Deal with a horrible C++11 special case. If a non-literal type has a constexpr

constructor, and that constructor is used to initialize an object of static
storage duration such that all members and bases are initialized by constant
expressions, constant initialization is performed. In this case, the object
can still have a non-trivial destructor, and if it does, we must emit a dynamic
initializer which performs no initialization and instead simply registers that
destructor.

llvm-svn: 150419

1 files changed, 11 insertions, 7 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index fde217efecf..2ebea592641 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -1359,7 +1359,9 @@ CharUnits CodeGenModule::GetTargetTypeStoreSize(llvm::Type *Ty) const {
 void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) {
   llvm::Constant *Init = 0;
   QualType ASTTy = D->getType();
-  bool NonConstInit = false;
+  CXXRecordDecl *RD = ASTTy->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
+  bool NeedsGlobalCtor = false;
+  bool NeedsGlobalDtor = RD && !RD->hasTrivialDestructor();
 
   const VarDecl *InitDecl;
   const Expr *InitExpr = D->getAnyInitializer(InitDecl);
@@ -1385,15 +1387,16 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) {
 
       if (getLangOptions().CPlusPlus) {
         Init = EmitNullConstant(T);
-        NonConstInit = true;
+        NeedsGlobalCtor = true;
       } else {
         ErrorUnsupported(D, "static initializer");
         Init = llvm::UndefValue::get(getTypes().ConvertType(T));
       }
     } else {
       // We don't need an initializer, so remove the entry for the delayed
-      // initializer position (just in case this entry was delayed).
-      if (getLangOptions().CPlusPlus)
+      // initializer position (just in case this entry was delayed) if we
+      // also don't need to register a destructor.
+      if (getLangOptions().CPlusPlus && !NeedsGlobalDtor)
         DelayedCXXInitPosition.erase(D);
     }
   }
@@ -1448,7 +1451,8 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) {
 
   // If it is safe to mark the global 'constant', do so now.
   GV->setConstant(false);
-  if (!NonConstInit && DeclIsConstantGlobal(Context, D, true))
+  if (!NeedsGlobalCtor && !NeedsGlobalDtor &&
+      DeclIsConstantGlobal(Context, D, true))
     GV->setConstant(true);
 
   GV->setAlignment(getContext().getDeclAlign(D).getQuantity());
@@ -1464,8 +1468,8 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) {
   SetCommonAttributes(D, GV);
 
   // Emit the initializer function if necessary.
-  if (NonConstInit)
-    EmitCXXGlobalVarDeclInitFunc(D, GV);
+  if (NeedsGlobalCtor || NeedsGlobalDtor)
+    EmitCXXGlobalVarDeclInitFunc(D, GV, NeedsGlobalCtor);
 
   // Emit global variable debug information.
   if (CGDebugInfo *DI = getModuleDebugInfo())