vendor/clang/clang-trunk-r291476

1 files changed, 47 insertions, 5 deletions

diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index a650621b573a..a70e16cce18c 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -5395,14 +5395,32 @@ static void ReferenceDllExportedMethods(Sema &S, CXXRecordDecl *Class) {
   }
 }
 
-static void checkForMultipleExportedDefaultConstructors(Sema &S, CXXRecordDecl *Class) {
+static void checkForMultipleExportedDefaultConstructors(Sema &S,
+                                                        CXXRecordDecl *Class) {
+  // Only the MS ABI has default constructor closures, so we don't need to do
+  // this semantic checking anywhere else.
+  if (!S.Context.getTargetInfo().getCXXABI().isMicrosoft())
+    return;
+
   CXXConstructorDecl *LastExportedDefaultCtor = nullptr;
   for (Decl *Member : Class->decls()) {
     // Look for exported default constructors.
     auto *CD = dyn_cast<CXXConstructorDecl>(Member);
-    if (!CD || !CD->isDefaultConstructor() || !CD->hasAttr<DLLExportAttr>())
+    if (!CD || !CD->isDefaultConstructor())
+      continue;
+    auto *Attr = CD->getAttr<DLLExportAttr>();
+    if (!Attr)
       continue;
 
+    // If the class is non-dependent, mark the default arguments as ODR-used so
+    // that we can properly codegen the constructor closure.
+    if (!Class->isDependentContext()) {
+      for (ParmVarDecl *PD : CD->parameters()) {
+        (void)S.CheckCXXDefaultArgExpr(Attr->getLocation(), CD, PD);
+        S.DiscardCleanupsInEvaluationContext();
+      }
+    }
+
     if (LastExportedDefaultCtor) {
       S.Diag(LastExportedDefaultCtor->getLocation(),
              diag::err_attribute_dll_ambiguous_default_ctor)
@@ -9135,6 +9153,16 @@ NamedDecl *Sema::BuildUsingDeclaration(Scope *S, AccessSpecifier AS,
   // invalid).
   if (R.empty() &&
       NameInfo.getName().getNameKind() != DeclarationName::CXXConstructorName) {
+    // HACK: Work around a bug in libstdc++'s detection of ::gets. Sometimes
+    // it will believe that glibc provides a ::gets in cases where it does not,
+    // and will try to pull it into namespace std with a using-declaration.
+    // Just ignore the using-declaration in that case.
+    auto *II = NameInfo.getName().getAsIdentifierInfo();
+    if (getLangOpts().CPlusPlus14 && II && II->isStr("gets") &&
+        CurContext->isStdNamespace() &&
+        isa<TranslationUnitDecl>(LookupContext) &&
+        getSourceManager().isInSystemHeader(UsingLoc))
+      return nullptr;
     if (TypoCorrection Corrected = CorrectTypo(
             R.getLookupNameInfo(), R.getLookupKind(), S, &SS,
             llvm::make_unique<UsingValidatorCCC>(
@@ -9828,9 +9856,14 @@ Sema::ComputeDefaultedDefaultCtorExceptionSpec(SourceLocation Loc,
   }
 
   // Field constructors.
-  for (const auto *F : ClassDecl->fields()) {
+  for (auto *F : ClassDecl->fields()) {
     if (F->hasInClassInitializer()) {
-      if (Expr *E = F->getInClassInitializer())
+      Expr *E = F->getInClassInitializer();
+      if (!E)
+        // FIXME: It's a little wasteful to build and throw away a
+        // CXXDefaultInitExpr here.
+        E = BuildCXXDefaultInitExpr(Loc, F).get();
+      if (E)
         ExceptSpec.CalledExpr(E);
     } else if (const RecordType *RecordTy
               = Context.getBaseElementType(F->getType())->getAs<RecordType>()) {
@@ -12291,6 +12324,10 @@ ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
   if (Field->getInClassInitializer())
     return CXXDefaultInitExpr::Create(Context, Loc, Field);
 
+  // If we might have already tried and failed to instantiate, don't try again.
+  if (Field->isInvalidDecl())
+    return ExprError();
+
   // Maybe we haven't instantiated the in-class initializer. Go check the
   // pattern FieldDecl to see if it has one.
   CXXRecordDecl *ParentRD = cast<CXXRecordDecl>(Field->getParent());
@@ -12320,8 +12357,11 @@ ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
     }
 
     if (InstantiateInClassInitializer(Loc, Field, Pattern,
-                                      getTemplateInstantiationArgs(Field)))
+                                      getTemplateInstantiationArgs(Field))) {
+      // Don't diagnose this again.
+      Field->setInvalidDecl();
       return ExprError();
+    }
     return CXXDefaultInitExpr::Create(Context, Loc, Field);
   }
 
@@ -12344,6 +12384,8 @@ ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
       << OutermostClass << Field;
   Diag(Field->getLocEnd(), diag::note_in_class_initializer_not_yet_parsed);
 
+  // Don't diagnose this again.
+  Field->setInvalidDecl();
   return ExprError();
 }