseStmt *CR = CaseRanges[i].second;
1002 // Check to see whether the case range overlaps with any
1004 CaseStmt *OverlapStmt = nullptr;
1005 llvm::APSInt OverlapVal(32);
1007 // Find the smallest value >= the lower bound. If I is in the
1008 // case range, then we have overlap.
1009 CaseValsTy::iterator I = std::lower_bound(CaseVals.begin(),
1010 CaseVals.end(), CRLo,
1011 CaseCompareFunctor());
1012 if (I != CaseVals.end() && I->first < CRHi) {
1013 OverlapVal = I->first; // Found overlap with scalar.
1014 OverlapStmt = I->second;
1017 // Find the smallest value bigger than the upper bound.
1018 I = std::upper_bound(I, CaseVals.end(), CRHi, CaseCompareFunctor());
1019 if (I != CaseVals.begin() && (I-1)->first >= CRLo) {
1020 OverlapVal = (I-1)->first; // Found overlap with scalar.
1021 OverlapStmt = (I-1)->second;
1024 // Check to see if this case stmt overlaps with the subsequent
1026 if (i && CRLo <= HiVals[i-1]) {
1027 OverlapVal = HiVals[i-1]; // Found overlap with range.
1028 OverlapStmt = CaseRanges[i-1].second;
1032 // If we have a duplicate, report it.
1033 Diag(CR->getLHS()->getLocStart(), diag::err_duplicate_case)
1034 << OverlapVal.toString(10);
1035 Diag(OverlapStmt->getLHS()->getLocStart(),
1036 diag::note_duplicate_case_prev);
1037 // FIXME: We really want to remove the bogus case stmt from the
1038 // substmt, but we have no way to do this right now.
1039 CaseListIsErroneous = true;
1044 // Complain if we have a constant condition and we didn't find a match.
1045 if (!CaseListIsErroneous && ShouldCheckConstantCond) {
1046 // TODO: it would be nice if we printed enums as enums, chars as
1048 Diag(CondExpr->getExprLoc(), diag::warn_missing_case_for_condition)
1049 << ConstantCondValue.toString(10)
1050 << CondExpr->getSourceRange();
1053 // Check to see if switch is over an Enum and handles all of its
1054 // values. We only issue a warning if there is not 'default:', but
1055 // we still do the analysis to preserve this information in the AST
1056 // (which can be used by flow-based analyes).
1058 const EnumType *ET = CondTypeBeforePromotion->getAs<EnumType>();
1060 // If switch has default case, then ignore it.
1061 if (!CaseListIsErroneous && !HasConstantCond && ET) {
1062 const EnumDecl *ED = ET->getDecl();
1063 EnumValsTy EnumVals;
1065 // Gather all enum values, set their type and sort them,
1066 // allowing easier comparison with CaseVals.
1067 for (auto *EDI : ED->enumerators()) {
1068 llvm::APSInt Val = EDI->getInitVal();
1069 AdjustAPSInt(Val, CondWidth, CondIsSigned);
1070 EnumVals.push_back(std::make_pair(Val, EDI));
1072 std::stable_sort(EnumVals.begin(), EnumVals.end(), CmpEnumVals);
1073 auto EI = EnumVals.begin(), EIEnd =
1074 std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals);
1076 // See which case values aren't in enum.
1077 for (CaseValsTy::const_iterator CI = CaseVals.begin();
1078 CI != CaseVals.end(); CI++) {
1079 Expr *CaseExpr = CI->second->getLHS();
1080 if (ShouldDiagnoseSwitchCaseNotInEnum(*this, ED, CaseExpr, EI, EIEnd,
1082 Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum)
1083 << CondTypeBeforePromotion;
1086 // See which of case ranges aren't in enum
1087 EI = EnumVals.begin();
1088 for (CaseRangesTy::const_iterator RI = CaseRanges.begin();
1089 RI != CaseRanges.end(); RI++) {
1090 Expr *CaseExpr = RI->second->getLHS();
1091 if (ShouldDiagnoseSwitchCaseNotInEnum(*this, ED, CaseExpr, EI, EIEnd,
1093 Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum)
1094 << CondTypeBeforePromotion;
1097 RI->second->getRHS()->EvaluateKnownConstInt(Context);
1098 AdjustAPSInt(Hi, CondWidth, CondIsSigned);
1100 CaseExpr = RI->second->getRHS();
1101 if (ShouldDiagnoseSwitchCaseNotInEnum(*this, ED, CaseExpr, EI, EIEnd,
1103 Diag(CaseExpr->getExprLoc(), diag::warn_not_in_enum)
1104 << CondTypeBeforePromotion;
1107 // Check which enum vals aren't in switch
1108 auto CI = CaseVals.begin();
1109 auto RI = CaseRanges.begin();
1110 bool hasCasesNotInSwitch = false;
1112 SmallVector<DeclarationName,8> UnhandledNames;
1114 for (EI = EnumVals.begin(); EI != EIEnd; EI++){
1115 // Drop unneeded case values
1116 while (CI != CaseVals.end() && CI->first < EI->first)
1119 if (CI != CaseVals.end() && CI->first == EI->first)
1122 // Drop unneeded case ranges
1123 for (; RI != CaseRanges.end(); RI++) {
1125 RI->second->getRHS()->EvaluateKnownConstInt(Context);
1126 AdjustAPSInt(Hi, CondWidth, CondIsSigned);
1127 if (EI->first <= Hi)
1131 if (RI == CaseRanges.end() || EI->first < RI->first) {
1132 hasCasesNotInSwitch = true;
1133 UnhandledNames.push_back(EI->second->getDeclName());
1137 if (TheDefaultStmt && UnhandledNames.empty())
1138 Diag(TheDefaultStmt->getDefaultLoc(), diag::warn_unreachable_default);
1140 // Produce a nice diagnostic if multiple values aren't handled.
1141 if (!UnhandledNames.empty()) {
1142 DiagnosticBuilder DB = Diag(CondExpr->getExprLoc(),
1143 TheDefaultStmt ? diag::warn_def_missing_case
1144 : diag::warn_missing_case)
1145 << (int)UnhandledNames.size();
1147 for (size_t I = 0, E = std::min(UnhandledNames.size(), (size_t)3);
1149 DB << UnhandledNames[I];
1152 if (!hasCasesNotInSwitch)
1153 SS->setAllEnumCasesCovered();
1158 DiagnoseEmptyStmtBody(CondExpr->getLocEnd(), BodyStmt,
1159 diag::warn_empty_switch_body);
1161 // FIXME: If the case list was broken is some way, we don't have a good system
1162 // to patch it up. Instead, just return the whole substmt as broken.
1163 if (CaseListIsErroneous)
1170 Sema::DiagnoseAssignmentEnum(QualType DstType, QualType SrcType,
1172 if (Diags.isIgnored(diag::warn_not_in_enum_assignment, SrcExpr->getExprLoc()))
1175 if (const EnumType *ET = DstType->getAs<EnumType>())
1176 if (!Context.hasSameUnqualifiedType(SrcType, DstType) &&
1177 SrcType->isIntegerType()) {
1178 if (!SrcExpr->isTypeDependent() && !SrcExpr->isValueDependent() &&
1179 SrcExpr->isIntegerConstantExpr(Context)) {
1180 // Get the bitwidth of the enum value before promotions.
1181 unsigned DstWidth = Context.getIntWidth(DstType);
1182 bool DstIsSigned = DstType->isSignedIntegerOrEnumerationType();
1184 llvm::APSInt RhsVal = SrcExpr->EvaluateKnownConstInt(Context);
1185 AdjustAPSInt(RhsVal, DstWidth, DstIsSigned);
1186 const EnumDecl *ED = ET->getDecl();
1188 if (ED->hasAttr<FlagEnumAttr>()) {
1189 if (!IsValueInFlagEnum(ED, RhsVal, true))
1190 Diag(SrcExpr->getExprLoc(), diag::warn_not_in_enum_assignment)
1191 << DstType.getUnqualifiedType();
1193 typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl *>, 64>
1195 EnumValsTy EnumVals;
1197 // Gather all enum values, set their type and sort them,
1198 // allowing easier comparison with rhs constant.
1199 for (auto *EDI : ED->enumerators()) {
1200 llvm::APSInt Val = EDI->getInitVal();
1201 AdjustAPSInt(Val, DstWidth, DstIsSigned);
1202 EnumVals.push_back(std::make_pair(Val, EDI));
1204 if (EnumVals.empty())
1206 std::stable_sort(EnumVals.begin(), EnumVals.end(), CmpEnumVals);
1207 EnumValsTy::iterator EIend =
1208 std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals);
1210 // See which values aren't in the enum.
1211 EnumValsTy::const_iterator EI = EnumVals.begin();
1212 while (EI != EIend && EI->first < RhsVal)
1214 if (EI == EIend || EI->first != RhsVal) {
1215 Diag(SrcExpr->getExprLoc(), diag::warn_not_in_enum_assignment)
1216 << DstType.getUnqualifiedType();
1224 Sema::ActOnWhileStmt(SourceLocation WhileLoc, FullExprArg Cond,
1225 Decl *CondVar, Stmt *Body) {
1226 ExprResult CondResult(Cond.release());
1228 VarDecl *ConditionVar = nullptr;
1230 ConditionVar = cast<VarDecl>(CondVar);
1231 CondResult = CheckConditionVariable(ConditionVar, WhileLoc, true);
1232 if (CondResult.isInvalid())
1235 Expr *ConditionExpr = CondResult.get();
1238 CheckBreakContinueBinding(ConditionExpr);
1240 DiagnoseUnusedExprResult(Body);
1242 if (isa<NullStmt>(Body))
1243 getCurCompoundScope().setHasEmptyLoopBodies();
1245 return new (Context)
1246 WhileStmt(Context, ConditionVar, ConditionExpr, Body, WhileLoc);
1250 Sema::ActOnDoStmt(SourceLocation DoLoc, Stmt *Body,
1251 SourceLocation WhileLoc, SourceLocation CondLParen,
1252 Expr *Cond, SourceLocation CondRParen) {
1253 assert(Cond && "ActOnDoStmt(): missing expression");
1255 CheckBreakContinueBinding(Cond);
1256 ExprResult CondResult = CheckBooleanCondition(Cond, DoLoc);
1257 if (CondResult.isInvalid())
1259 Cond = CondResult.get();
1261 CondResult = ActOnFinishFullExpr(Cond, DoLoc);
1262 if (CondResult.isInvalid())
1264 Cond = CondResult.get();
1266 DiagnoseUnusedExprResult(Body);
1268 return new (Context) DoStmt(Body, Cond, DoLoc, WhileLoc, CondRParen);
1272 // This visitor will traverse a conditional statement and store all
1273 // the evaluated decls into a vector. Simple is set to true if none
1274 // of the excluded constructs are used.
1275 class DeclExtractor : public EvaluatedExprVisitor<DeclExtractor> {
1276 llvm::SmallPtrSetImpl<VarDecl*> &Decls;
1277 SmallVectorImpl<SourceRange> &Ranges;
1280 typedef EvaluatedExprVisitor<DeclExtractor> Inherited;
1282 DeclExtractor(Sema &S, llvm::SmallPtrSetImpl<VarDecl*> &Decls,
1283 SmallVectorImpl<SourceRange> &Ranges) :
1284 Inherited(S.Context),
1289 bool isSimple() { return Simple; }
1291 // Replaces the method in EvaluatedExprVisitor.
1292 void VisitMemberExpr(MemberExpr* E) {
1296 // Any Stmt not whitelisted will cause the condition to be marked complex.
1297 void VisitStmt(Stmt *S) {
1301 void VisitBinaryOperator(BinaryOperator *E) {
1306 void VisitCastExpr(CastExpr *E) {
1307 Visit(E->getSubExpr());
1310 void VisitUnaryOperator(UnaryOperator *E) {
1311 // Skip checking conditionals with derefernces.
1312 if (E->getOpcode() == UO_Deref)
1315 Visit(E->getSubExpr());
1318 void VisitConditionalOperator(ConditionalOperator *E) {
1319 Visit(E->getCond());
1320 Visit(E->getTrueExpr());
1321 Visit(E->getFalseExpr());
1324 void VisitParenExpr(ParenExpr *E) {
1325 Visit(E->getSubExpr());
1328 void VisitBinaryConditionalOperator(BinaryConditionalOperator *E) {
1329 Visit(E->getOpaqueValue()->getSourceExpr());
1330 Visit(E->getFalseExpr());
1333 void VisitIntegerLiteral(IntegerLiteral *E) { }
1334 void VisitFloatingLiteral(FloatingLiteral *E) { }
1335 void VisitCXXBoolLiteralExpr(CXXBoolLiteralExpr *E) { }
1336 void VisitCharacterLiteral(CharacterLiteral *E) { }
1337 void VisitGNUNullExpr(GNUNullExpr *E) { }
1338 void VisitImaginaryLiteral(ImaginaryLiteral *E) { }
1340 void VisitDeclRefExpr(DeclRefExpr *E) {
1341 VarDecl *VD = dyn_cast<VarDecl>(E->getDecl());
1344 Ranges.push_back(E->getSourceRange());
1349 }; // end class DeclExtractor
1351 // DeclMatcher checks to see if the decls are used in a non-evauluated
1353 class DeclMatcher : public EvaluatedExprVisitor<DeclMatcher> {
1354 llvm::SmallPtrSetImpl<VarDecl*> &Decls;
1358 typedef EvaluatedExprVisitor<DeclMatcher> Inherited;
1360 DeclMatcher(Sema &S, llvm::SmallPtrSetImpl<VarDecl*> &Decls,
1362 Inherited(S.Context), Decls(Decls), FoundDecl(false) {
1363 if (!Statement) return;
1368 void VisitReturnStmt(ReturnStmt *S) {
1372 void VisitBreakStmt(BreakStmt *S) {
1376 void VisitGotoStmt(GotoStmt *S) {
1380 void VisitCastExpr(CastExpr *E) {
1381 if (E->getCastKind() == CK_LValueToRValue)
1382 CheckLValueToRValueCast(E->getSubExpr());
1384 Visit(E->getSubExpr());
1387 void CheckLValueToRValueCast(Expr *E) {
1388 E = E->IgnoreParenImpCasts();
1390 if (isa<DeclRefExpr>(E)) {
1394 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
1395 Visit(CO->getCond());
1396 CheckLValueToRValueCast(CO->getTrueExpr());
1397 CheckLValueToRValueCast(CO->getFalseExpr());
1401 if (BinaryConditionalOperator *BCO =
1402 dyn_cast<BinaryConditionalOperator>(E)) {
1403 CheckLValueToRValueCast(BCO->getOpaqueValue()->getSourceExpr());
1404 CheckLValueToRValueCast(BCO->getFalseExpr());
1411 void VisitDeclRefExpr(DeclRefExpr *E) {
1412 if (VarDecl *VD = dyn_cast<VarDecl>(E->getDecl()))
1413 if (Decls.count(VD))
1417 bool FoundDeclInUse() { return FoundDecl; }
1419 }; // end class DeclMatcher
1421 void CheckForLoopConditionalStatement(Sema &S, Expr *Second,
1422 Expr *Third, Stmt *Body) {
1423 // Condition is empty
1424 if (!Second) return;
1426 if (S.Diags.isIgnored(diag::warn_variables_not_in_loop_body,
1427 Second->getLocStart()))
1430 PartialDiagnostic PDiag = S.PDiag(diag::warn_variables_not_in_loop_body);
1431 llvm::SmallPtrSet<VarDecl*, 8> Decls;
1432 SmallVector<SourceRange, 10> Ranges;
1433 DeclExtractor DE(S, Decls, Ranges);
1436 // Don't analyze complex conditionals.
1437 if (!DE.isSimple()) return;
1440 if (Decls.size() == 0) return;
1442 // Don't warn on volatile, static, or global variables.
1443 for (llvm::SmallPtrSetImpl<VarDecl*>::iterator I = Decls.begin(),
1446 if ((*I)->getType().isVolatileQualified() ||
1447 (*I)->hasGlobalStorage()) return;
1449 if (DeclMatcher(S, Decls, Second).FoundDeclInUse() ||
1450 DeclMatcher(S, Decls, Third).FoundDeclInUse() ||
1451 DeclMatcher(S, Decls, Body).FoundDeclInUse())
1454 // Load decl names into diagnostic.
1455 if (Decls.size() > 4)
1458 PDiag << Decls.size();
1459 for (llvm::SmallPtrSetImpl<VarDecl*>::iterator I = Decls.begin(),
1462 PDiag << (*I)->getDeclName();
1465 // Load SourceRanges into diagnostic if there is room.
1466 // Otherwise, load the SourceRange of the conditional expression.
1467 if (Ranges.size() <= PartialDiagnostic::MaxArguments)
1468 for (SmallVectorImpl<SourceRange>::iterator I = Ranges.begin(),
1473 PDiag << Second->getSourceRange();
1475 S.Diag(Ranges.begin()->getBegin(), PDiag);
1478 // If Statement is an incemement or decrement, return true and sets the
1479 // variables Increment and DRE.
1480 bool ProcessIterationStmt(Sema &S, Stmt* Statement, bool &Increment,
1481 DeclRefExpr *&DRE) {
1482 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(Statement)) {
1483 switch (UO->getOpcode()) {
1484 default: return false;
1494 DRE = dyn_cast<DeclRefExpr>(UO->getSubExpr());
1498 if (CXXOperatorCallExpr *Call = dyn_cast<CXXOperatorCallExpr>(Statement)) {
1499 FunctionDecl *FD = Call->getDirectCallee();
1500 if (!FD || !FD->isOverloadedOperator()) return false;
1501 switch (FD->getOverloadedOperator()) {
1502 default: return false;
1510 DRE = dyn_cast<DeclRefExpr>(Call->getArg(0));
1517 // A visitor to determine if a continue or break statement is a
1519 class BreakContinueFinder : public EvaluatedExprVisitor<BreakContinueFinder> {
1520 SourceLocation BreakLoc;
1521 SourceLocation ContinueLoc;
1523 BreakContinueFinder(Sema &S, Stmt* Body) :
1524 Inherited(S.Context) {
1528 typedef EvaluatedExprVisitor<BreakContinueFinder> Inherited;
1530 void VisitContinueStmt(ContinueStmt* E) {
1531 ContinueLoc = E->getContinueLoc();
1534 void VisitBreakStmt(BreakStmt* E) {
1535 BreakLoc = E->getBreakLoc();
1538 bool ContinueFound() { return ContinueLoc.isValid(); }
1539 bool BreakFound() { return BreakLoc.isValid(); }
1540 SourceLocation GetContinueLoc() { return ContinueLoc; }
1541 SourceLocation GetBreakLoc() { return BreakLoc; }
1543 }; // end class BreakContinueFinder
1545 // Emit a warning when a loop increment/decrement appears twice per loop
1546 // iteration. The conditions which trigger this warning are:
1547 // 1) The last statement in the loop body and the third expression in the
1548 // for loop are both increment or both decrement of the same variable
1549 // 2) No continue statements in the loop body.
1550 void CheckForRedundantIteration(Sema &S, Expr *Third, Stmt *Body) {
1551 // Return when there is nothing to check.
1552 if (!Body || !Third) return;
1554 if (S.Diags.isIgnored(diag::warn_redundant_loop_iteration,
1555 Third->getLocStart()))
1558 // Get the last statement from the loop body.
1559 CompoundStmt *CS = dyn_cast<CompoundStmt>(Body);
1560 if (!CS || CS->body_empty()) return;
1561 Stmt *LastStmt = CS->body_back();
1562 if (!LastStmt) return;
1564 bool LoopIncrement, LastIncrement;
1565 DeclRefExpr *LoopDRE, *LastDRE;
1567 if (!ProcessIterationStmt(S, Third, LoopIncrement, LoopDRE)) return;
1568 if (!ProcessIterationStmt(S, LastStmt, LastIncrement, LastDRE)) return;
1570 // Check that the two statements are both increments or both decrements
1571 // on the same variable.
1572 if (LoopIncrement != LastIncrement ||
1573 LoopDRE->getDecl() != LastDRE->getDecl()) return;
1575 if (BreakContinueFinder(S, Body).ContinueFound()) return;
1577 S.Diag(LastDRE->getLocation(), diag::warn_redundant_loop_iteration)
1578 << LastDRE->getDecl() << LastIncrement;
1579 S.Diag(LoopDRE->getLocation(), diag::note_loop_iteration_here)
1586 void Sema::CheckBreakContinueBinding(Expr *E) {
1587 if (!E || getLangOpts().CPlusPlus)
1589 BreakContinueFinder BCFinder(*this, E);
1590 Scope *BreakParent = CurScope->getBreakParent();
1591 if (BCFinder.BreakFound() && BreakParent) {
1592 if (BreakParent->getFlags() & Scope::SwitchScope) {
1593 Diag(BCFinder.GetBreakLoc(), diag::warn_break_binds_to_switch);
1595 Diag(BCFinder.GetBreakLoc(), diag::warn_loop_ctrl_binds_to_inner)
1598 } else if (BCFinder.ContinueFound() && CurScope->getContinueParent()) {
1599 Diag(BCFinder.GetContinueLoc(), diag::warn_loop_ctrl_binds_to_inner)
1605 Sema::ActOnForStmt(SourceLocation ForLoc, SourceLocation LParenLoc,
1606 Stmt *First, FullExprArg second, Decl *secondVar,
1608 SourceLocation RParenLoc, Stmt *Body) {
1609 if (!getLangOpts().CPlusPlus) {
1610 if (DeclStmt *DS = dyn_cast_or_null<DeclStmt>(First)) {
1611 // C99 6.8.5p3: The declaration part of a 'for' statement shall only
1612 // declare identifiers for objects having storage class 'auto' or
1614 for (auto *DI : DS->decls()) {
1615 VarDecl *VD = dyn_cast<VarDecl>(DI);
1616 if (VD && VD->isLocalVarDecl() && !VD->hasLocalStorage())
1619 Diag(DI->getLocation(), diag::err_non_local_variable_decl_in_for);
1620 DI->setInvalidDecl();
1626 CheckBreakContinueBinding(second.get());
1627 CheckBreakContinueBinding(third.get());
1629 CheckForLoopConditionalStatement(*this, second.get(), third.get(), Body);
1630 CheckForRedundantIteration(*this, third.get(), Body);
1632 ExprResult SecondResult(second.release());
1633 VarDecl *ConditionVar = nullptr;
1635 ConditionVar = cast<VarDecl>(secondVar);
1636 SecondResult = CheckConditionVariable(ConditionVar, ForLoc, true);
1637 if (SecondResult.isInvalid())
1641 Expr *Third = third.release().getAs<Expr>();
1643 DiagnoseUnusedExprResult(First);
1644 DiagnoseUnusedExprResult(Third);
1645 DiagnoseUnusedExprResult(Body);
1647 if (isa<NullStmt>(Body))
1648 getCurCompoundScope().setHasEmptyLoopBodies();
1650 return new (Context) ForStmt(Context, First, SecondResult.get(), ConditionVar,
1651 Third, Body, ForLoc, LParenLoc, RParenLoc);
1654 /// In an Objective C collection iteration statement:
1656 /// x can be an arbitrary l-value expression. Bind it up as a
1657 /// full-expression.
1658 StmtResult Sema::ActOnForEachLValueExpr(Expr *E) {
1659 // Reduce placeholder expressions here. Note that this rejects the
1660 // use of pseudo-object l-values in this position.
1661 ExprResult result = CheckPlaceholderExpr(E);
1662 if (result.isInvalid()) return StmtError();
1665 ExprResult FullExpr = ActOnFinishFullExpr(E);
1666 if (FullExpr.isInvalid())
1668 return StmtResult(static_cast<Stmt*>(FullExpr.get()));
1672 Sema::CheckObjCForCollectionOperand(SourceLocation forLoc, Expr *collection) {
1676 ExprResult result = CorrectDelayedTyposInExpr(collection);
1677 if (!result.isUsable())
1679 collection = result.get();
1681 // Bail out early if we've got a type-dependent expression.
1682 if (collection->isTypeDependent()) return collection;
1684 // Perform normal l-value conversion.
1685 result = DefaultFunctionArrayLvalueConversion(collection);
1686 if (result.isInvalid())
1688 collection = result.get();
1690 // The operand needs to have object-pointer type.
1691 // TODO: should we do a contextual conversion?
1692 const ObjCObjectPointerType *pointerType =
1693 collection->getType()->getAs<ObjCObjectPointerType>();
1695 return Diag(forLoc, diag::err_collection_expr_type)
1696 << collection->getType() << collection->getSourceRange();
1698 // Check that the operand provides
1699 // - countByEnumeratingWithState:objects:count:
1700 const ObjCObjectType *objectType = pointerType->getObjectType();
1701 ObjCInterfaceDecl *iface = objectType->getInterface();
1703 // If we have a forward-declared type, we can't do this check.
1704 // Under ARC, it is an error not to have a forward-declared class.
1706 RequireCompleteType(forLoc, QualType(objectType, 0),
1707 getLangOpts().ObjCAutoRefCount
1708 ? diag::err_arc_collection_forward
1711 // Otherwise, if we have any useful type information, check that
1712 // the type declares the appropriate method.
1713 } else if (iface || !objectType->qual_empty()) {
1714 IdentifierInfo *selectorIdents[] = {
1715 &Context.Idents.get("countByEnumeratingWithState"),
1716 &Context.Idents.get("objects"),
1717 &Context.Idents.get("count")
1719 Selector selector = Context.Selectors.getSelector(3, &selectorIdents[0]);
1721 ObjCMethodDecl *method = nullptr;
1723 // If there's an interface, look in both the public and private APIs.
1725 method = iface->lookupInstanceMethod(selector);
1726 if (!method) method = iface->lookupPrivateMethod(selector);
1729 // Also check protocol qualifiers.
1731 method = LookupMethodInQualifiedType(selector, pointerType,
1734 // If we didn't find it anywhere, give up.
1736 Diag(forLoc, diag::warn_collection_expr_type)
1737 << collection->getType() << selector << collection->getSourceRange();
1740 // TODO: check for an incompatible signature?
1743 // Wrap up any cleanups in the expression.
1748 Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc,
1749 Stmt *First, Expr *collection,
1750 SourceLocation RParenLoc) {
1752 ExprResult CollectionExprResult =
1753 CheckObjCForCollectionOperand(ForLoc, collection);
1757 if (DeclStmt *DS = dyn_cast<DeclStmt>(First)) {
1758 if (!DS->isSingleDecl())
1759 return StmtError(Diag((*DS->decl_begin())->getLocation(),
1760 diag::err_toomany_element_decls));
1762 VarDecl *D = dyn_cast<VarDecl>(DS->getSingleDecl());
1763 if (!D || D->isInvalidDecl())
1766 FirstType = D->getType();
1767 // C99 6.8.5p3: The declaration part of a 'for' statement shall only
1768 // declare identifiers for objects having storage class 'auto' or
1770 if (!D->hasLocalStorage())
1771 return StmtError(Diag(D->getLocation(),
1772 diag::err_non_local_variable_decl_in_for));
1774 // If the type contained 'auto', deduce the 'auto' to 'id'.
1775 if (FirstType->getContainedAutoType()) {
1776 OpaqueValueExpr OpaqueId(D->getLocation(), Context.getObjCIdType(),
1778 Expr *DeducedInit = &OpaqueId;
1779 if (DeduceAutoType(D->getTypeSourceInfo(), DeducedInit, FirstType) ==
1781 DiagnoseAutoDeductionFailure(D, DeducedInit);
1782 if (FirstType.isNull()) {
1783 D->setInvalidDecl();
1787 D->setType(FirstType);
1789 if (ActiveTemplateInstantiations.empty()) {
1790 SourceLocation Loc =
1791 D->getTypeSourceInfo()->getTypeLoc().getBeginLoc();
1792 Diag(Loc, diag::warn_auto_var_is_id)
1793 << D->getDeclName();
1798 Expr *FirstE = cast<Expr>(First);
1799 if (!FirstE->isTypeDependent() && !FirstE->isLValue())
1800 return StmtError(Diag(First->getLocStart(),
1801 diag::err_selector_element_not_lvalue)
1802 << First->getSourceRange());
1804 FirstType = static_cast<Expr*>(First)->getType();
1805 if (FirstType.isConstQualified())
1806 Diag(ForLoc, diag::err_selector_element_const_type)
1807 << FirstType << First->getSourceRange();
1809 if (!FirstType->isDependentType() &&
1810 !FirstType->isObjCObjectPointerType() &&
1811 !FirstType->isBlockPointerType())
1812 return StmtError(Diag(ForLoc, diag::err_selector_element_type)
1813 << FirstType << First->getSourceRange());
1816 if (CollectionExprResult.isInvalid())
1819 CollectionExprResult = ActOnFinishFullExpr(CollectionExprResult.get());
1820 if (CollectionExprResult.isInvalid())
1823 return new (Context) ObjCForCollectionStmt(First, CollectionExprResult.get(),
1824 nullptr, ForLoc, RParenLoc);
1827 /// Finish building a variable declaration for a for-range statement.
1828 /// \return true if an error occurs.
1829 static bool FinishForRangeVarDecl(Sema &SemaRef, VarDecl *Decl, Expr *Init,
1830 SourceLocation Loc, int DiagID) {
1831 if (Decl->getType()->isUndeducedType()) {
1832 ExprResult Res = SemaRef.CorrectDelayedTyposInExpr(Init);
1833 if (!Res.isUsable()) {
1834 Decl->setInvalidDecl();
1840 // Deduce the type for the iterator variable now rather than leaving it to
1841 // AddInitializerToDecl, so we can produce a more suitable diagnostic.
1843 if ((!isa<InitListExpr>(Init) && Init->getType()->isVoidType()) ||
1844 SemaRef.DeduceAutoType(Decl->getTypeSourceInfo(), Init, InitType) ==
1846 SemaRef.Diag(Loc, DiagID) << Init->getType();
1847 if (InitType.isNull()) {
1848 Decl->setInvalidDecl();
1851 Decl->setType(InitType);
1853 // In ARC, infer lifetime.
1854 // FIXME: ARC may want to turn this into 'const __unsafe_unretained' if
1855 // we're doing the equivalent of fast iteration.
1856 if (SemaRef.getLangOpts().ObjCAutoRefCount &&
1857 SemaRef.inferObjCARCLifetime(Decl))
1858 Decl->setInvalidDecl();
1860 SemaRef.AddInitializerToDecl(Decl, Init, /*DirectInit=*/false,
1861 /*TypeMayContainAuto=*/false);
1862 SemaRef.FinalizeDeclaration(Decl);
1863 SemaRef.CurContext->addHiddenDecl(Decl);
1869 /// Produce a note indicating which begin/end function was implicitly called
1870 /// by a C++11 for-range statement. This is often not obvious from the code,
1871 /// nor from the diagnostics produced when analysing the implicit expressions
1872 /// required in a for-range statement.
1873 void NoteForRangeBeginEndFunction(Sema &SemaRef, Expr *E,
1874 Sema::BeginEndFunction BEF) {
1875 CallExpr *CE = dyn_cast<CallExpr>(E);
1878 FunctionDecl *D = dyn_cast<FunctionDecl>(CE->getCalleeDecl());
1881 SourceLocation Loc = D->getLocation();
1883 std::string Description;
1884 bool IsTemplate = false;
1885 if (FunctionTemplateDecl *FunTmpl = D->getPrimaryTemplate()) {
1886 Description = SemaRef.getTemplateArgumentBindingsText(
1887 FunTmpl->getTemplateParameters(), *D->getTemplateSpecializationArgs());
1891 SemaRef.Diag(Loc, diag::note_for_range_begin_end)
1892 << BEF << IsTemplate << Description << E->getType();
1895 /// Build a variable declaration for a for-range statement.
1896 VarDecl *BuildForRangeVarDecl(Sema &SemaRef, SourceLocation Loc,
1897 QualType Type, const char *Name) {
1898 DeclContext *DC = SemaRef.CurContext;
1899 IdentifierInfo *II = &SemaRef.PP.getIdentifierTable().get(Name);
1900 TypeSourceInfo *TInfo = SemaRef.Context.getTrivialTypeSourceInfo(Type, Loc);
1901 VarDecl *Decl = VarDecl::Create(SemaRef.Context, DC, Loc, Loc, II, Type,
1903 Decl->setImplicit();
1909 static bool ObjCEnumerationCollection(Expr *Collection) {
1910 return !Collection->isTypeDependent()
1911 && Collection->getType()->getAs<ObjCObjectPointerType>() != nullptr;
1914 /// ActOnCXXForRangeStmt - Check and build a C++11 for-range statement.
1916 /// C++11 [stmt.ranged]:
1917 /// A range-based for statement is equivalent to
1920 /// auto && __range = range-init;
1921 /// for ( auto __begin = begin-expr,
1922 /// __end = end-expr;
1923 /// __begin != __end;
1925 /// for-range-declaration = *__begin;
1930 /// The body of the loop is not available yet, since it cannot be analysed until
1931 /// we have determined the type of the for-range-declaration.
1933 Sema::ActOnCXXForRangeStmt(SourceLocation ForLoc,
1934 Stmt *First, SourceLocation ColonLoc, Expr *Range,
1935 SourceLocation RParenLoc, BuildForRangeKind Kind) {
1939 if (Range && ObjCEnumerationCollection(Range))
1940 return ActOnObjCForCollectionStmt(ForLoc, First, Range, RParenLoc);
1942 DeclStmt *DS = dyn_cast<DeclStmt>(First);
1943 assert(DS && "first part of for range not a decl stmt");
1945 if (!DS->isSingleDecl()) {
1946 Diag(DS->getStartLoc(), diag::err_type_defined_in_for_range);
1950 Decl *LoopVar = DS->getSingleDecl();
1951 if (LoopVar->isInvalidDecl() || !Range ||
1952 DiagnoseUnexpandedParameterPack(Range, UPPC_Expression)) {
1953 LoopVar->setInvalidDecl();
1957 // Build auto && __range = range-init
1958 SourceLocation RangeLoc = Range->getLocStart();
1959 VarDecl *RangeVar = BuildForRangeVarDecl(*this, RangeLoc,
1960 Context.getAutoRRefDeductType(),
1962 if (FinishForRangeVarDecl(*this, RangeVar, Range, RangeLoc,
1963 diag::err_for_range_deduction_failure)) {
1964 LoopVar->setInvalidDecl();
1968 // Claim the type doesn't contain auto: we've already done the checking.
1969 DeclGroupPtrTy RangeGroup =
1970 BuildDeclaratorGroup(MutableArrayRef<Decl *>((Decl **)&RangeVar, 1),
1971 /*TypeMayContainAuto=*/ false);
1972 StmtResult RangeDecl = ActOnDeclStmt(RangeGroup, RangeLoc, RangeLoc);
1973 if (RangeDecl.isInvalid()) {
1974 LoopVar->setInvalidDecl();
1978 return BuildCXXForRangeStmt(ForLoc, ColonLoc, RangeDecl.get(),
1979 /*BeginEndDecl=*/nullptr, /*Cond=*/nullptr,
1980 /*Inc=*/nullptr, DS, RParenLoc, Kind);
1983 /// \brief Create the initialization, compare, and increment steps for
1984 /// the range-based for loop expression.
1985 /// This function does not handle array-based for loops,
1986 /// which are created in Sema::BuildCXXForRangeStmt.
1988 /// \returns a ForRangeStatus indicating success or what kind of error occurred.
1989 /// BeginExpr and EndExpr are set and FRS_Success is returned on success;
1990 /// CandidateSet and BEF are set and some non-success value is returned on
1992 static Sema::ForRangeStatus BuildNonArrayForRange(Sema &SemaRef, Scope *S,
1993 Expr *BeginRange, Expr *EndRange,
1997 SourceLocation ColonLoc,
1998 OverloadCandidateSet *CandidateSet,
1999 ExprResult *BeginExpr,
2000 ExprResult *EndExpr,
2001 Sema::BeginEndFunction *BEF) {
2002 DeclarationNameInfo BeginNameInfo(
2003 &SemaRef.PP.getIdentifierTable().get("begin"), ColonLoc);
2004 DeclarationNameInfo EndNameInfo(&SemaRef.PP.getIdentifierTable().get("end"),
2007 LookupResult BeginMemberLookup(SemaRef, BeginNameInfo,
2008 Sema::LookupMemberName);
2009 LookupResult EndMemberLookup(SemaRef, EndNameInfo, Sema::LookupMemberName);
2011 if (CXXRecordDecl *D = RangeType->getAsCXXRecordDecl()) {
2012 // - if _RangeT is a class type, the unqualified-ids begin and end are
2013 // looked up in the scope of class _RangeT as if by class member access
2014 // lookup (3.4.5), and if either (or both) finds at least one
2015 // declaration, begin-expr and end-expr are __range.begin() and
2016 // __range.end(), respectively;
2017 SemaRef.LookupQualifiedName(BeginMemberLookup, D);
2018 SemaRef.LookupQualifiedName(EndMemberLookup, D);
2020 if (BeginMemberLookup.empty() != EndMemberLookup.empty()) {
2021 SourceLocation RangeLoc = BeginVar->getLocation();
2022 *BEF = BeginMemberLookup.empty() ? Sema::BEF_end : Sema::BEF_begin;
2024 SemaRef.Diag(RangeLoc, diag::err_for_range_member_begin_end_mismatch)
2025 << RangeLoc << BeginRange->getType() << *BEF;
2026 return Sema::FRS_DiagnosticIssued;
2029 // - otherwise, begin-expr and end-expr are begin(__range) and
2030 // end(__range), respectively, where begin and end are looked up with
2031 // argument-dependent lookup (3.4.2). For the purposes of this name
2032 // lookup, namespace std is an associated namespace.
2036 *BEF = Sema::BEF_begin;
2037 Sema::ForRangeStatus RangeStatus =
2038 SemaRef.BuildForRangeBeginEndCall(S, ColonLoc, ColonLoc, BeginVar,
2039 Sema::BEF_begin, BeginNameInfo,
2040 BeginMemberLookup, CandidateSet,
2041 BeginRange, BeginExpr);
2043 if (RangeStatus != Sema::FRS_Success)
2045 if (FinishForRangeVarDecl(SemaRef, BeginVar, BeginExpr->get(), ColonLoc,
2046 diag::err_for_range_iter_deduction_failure)) {
2047 NoteForRangeBeginEndFunction(SemaRef, BeginExpr->get(), *BEF);
2048 return Sema::FRS_DiagnosticIssued;
2051 *BEF = Sema::BEF_end;
2053 SemaRef.BuildForRangeBeginEndCall(S, ColonLoc, ColonLoc, EndVar,
2054 Sema::BEF_end, EndNameInfo,
2055 EndMemberLookup, CandidateSet,
2057 if (RangeStatus != Sema::FRS_Success)
2059 if (FinishForRangeVarDecl(SemaRef, EndVar, EndExpr->get(), ColonLoc,
2060 diag::err_for_range_iter_deduction_failure)) {
2061 NoteForRangeBeginEndFunction(SemaRef, EndExpr->get(), *BEF);
2062 return Sema::FRS_DiagnosticIssued;
2064 return Sema::FRS_Success;
2067 /// Speculatively attempt to dereference an invalid range expression.
2068 /// If the attempt fails, this function will return a valid, null StmtResult
2069 /// and emit no diagnostics.
2070 static StmtResult RebuildForRangeWithDereference(Sema &SemaRef, Scope *S,
2071 SourceLocation ForLoc,
2073 SourceLocation ColonLoc,
2075 SourceLocation RangeLoc,
2076 SourceLocation RParenLoc) {
2077 // Determine whether we can rebuild the for-range statement with a
2078 // dereferenced range expression.
2079 ExprResult AdjustedRange;
2081 Sema::SFINAETrap Trap(SemaRef);
2083 AdjustedRange = SemaRef.BuildUnaryOp(S, RangeLoc, UO_Deref, Range);
2084 if (AdjustedRange.isInvalid())
2085 return StmtResult();
2088 SemaRef.ActOnCXXForRangeStmt(ForLoc, LoopVarDecl, ColonLoc,
2089 AdjustedRange.get(), RParenLoc,
2092 return StmtResult();
2095 // The attempt to dereference worked well enough that it could produce a valid
2096 // loop. Produce a fixit, and rebuild the loop with diagnostics enabled, in
2097 // case there are any other (non-fatal) problems with it.
2098 SemaRef.Diag(RangeLoc, diag::err_for_range_dereference)
2099 << Range->getType() << FixItHint::CreateInsertion(RangeLoc, "*");
2100 return SemaRef.ActOnCXXForRangeStmt(ForLoc, LoopVarDecl, ColonLoc,
2101 AdjustedRange.get(), RParenLoc,
2102 Sema::BFRK_Rebuild);
2106 /// RAII object to automatically invalidate a declaration if an error occurs.
2107 struct InvalidateOnErrorScope {
2108 InvalidateOnErrorScope(Sema &SemaRef, Decl *D, bool Enabled)
2109 : Trap(SemaRef.Diags), D(D), Enabled(Enabled) {}
2110 ~InvalidateOnErrorScope() {
2111 if (Enabled && Trap.hasErrorOccurred())
2112 D->setInvalidDecl();
2115 DiagnosticErrorTrap Trap;
2121 /// BuildCXXForRangeStmt - Build or instantiate a C++11 for-range statement.
2123 Sema::BuildCXXForRangeStmt(SourceLocation ForLoc, SourceLocation ColonLoc,
2124 Stmt *RangeDecl, Stmt *BeginEnd, Expr *Cond,
2125 Expr *Inc, Stmt *LoopVarDecl,
2126 SourceLocation RParenLoc, BuildForRangeKind Kind) {
2127 Scope *S = getCurScope();
2129 DeclStmt *RangeDS = cast<DeclStmt>(RangeDecl);
2130 VarDecl *RangeVar = cast<VarDecl>(RangeDS->getSingleDecl());
2131 QualType RangeVarType = RangeVar->getType();
2133 DeclStmt *LoopVarDS = cast<DeclStmt>(LoopVarDecl);
2134 VarDecl *LoopVar = cast<VarDecl>(LoopVarDS->getSingleDecl());
2136 // If we hit any errors, mark the loop variable as invalid if its type
2138 InvalidateOnErrorScope Invalidate(*this, LoopVar,
2139 LoopVar->getType()->isUndeducedType());
2141 StmtResult BeginEndDecl = BeginEnd;
2142 ExprResult NotEqExpr = Cond, IncrExpr = Inc;
2144 if (RangeVarType->isDependentType()) {
2145 // The range is implicitly used as a placeholder when it is dependent.
2146 RangeVar->markUsed(Context);
2148 // Deduce any 'auto's in the loop variable as 'DependentTy'. We'll fill
2149 // them in properly when we instantiate the loop.
2150 if (!LoopVar->isInvalidDecl() && Kind != BFRK_Check)
2151 LoopVar->setType(SubstAutoType(LoopVar->getType(), Context.DependentTy));
2152 } else if (!BeginEndDecl.get()) {
2153 SourceLocation RangeLoc = RangeVar->getLocation();
2155 const QualType RangeVarNonRefType = RangeVarType.getNonReferenceType();
2157 ExprResult BeginRangeRef = BuildDeclRefExpr(RangeVar, RangeVarNonRefType,
2158 VK_LValue, ColonLoc);
2159 if (BeginRangeRef.isInvalid())
2162 ExprResult EndRangeRef = BuildDeclRefExpr(RangeVar, RangeVarNonRefType,
2163 VK_LValue, ColonLoc);
2164 if (EndRangeRef.isInvalid())
2167 QualType AutoType = Context.getAutoDeductType();
2168 Expr *Range = RangeVar->getInit();
2171 QualType RangeType = Range->getType();
2173 if (RequireCompleteType(RangeLoc, RangeType,
2174 diag::err_for_range_incomplete_type))
2177 // Build auto __begin = begin-expr, __end = end-expr.
2178 VarDecl *BeginVar = BuildForRangeVarDecl(*this, ColonLoc, AutoType,
2180 VarDecl *EndVar = BuildForRangeVarDecl(*this, ColonLoc, AutoType,
2183 // Build begin-expr and end-expr and attach to __begin and __end variables.
2184 ExprResult BeginExpr, EndExpr;
2185 if (const ArrayType *UnqAT = RangeType->getAsArrayTypeUnsafe()) {
2186 // - if _RangeT is an array type, begin-expr and end-expr are __range and
2187 // __range + __bound, respectively, where __bound is the array bound. If
2188 // _RangeT is an array of unknown size or an array of incomplete type,
2189 // the program is ill-formed;
2191 // begin-expr is __range.
2192 BeginExpr = BeginRangeRef;
2193 if (FinishForRangeVarDecl(*this, BeginVar, BeginRangeRef.get(), ColonLoc,
2194 diag::err_for_range_iter_deduction_failure)) {
2195 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
2199 // Find the array bound.
2200 ExprResult BoundExpr;
2201 if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(UnqAT))
2202 BoundExpr = IntegerLiteral::Create(
2203 Context, CAT->getSize(), Context.getPointerDiffType(), RangeLoc);
2204 else if (const VariableArrayType *VAT =
2205 dyn_cast<VariableArrayType>(UnqAT))
2206 BoundExpr = VAT->getSizeExpr();
2208 // Can't be a DependentSizedArrayType or an IncompleteArrayType since
2209 // UnqAT is not incomplete and Range is not type-dependent.
2210 llvm_unreachable("Unexpected array type in for-range");
2213 // end-expr is __range + __bound.
2214 EndExpr = ActOnBinOp(S, ColonLoc, tok::plus, EndRangeRef.get(),
2216 if (EndExpr.isInvalid())
2218 if (FinishForRangeVarDecl(*this, EndVar, EndExpr.get(), ColonLoc,
2219 diag::err_for_range_iter_deduction_failure)) {
2220 NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
2224 OverloadCandidateSet CandidateSet(RangeLoc,
2225 OverloadCandidateSet::CSK_Normal);
2226 Sema::BeginEndFunction BEFFailure;
2227 ForRangeStatus RangeStatus =
2228 BuildNonArrayForRange(*this, S, BeginRangeRef.get(),
2229 EndRangeRef.get(), RangeType,
2230 BeginVar, EndVar, ColonLoc, &CandidateSet,
2231 &BeginExpr, &EndExpr, &BEFFailure);
2233 if (Kind == BFRK_Build && RangeStatus == FRS_NoViableFunction &&
2234 BEFFailure == BEF_begin) {
2235 // If the range is being built from an array parameter, emit a
2236 // a diagnostic that it is being treated as a pointer.
2237 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Range)) {
2238 if (ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(DRE->getDecl())) {
2239 QualType ArrayTy = PVD->getOriginalType();
2240 QualType PointerTy = PVD->getType();
2241 if (PointerTy->isPointerType() && ArrayTy->isArrayType()) {
2242 Diag(Range->getLocStart(), diag::err_range_on_array_parameter)
2243 << RangeLoc << PVD << ArrayTy << PointerTy;
2244 Diag(PVD->getLocation(), diag::note_declared_at);
2250 // If building the range failed, try dereferencing the range expression
2251 // unless a diagnostic was issued or the end function is problematic.
2252 StmtResult SR = RebuildForRangeWithDereference(*this, S, ForLoc,
2253 LoopVarDecl, ColonLoc,
2256 if (SR.isInvalid() || SR.isUsable())
2260 // Otherwise, emit diagnostics if we haven't already.
2261 if (RangeStatus == FRS_NoViableFunction) {
2262 Expr *Range = BEFFailure ? EndRangeRef.get() : BeginRangeRef.get();
2263 Diag(Range->getLocStart(), diag::err_for_range_invalid)
2264 << RangeLoc << Range->getType() << BEFFailure;
2265 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Range);
2267 // Return an error if no fix was discovered.
2268 if (RangeStatus != FRS_Success)
2272 assert(!BeginExpr.isInvalid() && !EndExpr.isInvalid() &&
2273 "invalid range expression in for loop");
2275 // C++11 [dcl.spec.auto]p7: BeginType and EndType must be the same.
2276 QualType BeginType = BeginVar->getType(), EndType = EndVar->getType();
2277 if (!Context.hasSameType(BeginType, EndType)) {
2278 Diag(RangeLoc, diag::err_for_range_begin_end_types_differ)
2279 << BeginType << EndType;
2280 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
2281 NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
2284 Decl *BeginEndDecls[] = { BeginVar, EndVar };
2285 // Claim the type doesn't contain auto: we've already done the checking.
2286 DeclGroupPtrTy BeginEndGroup =
2287 BuildDeclaratorGroup(MutableArrayRef<Decl *>(BeginEndDecls, 2),
2288 /*TypeMayContainAuto=*/ false);
2289 BeginEndDecl = ActOnDeclStmt(BeginEndGroup, ColonLoc, ColonLoc);
2291 const QualType BeginRefNonRefType = BeginType.getNonReferenceType();
2292 ExprResult BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType,
2293 VK_LValue, ColonLoc);
2294 if (BeginRef.isInvalid())
2297 ExprResult EndRef = BuildDeclRefExpr(EndVar, EndType.getNonReferenceType(),
2298 VK_LValue, ColonLoc);
2299 if (EndRef.isInvalid())
2302 // Build and check __begin != __end expression.
2303 NotEqExpr = ActOnBinOp(S, ColonLoc, tok::exclaimequal,
2304 BeginRef.get(), EndRef.get());
2305 NotEqExpr = ActOnBooleanCondition(S, ColonLoc, NotEqExpr.get());
2306 NotEqExpr = ActOnFinishFullExpr(NotEqExpr.get());
2307 if (NotEqExpr.isInvalid()) {
2308 Diag(RangeLoc, diag::note_for_range_invalid_iterator)
2309 << RangeLoc << 0 << BeginRangeRef.get()->getType();
2310 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
2311 if (!Context.hasSameType(BeginType, EndType))
2312 NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
2316 // Build and check ++__begin expression.
2317 BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType,
2318 VK_LValue, ColonLoc);
2319 if (BeginRef.isInvalid())
2322 IncrExpr = ActOnUnaryOp(S, ColonLoc, tok::plusplus, BeginRef.get());
2323 IncrExpr = ActOnFinishFullExpr(IncrExpr.get());
2324 if (IncrExpr.isInvalid()) {
2325 Diag(RangeLoc, diag::note_for_range_invalid_iterator)
2326 << RangeLoc << 2 << BeginRangeRef.get()->getType() ;
2327 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
2331 // Build and check *__begin expression.
2332 BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType,
2333 VK_LValue, ColonLoc);
2334 if (BeginRef.isInvalid())
2337 ExprResult DerefExpr = ActOnUnaryOp(S, ColonLoc, tok::star, BeginRef.get());
2338 if (DerefExpr.isInvalid()) {
2339 Diag(RangeLoc, diag::note_for_range_invalid_iterator)
2340 << RangeLoc << 1 << BeginRangeRef.get()->getType();
2341 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
2345 // Attach *__begin as initializer for VD. Don't touch it if we're just
2346 // trying to determine whether this would be a valid range.
2347 if (!LoopVar->isInvalidDecl() && Kind != BFRK_Check) {
2348 AddInitializerToDecl(LoopVar, DerefExpr.get(), /*DirectInit=*/false,
2349 /*TypeMayContainAuto=*/true);
2350 if (LoopVar->isInvalidDecl())
2351 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
2355 // Don't bother to actually allocate the result if we're just trying to
2356 // determine whether it would be valid.
2357 if (Kind == BFRK_Check)
2358 return StmtResult();
2360 return new (Context) CXXForRangeStmt(
2361 RangeDS, cast_or_null<DeclStmt>(BeginEndDecl.get()), NotEqExpr.get(),
2362 IncrExpr.get(), LoopVarDS, /*Body=*/nullptr, ForLoc, ColonLoc, RParenLoc);
2365 /// FinishObjCForCollectionStmt - Attach the body to a objective-C foreach
2367 StmtResult Sema::FinishObjCForCollectionStmt(Stmt *S, Stmt *B) {
2370 ObjCForCollectionStmt * ForStmt = cast<ObjCForCollectionStmt>(S);
2372 ForStmt->setBody(B);
2376 // Warn when the loop variable is a const reference that creates a copy.
2377 // Suggest using the non-reference type for copies. If a copy can be prevented
2378 // suggest the const reference type that would do so.
2379 // For instance, given "for (const &Foo : Range)", suggest
2380 // "for (const Foo : Range)" to denote a copy is made for the loop. If
2381 // possible, also suggest "for (const &Bar : Range)" if this type prevents
2382 // the copy altogether.
2383 static void DiagnoseForRangeReferenceVariableCopies(Sema &SemaRef,
2385 QualType RangeInitType) {
2386 const Expr *InitExpr = VD->getInit();
2390 QualType VariableType = VD->getType();
2392 const MaterializeTemporaryExpr *MTE =
2393 dyn_cast<MaterializeTemporaryExpr>(InitExpr);
2399 const Expr *E = MTE->GetTemporaryExpr()->IgnoreImpCasts();
2401 // Searching for either UnaryOperator for dereference of a pointer or
2402 // CXXOperatorCallExpr for handling iterators.
2403 while (!isa<CXXOperatorCallExpr>(E) && !isa<UnaryOperator>(E)) {
2404 if (const CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(E)) {
2406 } else if (const CXXMemberCallExpr *Call = dyn_cast<CXXMemberCallExpr>(E)) {
2407 const MemberExpr *ME = cast<MemberExpr>(Call->getCallee());
2410 const MaterializeTemporaryExpr *MTE = cast<MaterializeTemporaryExpr>(E);
2411 E = MTE->GetTemporaryExpr();
2413 E = E->IgnoreImpCasts();
2416 bool ReturnsReference = false;
2417 if (isa<UnaryOperator>(E)) {
2418 ReturnsReference = true;
2420 const CXXOperatorCallExpr *Call = cast<CXXOperatorCallExpr>(E);
2421 const FunctionDecl *FD = Call->getDirectCallee();
2422 QualType ReturnType = FD->getReturnType();
2423 ReturnsReference = ReturnType->isReferenceType();
2426 if (ReturnsReference) {
2427 // Loop variable creates a temporary. Suggest either to go with
2428 // non-reference loop variable to indiciate a copy is made, or
2429 // the correct time to bind a const reference.
2430 SemaRef.Diag(VD->getLocation(), diag::warn_for_range_const_reference_copy)
2431 << VD << VariableType << E->getType();
2432 QualType NonReferenceType = VariableType.getNonReferenceType();
2433 NonReferenceType.removeLocalConst();
2434 QualType NewReferenceType =
2435 SemaRef.Context.getLValueReferenceType(E->getType().withConst());
2436 SemaRef.Diag(VD->getLocStart(), diag::note_use_type_or_non_reference)
2437 << NonReferenceType << NewReferenceType << VD->getSourceRange();
2439 // The range always returns a copy, so a temporary is always created.
2440 // Suggest removing the reference from the loop variable.
2441 SemaRef.Diag(VD->getLocation(), diag::warn_for_range_variable_always_copy)
2442 << VD << RangeInitType;
2443 QualType NonReferenceType = VariableType.getNonReferenceType();
2444 NonReferenceType.removeLocalConst();
2445 SemaRef.Diag(VD->getLocStart(), diag::note_use_non_reference_type)
2446 << NonReferenceType << VD->getSourceRange();
2450 // Warns when the loop variable can be changed to a reference type to
2451 // prevent a copy. For instance, if given "for (const Foo x : Range)" suggest
2452 // "for (const Foo &x : Range)" if this form does not make a copy.
2453 static void DiagnoseForRangeConstVariableCopies(Sema &SemaRef,
2454 const VarDecl *VD) {
2455 const Expr *InitExpr = VD->getInit();
2459 QualType VariableType = VD->getType();
2461 if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(InitExpr)) {
2462 if (!CE->getConstructor()->isCopyConstructor())
2464 } else if (const CastExpr *CE = dyn_cast<CastExpr>(InitExpr)) {
2465 if (CE->getCastKind() != CK_LValueToRValue)
2471 // TODO: Determine a maximum size that a POD type can be before a diagnostic
2472 // should be emitted. Also, only ignore POD types with trivial copy
2474 if (VariableType.isPODType(SemaRef.Context))
2477 // Suggest changing from a const variable to a const reference variable
2478 // if doing so will prevent a copy.
2479 SemaRef.Diag(VD->getLocation(), diag::warn_for_range_copy)
2480 << VD << VariableType << InitExpr->getType();
2481 SemaRef.Diag(VD->getLocStart(), diag::note_use_reference_type)
2482 << SemaRef.Context.getLValueReferenceType(VariableType)
2483 << VD->getSourceRange();
2486 /// DiagnoseForRangeVariableCopies - Diagnose three cases and fixes for them.
2487 /// 1) for (const foo &x : foos) where foos only returns a copy. Suggest
2488 /// using "const foo x" to show that a copy is made
2489 /// 2) for (const bar &x : foos) where bar is a temporary intialized by bar.
2490 /// Suggest either "const bar x" to keep the copying or "const foo& x" to
2491 /// prevent the copy.
2492 /// 3) for (const foo x : foos) where x is constructed from a reference foo.
2493 /// Suggest "const foo &x" to prevent the copy.
2494 static void DiagnoseForRangeVariableCopies(Sema &SemaRef,
2495 const CXXForRangeStmt *ForStmt) {
2496 if (SemaRef.Diags.isIgnored(diag::warn_for_range_const_reference_copy,
2497 ForStmt->getLocStart()) &&
2498 SemaRef.Diags.isIgnored(diag::warn_for_range_variable_always_copy,
2499 ForStmt->getLocStart()) &&
2500 SemaRef.Diags.isIgnored(diag::warn_for_range_copy,
2501 ForStmt->getLocStart())) {
2505 const VarDecl *VD = ForStmt->getLoopVariable();
2509 QualType VariableType = VD->getType();
2511 if (VariableType->isIncompleteType())
2514 const Expr *InitExpr = VD->getInit();
2518 if (VariableType->isReferenceType()) {
2519 DiagnoseForRangeReferenceVariableCopies(SemaRef, VD,
2520 ForStmt->getRangeInit()->getType());
2521 } else if (VariableType.isConstQualified()) {
2522 DiagnoseForRangeConstVariableCopies(SemaRef, VD);
2526 /// FinishCXXForRangeStmt - Attach the body to a C++0x for-range statement.
2527 /// This is a separate step from ActOnCXXForRangeStmt because analysis of the
2528 /// body cannot be performed until after the type of the range variable is
2530 StmtResult Sema::FinishCXXForRangeStmt(Stmt *S, Stmt *B) {
2534 if (isa<ObjCForCollectionStmt>(S))
2535 return FinishObjCForCollectionStmt(S, B);
2537 CXXForRangeStmt *ForStmt = cast<CXXForRangeStmt>(S);
2538 ForStmt->setBody(B);
2540 DiagnoseEmptyStmtBody(ForStmt->getRParenLoc(), B,
2541 diag::warn_empty_range_based_for_body);
2543 DiagnoseForRangeVariableCopies(*this, ForStmt);
2548 StmtResult Sema::ActOnGotoStmt(SourceLocation GotoLoc,
2549 SourceLocation LabelLoc,
2550 LabelDecl *TheDecl) {
2551 getCurFunction()->setHasBranchIntoScope();
2552 TheDecl->markUsed(Context);
2553 return new (Context) GotoStmt(TheDecl, GotoLoc, LabelLoc);
2557 Sema::ActOnIndirectGotoStmt(SourceLocation GotoLoc, SourceLocation StarLoc,
2559 // Convert operand to void*
2560 if (!E->isTypeDependent()) {
2561 QualType ETy = E->getType();
2562 QualType DestTy = Context.getPointerType(Context.VoidTy.withConst());
2563 ExprResult ExprRes = E;
2564 AssignConvertType ConvTy =
2565 CheckSingleAssignmentConstraints(DestTy, ExprRes);
2566 if (ExprRes.isInvalid())
2569 if (DiagnoseAssignmentResult(ConvTy, StarLoc, DestTy, ETy, E, AA_Passing))
2573 ExprResult ExprRes = ActOnFinishFullExpr(E);
2574 if (ExprRes.isInvalid())
2578 getCurFunction()->setHasIndirectGoto();
2580 return new (Context) IndirectGotoStmt(GotoLoc, StarLoc, E);
2583 static void CheckJumpOutOfSEHFinally(Sema &S, SourceLocation Loc,
2584 const Scope &DestScope) {
2585 if (!S.CurrentSEHFinally.empty() &&
2586 DestScope.Contains(*S.CurrentSEHFinally.back())) {
2587 S.Diag(Loc, diag::warn_jump_out_of_seh_finally);
2592 Sema::ActOnContinueStmt(SourceLocation ContinueLoc, Scope *CurScope) {
2593 Scope *S = CurScope->getContinueParent();
2595 // C99 6.8.6.2p1: A break shall appear only in or as a loop body.
2596 return StmtError(Diag(ContinueLoc, diag::err_continue_not_in_loop));
2598 CheckJumpOutOfSEHFinally(*this, ContinueLoc, *S);
2600 return new (Context) ContinueStmt(ContinueLoc);
2604 Sema::ActOnBreakStmt(SourceLocation BreakLoc, Scope *CurScope) {
2605 Scope *S = CurScope->getBreakParent();
2607 // C99 6.8.6.3p1: A break shall appear only in or as a switch/loop body.
2608 return StmtError(Diag(BreakLoc, diag::err_break_not_in_loop_or_switch));
2610 if (S->isOpenMPLoopScope())
2611 return StmtError(Diag(BreakLoc, diag::err_omp_loop_cannot_use_stmt)
2613 CheckJumpOutOfSEHFinally(*this, BreakLoc, *S);
2615 return new (Context) BreakStmt(BreakLoc);
2618 /// \brief Determine whether the given expression is a candidate for
2619 /// copy elision in either a return statement or a throw expression.
2621 /// \param ReturnType If we're determining the copy elision candidate for
2622 /// a return statement, this is the return type of the function. If we're
2623 /// determining the copy elision candidate for a throw expression, this will
2626 /// \param E The expression being returned from the function or block, or
2629 /// \param AllowFunctionParameter Whether we allow function parameters to
2630 /// be considered NRVO candidates. C++ prohibits this for NRVO itself, but
2631 /// we re-use this logic to determine whether we should try to move as part of
2632 /// a return or throw (which does allow function parameters).
2634 /// \returns The NRVO candidate variable, if the return statement may use the
2635 /// NRVO, or NULL if there is no such candidate.
2636 VarDecl *Sema::getCopyElisionCandidate(QualType ReturnType,
2638 bool AllowFunctionParameter) {
2639 if (!getLangOpts().CPlusPlus)
2642 // - in a return statement in a function [where] ...
2643 // ... the expression is the name of a non-volatile automatic object ...
2644 DeclRefExpr *DR = dyn_cast<DeclRefExpr>(E->IgnoreParens());
2645 if (!DR || DR->refersToEnclosingVariableOrCapture())
2647 VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl());
2651 if (isCopyElisionCandidate(ReturnType, VD, AllowFunctionParameter))
2656 bool Sema::isCopyElisionCandidate(QualType ReturnType, const VarDecl *VD,
2657 bool AllowFunctionParameter) {
2658 QualType VDType = VD->getType();
2659 // - in a return statement in a function with ...
2660 // ... a class return type ...
2661 if (!ReturnType.isNull() && !ReturnType->isDependentType()) {
2662 if (!ReturnType->isRecordType())
2664 // ... the same cv-unqualified type as the function return type ...
2665 if (!VDType->isDependentType() &&
2666 !Context.hasSameUnqualifiedType(ReturnType, VDType))
2670 // ...object (other than a function or catch-clause parameter)...
2671 if (VD->getKind() != Decl::Var &&
2672 !(AllowFunctionParameter && VD->getKind() == Decl::ParmVar))
2674 if (VD->isExceptionVariable()) return false;
2677 if (!VD->hasLocalStorage()) return false;
2679 // ...non-volatile...
2680 if (VD->getType().isVolatileQualified()) return false;
2682 // __block variables can't be allocated in a way that permits NRVO.
2683 if (VD->hasAttr<BlocksAttr>()) return false;
2685 // Variables with higher required alignment than their type's ABI
2686 // alignment cannot use NRVO.
2687 if (!VD->getType()->isDependentType() && VD->hasAttr<AlignedAttr>() &&
2688 Context.getDeclAlign(VD) > Context.getTypeAlignInChars(VD->getType()))
2694 /// \brief Perform the initialization of a potentially-movable value, which
2695 /// is the result of return value.
2697 /// This routine implements C++0x [class.copy]p33, which attempts to treat
2698 /// returned lvalues as rvalues in certain cases (to prefer move construction),
2699 /// then falls back to treating them as lvalues if that failed.
2701 Sema::PerformMoveOrCopyInitialization(const InitializedEntity &Entity,
2702 const VarDecl *NRVOCandidate,
2703 QualType ResultType,
2706 // C++0x [class.copy]p33:
2707 // When the criteria for elision of a copy operation are met or would
2708 // be met save for the fact that the source object is a function
2709 // parameter, and the object to be copied is designated by an lvalue,
2710 // overload resolution to select the constructor for the copy is first
2711 // performed as if the object were designated by an rvalue.
2712 ExprResult Res = ExprError();
2714 (NRVOCandidate || getCopyElisionCandidate(ResultType, Value, true))) {
2715 ImplicitCastExpr AsRvalue(ImplicitCastExpr::OnStack,
2716 Value->getType(), CK_NoOp, Value, VK_XValue);
2718 Expr *InitExpr = &AsRvalue;
2719 InitializationKind Kind
2720 = InitializationKind::CreateCopy(Value->getLocStart(),
2721 Value->getLocStart());
2722 InitializationSequence Seq(*this, Entity, Kind, InitExpr);
2724 // [...] If overload resolution fails, or if the type of the first
2725 // parameter of the selected constructor is not an rvalue reference
2726 // to the object's type (possibly cv-qualified), overload resolution
2727 // is performed again, considering the object as an lvalue.
2729 for (InitializationSequence::step_iterator Step = Seq.step_begin(),
2730 StepEnd = Seq.step_end();
2731 Step != StepEnd; ++Step) {
2732 if (Step->Kind != InitializationSequence::SK_ConstructorInitialization)
2735 CXXConstructorDecl *Constructor
2736 = cast<CXXConstructorDecl>(Step->Function.Function);
2738 const RValueReferenceType *RRefType
2739 = Constructor->getParamDecl(0)->getType()
2740 ->getAs<RValueReferenceType>();
2742 // If we don't meet the criteria, break out now.
2744 !Context.hasSameUnqualifiedType(RRefType->getPointeeType(),
2745 Context.getTypeDeclType(Constructor->getParent())))
2748 // Promote "AsRvalue" to the heap, since we now need this
2749 // expression node to persist.
2750 Value = ImplicitCastExpr::Create(Context, Value->getType(),
2751 CK_NoOp, Value, nullptr, VK_XValue);
2753 // Complete type-checking the initialization of the return type
2754 // using the constructor we found.
2755 Res = Seq.Perform(*this, Entity, Kind, Value);
2760 // Either we didn't meet the criteria for treating an lvalue as an rvalue,
2761 // above, or overload resolution failed. Either way, we need to try
2762 // (again) now with the return value expression as written.
2763 if (Res.isInvalid())
2764 Res = PerformCopyInitialization(Entity, SourceLocation(), Value);
2769 /// \brief Determine whether the declared return type of the specified function
2770 /// contains 'auto'.
2771 static bool hasDeducedReturnType(FunctionDecl *FD) {
2772 const FunctionProtoType *FPT =
2773 FD->getTypeSourceInfo()->getType()->castAs<FunctionProtoType>();
2774 return FPT->getReturnType()->isUndeducedType();
2777 /// ActOnCapScopeReturnStmt - Utility routine to type-check return statements
2778 /// for capturing scopes.
2781 Sema::ActOnCapScopeReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) {
2782 // If this is the first return we've seen, infer the return type.
2783 // [expr.prim.lambda]p4 in C++11; block literals follow the same rules.
2784 CapturingScopeInfo *CurCap = cast<CapturingScopeInfo>(getCurFunction());
2785 QualType FnRetType = CurCap->ReturnType;
2786 LambdaScopeInfo *CurLambda = dyn_cast<LambdaScopeInfo>(CurCap);
2788 if (CurLambda && hasDeducedReturnType(CurLambda->CallOperator)) {
2789 // In C++1y, the return type may involve 'auto'.
2790 // FIXME: Blocks might have a return type of 'auto' explicitly specified.
2791 FunctionDecl *FD = CurLambda->CallOperator;
2792 if (CurCap->ReturnType.isNull())
2793 CurCap->ReturnType = FD->getReturnType();
2795 AutoType *AT = CurCap->ReturnType->getContainedAutoType();
2796 assert(AT && "lost auto type from lambda return type");
2797 if (DeduceFunctionTypeFromReturnExpr(FD, ReturnLoc, RetValExp, AT)) {
2798 FD->setInvalidDecl();
2801 CurCap->ReturnType = FnRetType = FD->getReturnType();
2802 } else if (CurCap->HasImplicitReturnType) {
2803 // For blocks/lambdas with implicit return types, we check each return
2804 // statement individually, and deduce the common return type when the block
2805 // or lambda is completed.
2806 // FIXME: Fold this into the 'auto' codepath above.
2807 if (RetValExp && !isa<InitListExpr>(RetValExp)) {
2808 ExprResult Result = DefaultFunctionArrayLvalueConversion(RetValExp);
2809 if (Result.isInvalid())
2811 RetValExp = Result.get();
2813 // DR1048: even prior to C++14, we should use the 'auto' deduction rules
2814 // when deducing a return type for a lambda-expression (or by extension
2815 // for a block). These rules differ from the stated C++11 rules only in
2816 // that they remove top-level cv-qualifiers.
2817 if (!CurContext->isDependentContext())
2818 FnRetType = RetValExp->getType().getUnqualifiedType();
2820 FnRetType = CurCap->ReturnType = Context.DependentTy;
2823 // C++11 [expr.lambda.prim]p4 bans inferring the result from an
2824 // initializer list, because it is not an expression (even
2825 // though we represent it as one). We still deduce 'void'.
2826 Diag(ReturnLoc, diag::err_lambda_return_init_list)
2827 << RetValExp->getSourceRange();
2830 FnRetType = Context.VoidTy;
2833 // Although we'll properly infer the type of the block once it's completed,
2834 // make sure we provide a return type now for better error recovery.
2835 if (CurCap->ReturnType.isNull())
2836 CurCap->ReturnType = FnRetType;
2838 assert(!FnRetType.isNull());
2840 if (BlockScopeInfo *CurBlock = dyn_cast<BlockScopeInfo>(CurCap)) {
2841 if (CurBlock->FunctionType->getAs<FunctionType>()->getNoReturnAttr()) {
2842 Diag(ReturnLoc, diag::err_noreturn_block_has_return_expr);
2845 } else if (CapturedRegionScopeInfo *CurRegion =
2846 dyn_cast<CapturedRegionScopeInfo>(CurCap)) {
2847 Diag(ReturnLoc, diag::err_return_in_captured_stmt) << CurRegion->getRegionName();
2850 assert(CurLambda && "unknown kind of captured scope");
2851 if (CurLambda->CallOperator->getType()->getAs<FunctionType>()
2852 ->getNoReturnAttr()) {
2853 Diag(ReturnLoc, diag::err_noreturn_lambda_has_return_expr);
2858 // Otherwise, verify that this result type matches the previous one. We are
2859 // pickier with blocks than for normal functions because we don't have GCC
2860 // compatibility to worry about here.
2861 const VarDecl *NRVOCandidate = nullptr;
2862 if (FnRetType->isDependentType()) {
2863 // Delay processing for now. TODO: there are lots of dependent
2864 // types we can conclusively prove aren't void.
2865 } else if (FnRetType->isVoidType()) {
2866 if (RetValExp && !isa<InitListExpr>(RetValExp) &&
2867 !(getLangOpts().CPlusPlus &&
2868 (RetValExp->isTypeDependent() ||
2869 RetValExp->getType()->isVoidType()))) {
2870 if (!getLangOpts().CPlusPlus &&
2871 RetValExp->getType()->isVoidType())
2872 Diag(ReturnLoc, diag::ext_return_has_void_expr) << "literal" << 2;
2874 Diag(ReturnLoc, diag::err_return_block_has_expr);
2875 RetValExp = nullptr;
2878 } else if (!RetValExp) {
2879 return StmtError(Diag(ReturnLoc, diag::err_block_return_missing_expr));
2880 } else if (!RetValExp->isTypeDependent()) {
2881 // we have a non-void block with an expression, continue checking
2883 // C99 6.8.6.4p3(136): The return statement is not an assignment. The
2884 // overlap restriction of subclause 6.5.16.1 does not apply to the case of
2887 // In C++ the return statement is handled via a copy initialization.
2888 // the C version of which boils down to CheckSingleAssignmentConstraints.
2889 NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false);
2890 InitializedEntity Entity = InitializedEntity::InitializeResult(ReturnLoc,
2892 NRVOCandidate != nullptr);
2893 ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRVOCandidate,
2894 FnRetType, RetValExp);
2895 if (Res.isInvalid()) {
2896 // FIXME: Cleanup temporaries here, anyway?
2899 RetValExp = Res.get();
2900 CheckReturnValExpr(RetValExp, FnRetType, ReturnLoc);
2902 NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false);
2906 ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc);
2909 RetValExp = ER.get();
2911 ReturnStmt *Result = new (Context) ReturnStmt(ReturnLoc, RetValExp,
2914 // If we need to check for the named return value optimization,
2915 // or if we need to infer the return type,
2916 // save the return statement in our scope for later processing.
2917 if (CurCap->HasImplicitReturnType || NRVOCandidate)
2918 FunctionScopes.back()->Returns.push_back(Result);
2924 /// \brief Marks all typedefs in all local classes in a type referenced.
2926 /// In a function like
2928 /// struct S { typedef int a; };
2932 /// the local type escapes and could be referenced in some TUs but not in
2933 /// others. Pretend that all local typedefs are always referenced, to not warn
2934 /// on this. This isn't necessary if f has internal linkage, or the typedef
2936 class LocalTypedefNameReferencer
2937 : public RecursiveASTVisitor<LocalTypedefNameReferencer> {
2939 LocalTypedefNameReferencer(Sema &S) : S(S) {}
2940 bool VisitRecordType(const RecordType *RT);
2944 bool LocalTypedefNameReferencer::VisitRecordType(const RecordType *RT) {
2945 auto *R = dyn_cast<CXXRecordDecl>(RT->getDecl());
2946 if (!R || !R->isLocalClass() || !R->isLocalClass()->isExternallyVisible() ||
2947 R->isDependentType())
2949 for (auto *TmpD : R->decls())
2950 if (auto *T = dyn_cast<TypedefNameDecl>(TmpD))
2951 if (T->getAccess() != AS_private || R->hasFriends())
2952 S.MarkAnyDeclReferenced(T->getLocation(), T, /*OdrUse=*/false);
2957 TypeLoc Sema::getReturnTypeLoc(FunctionDecl *FD) const {
2958 TypeLoc TL = FD->getTypeSourceInfo()->getTypeLoc().IgnoreParens();
2959 while (auto ATL = TL.getAs<AttributedTypeLoc>())
2960 TL = ATL.getModifiedLoc().IgnoreParens();
2961 return TL.castAs<FunctionProtoTypeLoc>().getReturnLoc();
2964 /// Deduce the return type for a function from a returned expression, per
2965 /// C++1y [dcl.spec.auto]p6.
2966 bool Sema::DeduceFunctionTypeFromReturnExpr(FunctionDecl *FD,
2967 SourceLocation ReturnLoc,
2970 TypeLoc OrigResultType = getReturnTypeLoc(FD);
2973 if (RetExpr && isa<InitListExpr>(RetExpr)) {
2974 // If the deduction is for a return statement and the initializer is
2975 // a braced-init-list, the program is ill-formed.
2976 Diag(RetExpr->getExprLoc(),
2977 getCurLambda() ? diag::err_lambda_return_init_list
2978 : diag::err_auto_fn_return_init_list)
2979 << RetExpr->getSourceRange();
2983 if (FD->isDependentContext()) {
2984 // C++1y [dcl.spec.auto]p12:
2985 // Return type deduction [...] occurs when the definition is
2986 // instantiated even if the function body contains a return
2987 // statement with a non-type-dependent operand.
2988 assert(AT->isDeduced() && "should have deduced to dependent type");
2990 } else if (RetExpr) {
2991 // If the deduction is for a return statement and the initializer is
2992 // a braced-init-list, the program is ill-formed.
2993 if (isa<InitListExpr>(RetExpr)) {
2994 Diag(RetExpr->getExprLoc(), diag::err_auto_fn_return_init_list);
2998 // Otherwise, [...] deduce a value for U using the rules of template
2999 // argument deduction.
3000 DeduceAutoResult DAR = DeduceAutoType(OrigResultType, RetExpr, Deduced);
3002 if (DAR == DAR_Failed && !FD->isInvalidDecl())
3003 Diag(RetExpr->getExprLoc(), diag::err_auto_fn_deduction_failure)
3004 << OrigResultType.getType() << RetExpr->getType();
3006 if (DAR != DAR_Succeeded)
3009 // If a local type is part of the returned type, mark its fields as
3011 LocalTypedefNameReferencer Referencer(*this);
3012 Referencer.TraverseType(RetExpr->getType());
3014 // In the case of a return with no operand, the initializer is considered
3017 // Deduction here can only succeed if the return type is exactly 'cv auto'
3018 // or 'decltype(auto)', so just check for that case directly.
3019 if (!OrigResultType.getType()->getAs<AutoType>()) {
3020 Diag(ReturnLoc, diag::err_auto_fn_return_void_but_not_auto)
3021 << OrigResultType.getType();
3024 // We always deduce U = void in this case.
3025 Deduced = SubstAutoType(OrigResultType.getType(), Context.VoidTy);
3026 if (Deduced.isNull())
3030 // If a function with a declared return type that contains a placeholder type
3031 // has multiple return statements, the return type is deduced for each return
3032 // statement. [...] if the type deduced is not the same in each deduction,
3033 // the program is ill-formed.
3034 if (AT->isDeduced() && !FD->isInvalidDecl()) {
3035 AutoType *NewAT = Deduced->getContainedAutoType();
3036 if (!FD->isDependentContext() &&
3037 !Context.hasSameType(AT->getDeducedType(), NewAT->getDeducedType())) {
3038 const LambdaScopeInfo *LambdaSI = getCurLambda();
3039 if (LambdaSI && LambdaSI->HasImplicitReturnType) {
3040 Diag(ReturnLoc, diag::err_typecheck_missing_return_type_incompatible)
3041 << NewAT->getDeducedType() << AT->getDeducedType()
3042 << true /*IsLambda*/;
3044 Diag(ReturnLoc, diag::err_auto_fn_different_deductions)
3045 << (AT->isDecltypeAuto() ? 1 : 0)
3046 << NewAT->getDeducedType() << AT->getDeducedType();
3050 } else if (!FD->isInvalidDecl()) {
3051 // Update all declarations of the function to have the deduced return type.
3052 Context.adjustDeducedFunctionResultType(FD, Deduced);
3059 Sema::ActOnReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp,
3061 StmtResult R = BuildReturnStmt(ReturnLoc, RetValExp);
3062 if (R.isInvalid()) {
3067 const_cast<VarDecl*>(cast<ReturnStmt>(R.get())->getNRVOCandidate())) {
3068 CurScope->addNRVOCandidate(VD);
3070 CurScope->setNoNRVO();
3073 CheckJumpOutOfSEHFinally(*this, ReturnLoc, *CurScope->getFnParent());
3078 StmtResult Sema::BuildReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) {
3079 // Check for unexpanded parameter packs.
3080 if (RetValExp && DiagnoseUnexpandedParameterPack(RetValExp))
3083 if (isa<CapturingScopeInfo>(getCurFunction()))
3084 return ActOnCapScopeReturnStmt(ReturnLoc, RetValExp);
3087 QualType RelatedRetType;
3088 const AttrVec *Attrs = nullptr;
3089 bool isObjCMethod = false;
3091 if (const FunctionDecl *FD = getCurFunctionDecl()) {
3092 FnRetType = FD->getReturnType();
3094 Attrs = &FD->getAttrs();
3095 if (FD->isNoReturn())
3096 Diag(ReturnLoc, diag::warn_noreturn_function_has_return_expr)
3097 << FD->getDeclName();
3098 } else if (ObjCMethodDecl *MD = getCurMethodDecl()) {
3099 FnRetType = MD->getReturnType();
3100 isObjCMethod = true;
3102 Attrs = &MD->getAttrs();
3103 if (MD->hasRelatedResultType() && MD->getClassInterface()) {
3104 // In the implementation of a method with a related return type, the
3105 // type used to type-check the validity of return statements within the
3106 // method body is a pointer to the type of the class being implemented.
3107 RelatedRetType = Context.getObjCInterfaceType(MD->getClassInterface());
3108 RelatedRetType = Context.getObjCObjectPointerType(RelatedRetType);
3110 } else // If we don't have a function/method context, bail.
3113 // FIXME: Add a flag to the ScopeInfo to indicate whether we're performing
3115 if (getLangOpts().CPlusPlus14) {
3116 if (AutoType *AT = FnRetType->getContainedAutoType()) {
3117 FunctionDecl *FD = cast<FunctionDecl>(CurContext);
3118 if (DeduceFunctionTypeFromReturnExpr(FD, ReturnLoc, RetValExp, AT)) {
3119 FD->setInvalidDecl();
3122 FnRetType = FD->getReturnType();
3127 bool HasDependentReturnType = FnRetType->isDependentType();
3129 ReturnStmt *Result = nullptr;
3130 if (FnRetType->isVoidType()) {
3132 if (isa<InitListExpr>(RetValExp)) {
3133 // We simply never allow init lists as the return value of void
3134 // functions. This is compatible because this was never allowed before,
3135 // so there's no legacy code to deal with.
3136 NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
3137 int FunctionKind = 0;
3138 if (isa<ObjCMethodDecl>(CurDecl))
3140 else if (isa<CXXConstructorDecl>(CurDecl))
3142 else if (isa<CXXDestructorDecl>(CurDecl))
3145 Diag(ReturnLoc, diag::err_return_init_list)
3146 << CurDecl->getDeclName() << FunctionKind
3147 << RetValExp->getSourceRange();
3149 // Drop the expression.
3150 RetValExp = nullptr;
3151 } else if (!RetValExp->isTypeDependent()) {
3152 // C99 6.8.6.4p1 (ext_ since GCC warns)
3153 unsigned D = diag::ext_return_has_expr;
3154 if (RetValExp->getType()->isVoidType()) {
3155 NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
3156 if (isa<CXXConstructorDecl>(CurDecl) ||
3157 isa<CXXDestructorDecl>(CurDecl))
3158 D = diag::err_ctor_dtor_returns_void;
3160 D = diag::ext_return_has_void_expr;
3163 ExprResult Result = RetValExp;
3164 Result = IgnoredValueConversions(Result.get());
3165 if (Result.isInvalid())
3167 RetValExp = Result.get();
3168 RetValExp = ImpCastExprToType(RetValExp,
3169 Context.VoidTy, CK_ToVoid).get();
3171 // return of void in constructor/destructor is illegal in C++.
3172 if (D == diag::err_ctor_dtor_returns_void) {
3173 NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
3175 << CurDecl->getDeclName() << isa<CXXDestructorDecl>(CurDecl)
3176 << RetValExp->getSourceRange();
3178 // return (some void expression); is legal in C++.
3179 else if (D != diag::ext_return_has_void_expr ||
3180 !getLangOpts().CPlusPlus) {
3181 NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
3183 int FunctionKind = 0;
3184 if (isa<ObjCMethodDecl>(CurDecl))
3186 else if (isa<CXXConstructorDecl>(CurDecl))
3188 else if (isa<CXXDestructorDecl>(CurDecl))
3192 << CurDecl->getDeclName() << FunctionKind
3193 << RetValExp->getSourceRange();
3198 ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc);
3201 RetValExp = ER.get();
3205 Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, nullptr);
3206 } else if (!RetValExp && !HasDependentReturnType) {
3207 FunctionDecl *FD = getCurFunctionDecl();
3210 if (getLangOpts().CPlusPlus11 && FD && FD->isConstexpr()) {
3211 // C++11 [stmt.return]p2
3212 DiagID = diag::err_constexpr_return_missing_expr;
3213 FD->setInvalidDecl();
3214 } else if (getLangOpts().C99) {
3215 // C99 6.8.6.4p1 (ext_ since GCC warns)
3216 DiagID = diag::ext_return_missing_expr;
3219 DiagID = diag::warn_return_missing_expr;
3223 Diag(ReturnLoc, DiagID) << FD->getIdentifier() << 0/*fn*/;
3225 Diag(ReturnLoc, DiagID) << getCurMethodDecl()->getDeclName() << 1/*meth*/;
3227 Result = new (Context) ReturnStmt(ReturnLoc);
3229 assert(RetValExp || HasDependentReturnType);
3230 const VarDecl *NRVOCandidate = nullptr;
3232 QualType RetType = RelatedRetType.isNull() ? FnRetType : RelatedRetType;
3234 // C99 6.8.6.4p3(136): The return statement is not an assignment. The
3235 // overlap restriction of subclause 6.5.16.1 does not apply to the case of
3238 // In C++ the return statement is handled via a copy initialization,
3239 // the C version of which boils down to CheckSingleAssignmentConstraints.
3241 NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false);
3242 if (!HasDependentReturnType && !RetValExp->isTypeDependent()) {
3243 // we have a non-void function with an expression, continue checking
3244 InitializedEntity Entity = InitializedEntity::InitializeResult(ReturnLoc,
3246 NRVOCandidate != nullptr);
3247 ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRVOCandidate,
3248 RetType, RetValExp);
3249 if (Res.isInvalid()) {
3250 // FIXME: Clean up temporaries here anyway?
3253 RetValExp = Res.getAs<Expr>();
3255 // If we have a related result type, we need to implicitly
3256 // convert back to the formal result type. We can't pretend to
3257 // initialize the result again --- we might end double-retaining
3258 // --- so instead we initialize a notional temporary.
3259 if (!RelatedRetType.isNull()) {
3260 Entity = InitializedEntity::InitializeRelatedResult(getCurMethodDecl(),
3262 Res = PerformCopyInitialization(Entity, ReturnLoc, RetValExp);
3263 if (Res.isInvalid()) {
3264 // FIXME: Clean up temporaries here anyway?
3267 RetValExp = Res.getAs<Expr>();
3270 CheckReturnValExpr(RetValExp, FnRetType, ReturnLoc, isObjCMethod, Attrs,
3271 getCurFunctionDecl());
3275 ExprResult ER = ActOnFinishFullExpr(RetValExp, ReturnLoc);
3278 RetValExp = ER.get();
3280 Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, NRVOCandidate);
3283 // If we need to check for the named return value optimization, save the
3284 // return statement in our scope for later processing.
3285 if (Result->getNRVOCandidate())
3286 FunctionScopes.back()->Returns.push_back(Result);
3292 Sema::ActOnObjCAtCatchStmt(SourceLocation AtLoc,
3293 SourceLocation RParen, Decl *Parm,
3295 VarDecl *Var = cast_or_null<VarDecl>(Parm);
3296 if (Var && Var->isInvalidDecl())
3299 return new (Context) ObjCAtCatchStmt(AtLoc, RParen, Var, Body);
3303 Sema::ActOnObjCAtFinallyStmt(SourceLocation AtLoc, Stmt *Body) {
3304 return new (Context) ObjCAtFinallyStmt(AtLoc, Body);
3308 Sema::ActOnObjCAtTryStmt(SourceLocation AtLoc, Stmt *Try,
3309 MultiStmtArg CatchStmts, Stmt *Finally) {
3310 if (!getLangOpts().ObjCExceptions)
3311 Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@try";
3313 getCurFunction()->setHasBranchProtectedScope();
3314 unsigned NumCatchStmts = CatchStmts.size();
3315 return ObjCAtTryStmt::Create(Context, AtLoc, Try, CatchStmts.data(),
3316 NumCatchStmts, Finally);
3319 StmtResult Sema::BuildObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw) {
3321 ExprResult Result = DefaultLvalueConversion(Throw);
3322 if (Result.isInvalid())
3325 Result = ActOnFinishFullExpr(Result.get());
3326 if (Result.isInvalid())
3328 Throw = Result.get();
3330 QualType ThrowType = Throw->getType();
3331 // Make sure the expression type is an ObjC pointer or "void *".
3332 if (!ThrowType->isDependentType() &&
3333 !ThrowType->isObjCObjectPointerType()) {
3334 const PointerType *PT = ThrowType->getAs<PointerType>();
3335 if (!PT || !PT->getPointeeType()->isVoidType())
3336 return StmtError(Diag(AtLoc, diag::error_objc_throw_expects_object)
3337 << Throw->getType() << Throw->getSourceRange());
3341 return new (Context) ObjCAtThrowStmt(AtLoc, Throw);
3345 Sema::ActOnObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw,
3347 if (!getLangOpts().ObjCExceptions)
3348 Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@throw";
3351 // @throw without an expression designates a rethrow (which must occur
3352 // in the context of an @catch clause).
3353 Scope *AtCatchParent = CurScope;
3354 while (AtCatchParent && !AtCatchParent->isAtCatchScope())
3355 AtCatchParent = AtCatchParent->getParent();
3357 return StmtError(Diag(AtLoc, diag::error_rethrow_used_outside_catch));
3359 return BuildObjCAtThrowStmt(AtLoc, Throw);
3363 Sema::ActOnObjCAtSynchronizedOperand(SourceLocation atLoc, Expr *operand) {
3364 ExprResult result = DefaultLvalueConversion(operand);
3365 if (result.isInvalid())
3367 operand = result.get();
3369 // Make sure the expression type is an ObjC pointer or "void *".
3370 QualType type = operand->getType();
3371 if (!type->isDependentType() &&
3372 !type->isObjCObjectPointerType()) {
3373 const PointerType *pointerType = type->getAs<PointerType>();
3374 if (!pointerType || !pointerType->getPointeeType()->isVoidType()) {
3375 if (getLangOpts().CPlusPlus) {
3376 if (RequireCompleteType(atLoc, type,
3377 diag::err_incomplete_receiver_type))
3378 return Diag(atLoc, diag::error_objc_synchronized_expects_object)
3379 << type << operand->getSourceRange();
3381 ExprResult result = PerformContextuallyConvertToObjCPointer(operand);
3382 if (!result.isUsable())
3383 return Diag(atLoc, diag::error_objc_synchronized_expects_object)
3384 << type << operand->getSourceRange();
3386 operand = result.get();
3388 return Diag(atLoc, diag::error_objc_synchronized_expects_object)
3389 << type << operand->getSourceRange();
3394 // The operand to @synchronized is a full-expression.
3395 return ActOnFinishFullExpr(operand);
3399 Sema::ActOnObjCAtSynchronizedStmt(SourceLocation AtLoc, Expr *SyncExpr,
3401 // We can't jump into or indirect-jump out of a @synchronized block.
3402 getCurFunction()->setHasBranchProtectedScope();
3403 return new (Context) ObjCAtSynchronizedStmt(AtLoc, SyncExpr, SyncBody);
3406 /// ActOnCXXCatchBlock - Takes an exception declaration and a handler block
3407 /// and creates a proper catch handler from them.
3409 Sema::ActOnCXXCatchBlock(SourceLocation CatchLoc, Decl *ExDecl,
3410 Stmt *HandlerBlock) {
3411 // There's nothing to test that ActOnExceptionDecl didn't already test.
3412 return new (Context)
3413 CXXCatchStmt(CatchLoc, cast_or_null<VarDecl>(ExDecl), HandlerBlock);
3417 Sema::ActOnObjCAutoreleasePoolStmt(SourceLocation AtLoc, Stmt *Body) {
3418 getCurFunction()->setHasBranchProtectedScope();
3419 return new (Context) ObjCAutoreleasePoolStmt(AtLoc, Body);
3423 class CatchHandlerType {
3425 unsigned IsPointer : 1;
3427 // This is a special constructor to be used only with DenseMapInfo's
3428 // getEmptyKey() and getTombstoneKey() functions.
3429 friend struct llvm::DenseMapInfo<CatchHandlerType>;
3430 enum Unique { ForDenseMap };
3431 CatchHandlerType(QualType QT, Unique) : QT(QT), IsPointer(false) {}
3434 /// Used when creating a CatchHandlerType from a handler type; will determine
3435 /// whether the type is a pointer or reference and will strip off the the top
3436 /// level pointer and cv-qualifiers.
3437 CatchHandlerType(QualType Q) : QT(Q), IsPointer(false) {
3438 if (QT->isPointerType())
3441 if (IsPointer || QT->isReferenceType())
3442 QT = QT->getPointeeType();
3443 QT = QT.getUnqualifiedType();
3446 /// Used when creating a CatchHandlerType from a base class type; pretends the
3447 /// type passed in had the pointer qualifier, does not need to get an
3448 /// unqualified type.
3449 CatchHandlerType(QualType QT, bool IsPointer)
3450 : QT(QT), IsPointer(IsPointer) {}
3452 QualType underlying() const { return QT; }
3453 bool isPointer() const { return IsPointer; }
3455 friend bool operator==(const CatchHandlerType &LHS,
3456 const CatchHandlerType &RHS) {
3457 // If the pointer qualification does not match, we can return early.
3458 if (LHS.IsPointer != RHS.IsPointer)
3460 // Otherwise, check the underlying type without cv-qualifiers.
3461 return LHS.QT == RHS.QT;
3467 template <> struct DenseMapInfo<CatchHandlerType> {
3468 static CatchHandlerType getEmptyKey() {
3469 return CatchHandlerType(DenseMapInfo<QualType>::getEmptyKey(),
3470 CatchHandlerType::ForDenseMap);
3473 static CatchHandlerType getTombstoneKey() {
3474 return CatchHandlerType(DenseMapInfo<QualType>::getTombstoneKey(),
3475 CatchHandlerType::ForDenseMap);
3478 static unsigned getHashValue(const CatchHandlerType &Base) {
3479 return DenseMapInfo<QualType>::getHashValue(Base.underlying());
3482 static bool isEqual(const CatchHandlerType &LHS,
3483 const CatchHandlerType &RHS) {
3488 // It's OK to treat CatchHandlerType as a POD type.
3489 template <> struct isPodLike<CatchHandlerType> {
3490 static const bool value = true;
3495 class CatchTypePublicBases {
3497 const llvm::DenseMap<CatchHandlerType, CXXCatchStmt *> &TypesToCheck;
3498 const bool CheckAgainstPointer;
3500 CXXCatchStmt *FoundHandler;
3501 CanQualType FoundHandlerType;
3504 CatchTypePublicBases(
3506 const llvm::DenseMap<CatchHandlerType, CXXCatchStmt *> &T, bool C)
3507 : Ctx(Ctx), TypesToCheck(T), CheckAgainstPointer(C),
3508 FoundHandler(nullptr) {}
3510 CXXCatchStmt *getFoundHandler() const { return FoundHandler; }
3511 CanQualType getFoundHandlerType() const { return FoundHandlerType; }
3513 static bool FindPublicBasesOfType(const CXXBaseSpecifier *S, CXXBasePath &,
3515 auto &PBOT = *reinterpret_cast<CatchTypePublicBases *>(User);
3516 if (S->getAccessSpecifier() == AccessSpecifier::AS_public) {
3517 CatchHandlerType Check(S->getType(), PBOT.CheckAgainstPointer);
3518 auto M = PBOT.TypesToCheck;
3519 auto I = M.find(Check);
3521 PBOT.FoundHandler = I->second;
3522 PBOT.FoundHandlerType = PBOT.Ctx.getCanonicalType(S->getType());
3531 /// ActOnCXXTryBlock - Takes a try compound-statement and a number of
3532 /// handlers and creates a try statement from them.
3533 StmtResult Sema::ActOnCXXTryBlock(SourceLocation TryLoc, Stmt *TryBlock,
3534 ArrayRef<Stmt *> Handlers) {
3535 // Don't report an error if 'try' is used in system headers.
3536 if (!getLangOpts().CXXExceptions &&
3537 !getSourceManager().isInSystemHeader(TryLoc))
3538 Diag(TryLoc, diag::err_exceptions_disabled) << "try";
3540 if (getCurScope() && getCurScope()->isOpenMPSimdDirectiveScope())
3541 Diag(TryLoc, diag::err_omp_simd_region_cannot_use_stmt) << "try";
3543 sema::FunctionScopeInfo *FSI = getCurFunction();
3545 // C++ try is incompatible with SEH __try.
3546 if (!getLangOpts().Borland && FSI->FirstSEHTryLoc.isValid()) {
3547 Diag(TryLoc, diag::err_mixing_cxx_try_seh_try);
3548 Diag(FSI->FirstSEHTryLoc, diag::note_conflicting_try_here) << "'__try'";
3551 const unsigned NumHandlers = Handlers.size();
3552 assert(!Handlers.empty() &&
3553 "The parser shouldn't call this if there are no handlers.");
3555 llvm::DenseMap<CatchHandlerType, CXXCatchStmt *> HandledTypes;
3556 for (unsigned i = 0; i < NumHandlers; ++i) {
3557 CXXCatchStmt *H = cast<CXXCatchStmt>(Handlers[i]);
3559 // Diagnose when the handler is a catch-all handler, but it isn't the last
3560 // handler for the try block. [except.handle]p5. Also, skip exception
3561 // declarations that are invalid, since we can't usefully report on them.
3562 if (!H->getExceptionDecl()) {
3563 if (i < NumHandlers - 1)
3564 return StmtError(Diag(H->getLocStart(), diag::err_early_catch_all));
3566 } else if (H->getExceptionDecl()->isInvalidDecl())
3569 // Walk the type hierarchy to diagnose when this type has already been
3570 // handled (duplication), or cannot be handled (derivation inversion). We
3571 // ignore top-level cv-qualifiers, per [except.handle]p3
3572 CatchHandlerType HandlerCHT =
3573 (QualType)Context.getCanonicalType(H->getCaughtType());
3575 // We can ignore whether the type is a reference or a pointer; we need the
3576 // underlying declaration type in order to get at the underlying record
3577 // decl, if there is one.
3578 QualType Underlying = HandlerCHT.underlying();
3579 if (auto *RD = Underlying->getAsCXXRecordDecl()) {
3580 if (!RD->hasDefinition())
3582 // Check that none of the public, unambiguous base classes are in the
3583 // map ([except.handle]p1). Give the base classes the same pointer
3584 // qualification as the original type we are basing off of. This allows
3585 // comparison against the handler type using the same top-level pointer
3586 // as the original type.
3588 Paths.setOrigin(RD);
3589 CatchTypePublicBases CTPB(Context, HandledTypes, HandlerCHT.isPointer());
3590 if (RD->lookupInBases(CatchTypePublicBases::FindPublicBasesOfType, &CTPB,
3592 const CXXCatchStmt *Problem = CTPB.getFoundHandler();
3593 if (!Paths.isAmbiguous(CTPB.getFoundHandlerType())) {
3594 Diag(H->getExceptionDecl()->getTypeSpecStartLoc(),
3595 diag::warn_exception_caught_by_earlier_handler)
3596 << H->getCaughtType();
3597 Diag(Problem->getExceptionDecl()->getTypeSpecStartLoc(),
3598 diag::note_previous_exception_handler)
3599 << Problem->getCaughtType();
3604 // Add the type the list of ones we have handled; diagnose if we've already
3606 auto R = HandledTypes.insert(std::make_pair(H->getCaughtType(), H));
3608 const CXXCatchStmt *Problem = R.first->second;
3609 Diag(H->getExceptionDecl()->getTypeSpecStartLoc(),
3610 diag::warn_exception_caught_by_earlier_handler)
3611 << H->getCaughtType();
3612 Diag(Problem->getExceptionDecl()->getTypeSpecStartLoc(),
3613 diag::note_previous_exception_handler)
3614 << Problem->getCaughtType();
3618 FSI->setHasCXXTry(TryLoc);
3620 return CXXTryStmt::Create(Context, TryLoc, TryBlock, Handlers);
3623 StmtResult Sema::ActOnSEHTryBlock(bool IsCXXTry, SourceLocation TryLoc,
3624 Stmt *TryBlock, Stmt *Handler) {
3625 assert(TryBlock && Handler);
3627 sema::FunctionScopeInfo *FSI = getCurFunction();
3629 // SEH __try is incompatible with C++ try. Borland appears to support this,
3631 if (!getLangOpts().Borland) {
3632 if (FSI->FirstCXXTryLoc.isValid()) {
3633 Diag(TryLoc, diag::err_mixing_cxx_try_seh_try);
3634 Diag(FSI->FirstCXXTryLoc, diag::note_conflicting_try_here) << "'try'";
3638 FSI->setHasSEHTry(TryLoc);
3640 // Reject __try in Obj-C methods, blocks, and captured decls, since we don't
3641 // track if they use SEH.
3642 DeclContext *DC = CurContext;
3643 while (DC && !DC->isFunctionOrMethod())
3644 DC = DC->getParent();
3645 FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(DC);
3647 FD->setUsesSEHTry(true);
3649 Diag(TryLoc, diag::err_seh_try_outside_functions);
3651 return SEHTryStmt::Create(Context, IsCXXTry, TryLoc, TryBlock, Handler);
3655 Sema::ActOnSEHExceptBlock(SourceLocation Loc,
3658 assert(FilterExpr && Block);
3660 if(!FilterExpr->getType()->isIntegerType()) {
3661 return StmtError(Diag(FilterExpr->getExprLoc(),
3662 diag::err_filter_expression_integral)
3663 << FilterExpr->getType());
3666 return SEHExceptStmt::Create(Context,Loc,FilterExpr,Block);
3669 void Sema::ActOnStartSEHFinallyBlock() {
3670 CurrentSEHFinally.push_back(CurScope);
3673 void Sema::ActOnAbortSEHFinallyBlock() {
3674 CurrentSEHFinally.pop_back();
3677 StmtResult Sema::ActOnFinishSEHFinallyBlock(SourceLocation Loc, Stmt *Block) {
3679 CurrentSEHFinally.pop_back();
3680 return SEHFinallyStmt::Create(Context, Loc, Block);
3684 Sema::ActOnSEHLeaveStmt(SourceLocation Loc, Scope *CurScope) {
3685 Scope *SEHTryParent = CurScope;
3686 while (SEHTryParent && !SEHTryParent->isSEHTryScope())
3687 SEHTryParent = SEHTryParent->getParent();
3689 return StmtError(Diag(Loc, diag::err_ms___leave_not_in___try));
3690 CheckJumpOutOfSEHFinally(*this, Loc, *SEHTryParent);
3692 return new (Context) SEHLeaveStmt(Loc);
3695 StmtResult Sema::BuildMSDependentExistsStmt(SourceLocation KeywordLoc,
3697 NestedNameSpecifierLoc QualifierLoc,
3698 DeclarationNameInfo NameInfo,
3701 return new (Context) MSDependentExistsStmt(KeywordLoc, IsIfExists,
3702 QualifierLoc, NameInfo,
3703 cast<CompoundStmt>(Nested));
3707 StmtResult Sema::ActOnMSDependentExistsStmt(SourceLocation KeywordLoc,
3710 UnqualifiedId &Name,
3712 return BuildMSDependentExistsStmt(KeywordLoc, IsIfExists,
3713 SS.getWithLocInContext(Context),
3714 GetNameFromUnqualifiedId(Name),
3719 Sema::CreateCapturedStmtRecordDecl(CapturedDecl *&CD, SourceLocation Loc,
3720 unsigned NumParams) {
3721 DeclContext *DC = CurContext;
3722 while (!(DC->isFunctionOrMethod() || DC->isRecord() || DC->isFileContext()))
3723 DC = DC->getParent();
3725 RecordDecl *RD = nullptr;
3726 if (getLangOpts().CPlusPlus)
3727 RD = CXXRecordDecl::Create(Context, TTK_Struct, DC, Loc, Loc,
3730 RD = RecordDecl::Create(Context, TTK_Struct, DC, Loc, Loc, /*Id=*/nullptr);
3732 RD->setCapturedRecord();
3735 RD->startDefinition();
3737 assert(NumParams > 0 && "CapturedStmt requires context parameter");
3738 CD = CapturedDecl::Create(Context, CurContext, NumParams);
3743 static void buildCapturedStmtCaptureList(
3744 SmallVectorImpl<CapturedStmt::Capture> &Captures,
3745 SmallVectorImpl<Expr *> &CaptureInits,
3746 ArrayRef<CapturingScopeInfo::Capture> Candidates) {
3748 typedef ArrayRef<CapturingScopeInfo::Capture>::const_iterator CaptureIter;
3749 for (CaptureIter Cap = Candidates.begin(); Cap != Candidates.end(); ++Cap) {
3751 if (Cap->isThisCapture()) {
3752 Captures.push_back(CapturedStmt::Capture(Cap->getLocation(),
3753 CapturedStmt::VCK_This));
3754 CaptureInits.push_back(Cap->getInitExpr());
3756 } else if (Cap->isVLATypeCapture()) {
3758 CapturedStmt::Capture(Cap->getLocation(), CapturedStmt::VCK_VLAType));
3759 CaptureInits.push_back(nullptr);
3763 assert(Cap->isReferenceCapture() &&
3764 "non-reference capture not yet implemented");
3766 Captures.push_back(CapturedStmt::Capture(Cap->getLocation(),
3767 CapturedStmt::VCK_ByRef,
3768 Cap->getVariable()));
3769 CaptureInits.push_back(Cap->getInitExpr());
3773 void Sema::ActOnCapturedRegionStart(SourceLocation Loc, Scope *CurScope,
3774 CapturedRegionKind Kind,
3775 unsigned NumParams) {
3776 CapturedDecl *CD = nullptr;
3777 RecordDecl *RD = CreateCapturedStmtRecordDecl(CD, Loc, NumParams);
3779 // Build the context parameter
3780 DeclContext *DC = CapturedDecl::castToDeclContext(CD);
3781 IdentifierInfo *ParamName = &Context.Idents.get("__context");
3782 QualType ParamType = Context.getPointerType(Context.getTagDeclType(RD));
3783 ImplicitParamDecl *Param
3784 = ImplicitParamDecl::Create(Context, DC, Loc, ParamName, ParamType);
3787 CD->setContextParam(0, Param);
3789 // Enter the capturing scope for this captured region.
3790 PushCapturedRegionScope(CurScope, CD, RD, Kind);
3793 PushDeclContext(CurScope, CD);
3797 PushExpressionEvaluationContext(PotentiallyEvaluated);
3800 void Sema::ActOnCapturedRegionStart(SourceLocation Loc, Scope *CurScope,
3801 CapturedRegionKind Kind,
3802 ArrayRef<CapturedParamNameType> Params) {
3803 CapturedDecl *CD = nullptr;
3804 RecordDecl *RD = CreateCapturedStmtRecordDecl(CD, Loc, Params.size());
3806 // Build the context parameter
3807 DeclContext *DC = CapturedDecl::castToDeclContext(CD);
3808 bool ContextIsFound = false;
3809 unsigned ParamNum = 0;
3810 for (ArrayRef<CapturedParamNameType>::iterator I = Params.begin(),
3812 I != E; ++I, ++ParamNum) {
3813 if (I->second.isNull()) {
3814 assert(!ContextIsFound &&
3815 "null type has been found already for '__context' parameter");
3816 IdentifierInfo *ParamName = &Context.Idents.get("__context");
3817 QualType ParamType = Context.getPointerType(Context.getTagDeclType(RD));
3818 ImplicitParamDecl *Param
3819 = ImplicitParamDecl::Create(Context, DC, Loc, ParamName, ParamType);
3821 CD->setContextParam(ParamNum, Param);
3822 ContextIsFound = true;
3824 IdentifierInfo *ParamName = &Context.Idents.get(I->first);
3825 ImplicitParamDecl *Param
3826 = ImplicitParamDecl::Create(Context, DC, Loc, ParamName, I->second);
3828 CD->setParam(ParamNum, Param);
3831 assert(ContextIsFound && "no null type for '__context' parameter");
3832 if (!ContextIsFound) {
3833 // Add __context implicitly if it is not specified.
3834 IdentifierInfo *ParamName = &Context.Idents.get("__context");
3835 QualType ParamType = Context.getPointerType(Context.getTagDeclType(RD));
3836 ImplicitParamDecl *Param =
3837 ImplicitParamDecl::Create(Context, DC, Loc, ParamName, ParamType);
3839 CD->setContextParam(ParamNum, Param);
3841 // Enter the capturing scope for this captured region.
3842 PushCapturedRegionScope(CurScope, CD, RD, Kind);
3845 PushDeclContext(CurScope, CD);
3849 PushExpressionEvaluationContext(PotentiallyEvaluated);
3852 void Sema::ActOnCapturedRegionError() {
3853 DiscardCleanupsInEvaluationContext();
3854 PopExpressionEvaluationContext();
3856 CapturedRegionScopeInfo *RSI = getCurCapturedRegion();
3857 RecordDecl *Record = RSI->TheRecordDecl;
3858 Record->setInvalidDecl();
3860 SmallVector<Decl*, 4> Fields(Record->fields());
3861 ActOnFields(/*Scope=*/nullptr, Record->getLocation(), Record, Fields,
3862 SourceLocation(), SourceLocation(), /*AttributeList=*/nullptr);
3865 PopFunctionScopeInfo();
3868 StmtResult Sema::ActOnCapturedRegionEnd(Stmt *S) {
3869 CapturedRegionScopeInfo *RSI = getCurCapturedRegion();
3871 SmallVector<CapturedStmt::Capture, 4> Captures;
3872 SmallVector<Expr *, 4> CaptureInits;
3873 buildCapturedStmtCaptureList(Captures, CaptureInits, RSI->Captures);
3875 CapturedDecl *CD = RSI->TheCapturedDecl;
3876 RecordDecl *RD = RSI->TheRecordDecl;
3878 CapturedStmt *Res = CapturedStmt::Create(getASTContext(), S,
3879 RSI->CapRegionKind, Captures,
3880 CaptureInits, CD, RD);
3882 CD->setBody(Res->getCapturedStmt());
3883 RD->completeDefinition();
3885 DiscardCleanupsInEvaluationContext();
3886 PopExpressionEvaluationContext();
3889 PopFunctionScopeInfo();