Fix mangling for block literals.

Blocks, like lambdas, can be written in contexts which are required to be
treated as the same under ODR.  Unlike lambdas, it isn't possible to actually
take the address of a block, so the mangling of the block itself doesn't
matter. However, objects like static variables inside a block do need to
be mangled in a consistent way.

There are basically three components here. One, block literals need a
consistent numbering.  Two, objects/types inside a block literal need
to be mangled using it.  Three, objects/types inside a block literal need
to have their linkage computed correctly.

llvm-svn: 185372

1 files changed, 3 insertions, 4 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 3298d5a..cfb9e78 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -1797,7 +1797,7 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) {
 
   // Set the llvm linkage type as appropriate.
   llvm::GlobalValue::LinkageTypes Linkage = 
-    GetLLVMLinkageVarDefinition(D, GV);
+    GetLLVMLinkageVarDefinition(D, GV->isConstant());
   GV->setLinkage(Linkage);
   if (Linkage == llvm::GlobalVariable::CommonLinkage)
     // common vars aren't constant even if declared const.
@@ -1828,8 +1828,7 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) {
 }
 
 llvm::GlobalValue::LinkageTypes
-CodeGenModule::GetLLVMLinkageVarDefinition(const VarDecl *D,
-                                           llvm::GlobalVariable *GV) {
+CodeGenModule::GetLLVMLinkageVarDefinition(const VarDecl *D, bool isConstant) {
   GVALinkage Linkage = getContext().GetGVALinkageForVariable(D);
   if (Linkage == GVA_Internal)
     return llvm::Function::InternalLinkage;
@@ -1844,7 +1843,7 @@ CodeGenModule::GetLLVMLinkageVarDefinition(const VarDecl *D,
     // http://msdn.microsoft.com/en-us/library/5tkz6s71.aspx
     return llvm::GlobalVariable::WeakODRLinkage;
   } else if (D->hasAttr<WeakAttr>()) {
-    if (GV->isConstant())
+    if (isConstant)
       return llvm::GlobalVariable::WeakODRLinkage;
     else
       return llvm::GlobalVariable::WeakAnyLinkage;