PR18217: Rewrite JumpDiagnostics' handling of temporaries, to correctly handle
declarations that might lifetime-extend multiple temporaries. In passing, fix a
crasher (PR18217) if an initializer was dependent and exactly the wrong shape,
and remove a bogus function (Expr::findMaterializedTemporary) now its last use
is gone.
llvm-svn: 197103
diff --git a/clang/lib/Sema/JumpDiagnostics.cpp b/clang/lib/Sema/JumpDiagnostics.cpp
index b58bc51..a07f442 100644
--- a/clang/lib/Sema/JumpDiagnostics.cpp
+++ b/clang/lib/Sema/JumpDiagnostics.cpp
@@ -121,9 +121,11 @@
/// GetDiagForGotoScopeDecl - If this decl induces a new goto scope, return a
/// diagnostic that should be emitted if control goes over it. If not, return 0.
-static ScopePair GetDiagForGotoScopeDecl(ASTContext &Context, const Decl *D) {
+static ScopePair GetDiagForGotoScopeDecl(Sema &S, const Decl *D) {
if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
unsigned InDiag = 0;
+ unsigned OutDiag = 0;
+
if (VD->getType()->isVariablyModifiedType())
InDiag = diag::note_protected_by_vla;
@@ -135,21 +137,24 @@
return ScopePair(diag::note_protected_by_cleanup,
diag::note_exits_cleanup);
- if (Context.getLangOpts().ObjCAutoRefCount && VD->hasLocalStorage()) {
- switch (VD->getType().getObjCLifetime()) {
- case Qualifiers::OCL_None:
- case Qualifiers::OCL_ExplicitNone:
- case Qualifiers::OCL_Autoreleasing:
- break;
-
- case Qualifiers::OCL_Strong:
- case Qualifiers::OCL_Weak:
+ if (VD->hasLocalStorage()) {
+ switch (VD->getType().isDestructedType()) {
+ case QualType::DK_objc_strong_lifetime:
+ case QualType::DK_objc_weak_lifetime:
return ScopePair(diag::note_protected_by_objc_ownership,
diag::note_exits_objc_ownership);
+
+ case QualType::DK_cxx_destructor:
+ OutDiag = diag::note_exits_dtor;
+ break;
+
+ case QualType::DK_none:
+ break;
}
}
- if (Context.getLangOpts().CPlusPlus && VD->hasLocalStorage()) {
+ const Expr *Init = VD->getInit();
+ if (S.Context.getLangOpts().CPlusPlus && VD->hasLocalStorage() && Init) {
// C++11 [stmt.dcl]p3:
// A program that jumps from a point where a variable with automatic
// storage duration is not in scope to a point where it is in scope
@@ -164,68 +169,34 @@
// where it is in scope is ill-formed unless the variable has
// POD type and is declared without an initializer.
- const Expr *Init = VD->getInit();
- if (!Init)
- return ScopePair(InDiag, 0);
+ InDiag = diag::note_protected_by_variable_init;
- const ExprWithCleanups *EWC = dyn_cast<ExprWithCleanups>(Init);
- if (EWC)
- Init = EWC->getSubExpr();
-
- const MaterializeTemporaryExpr *M = NULL;
- Init = Init->findMaterializedTemporary(M);
-
- SmallVector<const Expr *, 2> CommaLHSs;
- SmallVector<SubobjectAdjustment, 2> Adjustments;
- Init = Init->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments);
-
- QualType QT = Init->getType();
- if (QT.isNull())
- return ScopePair(diag::note_protected_by_variable_init, 0);
-
- const Type *T = QT.getTypePtr();
- if (T->isArrayType())
- T = T->getBaseElementTypeUnsafe();
-
- const CXXRecordDecl *Record = T->getAsCXXRecordDecl();
- if (!Record)
- return ScopePair(diag::note_protected_by_variable_init, 0);
-
- // If we need to call a non-trivial destructor for this variable,
- // record an out diagnostic.
- unsigned OutDiag = 0;
- if (!Init->isGLValue() && !Record->hasTrivialDestructor())
- OutDiag = diag::note_exits_dtor;
-
- if (const CXXConstructExpr *cce = dyn_cast<CXXConstructExpr>(Init)) {
- const CXXConstructorDecl *ctor = cce->getConstructor();
- // For a variable declared without an initializer, we will have
- // call-style initialization and the initializer will be the
- // CXXConstructExpr with no intervening nodes.
- if (ctor->isTrivial() && ctor->isDefaultConstructor() &&
- VD->getInit() == Init && VD->getInitStyle() == VarDecl::CallInit) {
+ // For a variable of (array of) class type declared without an
+ // initializer, we will have call-style initialization and the initializer
+ // will be the CXXConstructExpr with no intervening nodes.
+ if (const CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init)) {
+ const CXXConstructorDecl *Ctor = CCE->getConstructor();
+ if (Ctor->isTrivial() && Ctor->isDefaultConstructor() &&
+ VD->getInitStyle() == VarDecl::CallInit) {
if (OutDiag)
InDiag = diag::note_protected_by_variable_nontriv_destructor;
- else if (!Record->isPOD())
+ else if (!Ctor->getParent()->isPOD())
InDiag = diag::note_protected_by_variable_non_pod;
- return ScopePair(InDiag, OutDiag);
+ else
+ InDiag = 0;
}
}
-
- return ScopePair(diag::note_protected_by_variable_init, OutDiag);
}
- return ScopePair(InDiag, 0);
+ return ScopePair(InDiag, OutDiag);
}
- if (const TypedefDecl *TD = dyn_cast<TypedefDecl>(D)) {
+ if (const TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(D)) {
if (TD->getUnderlyingType()->isVariablyModifiedType())
- return ScopePair(diag::note_protected_by_vla_typedef, 0);
- }
-
- if (const TypeAliasDecl *TD = dyn_cast<TypeAliasDecl>(D)) {
- if (TD->getUnderlyingType()->isVariablyModifiedType())
- return ScopePair(diag::note_protected_by_vla_type_alias, 0);
+ return ScopePair(isa<TypedefDecl>(TD)
+ ? diag::note_protected_by_vla_typedef
+ : diag::note_protected_by_vla_type_alias,
+ 0);
}
return ScopePair(0U, 0U);
@@ -234,7 +205,7 @@
/// \brief Build scope information for a declaration that is part of a DeclStmt.
void JumpScopeChecker::BuildScopeInformation(Decl *D, unsigned &ParentScope) {
// If this decl causes a new scope, push and switch to it.
- std::pair<unsigned,unsigned> Diags = GetDiagForGotoScopeDecl(S.Context, D);
+ std::pair<unsigned,unsigned> Diags = GetDiagForGotoScopeDecl(S, D);
if (Diags.first || Diags.second) {
Scopes.push_back(GotoScope(ParentScope, Diags.first, Diags.second,
D->getLocation()));
@@ -481,7 +452,26 @@
}
}
}
-
+
+ // Disallow jumps out of scopes containing temporaries lifetime-extended to
+ // automatic storage duration.
+ if (MaterializeTemporaryExpr *MTE =
+ dyn_cast<MaterializeTemporaryExpr>(SubStmt)) {
+ if (MTE->getStorageDuration() == SD_Automatic) {
+ SmallVector<const Expr *, 4> CommaLHS;
+ SmallVector<SubobjectAdjustment, 4> Adjustments;
+ const Expr *ExtendedObject =
+ MTE->GetTemporaryExpr()->skipRValueSubobjectAdjustments(
+ CommaLHS, Adjustments);
+ if (ExtendedObject->getType().isDestructedType()) {
+ Scopes.push_back(GotoScope(ParentScope, 0,
+ diag::note_exits_temporary_dtor,
+ ExtendedObject->getExprLoc()));
+ ParentScope = Scopes.size()-1;
+ }
+ }
+ }
+
// Recursively walk the AST.
BuildScopeInformation(SubStmt, ParentScope);
}