Introducing external weak linkage. Darwin codegen should be added later.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32052 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 2 insertions, 5 deletions

diff --git a/lib/VMCore/ConstantFold.cpp b/lib/VMCore/ConstantFold.cpp
index 9974071385..fd6ad108a9 100644
--- a/lib/VMCore/ConstantFold.cpp
+++ b/lib/VMCore/ConstantFold.cpp
@@ -894,11 +894,8 @@ Constant *llvm::ConstantFoldCastInstruction(unsigned opc, const Constant *V,
 
   case Instruction::PtrToInt:
     // Cast of a global address to boolean is always true.
-    if (isa<GlobalValue>(V)) {
-      if (DestTy == Type::BoolTy)
-        // FIXME: When we support 'external weak' references, we have to 
-        // prevent this transformation from happening.  This code will need 
-        // to be updated to ignore external weak symbols when we support it.
+    if (const GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
+      if (DestTy == Type::BoolTy && !GV->hasExternalWeakLinkage())
         return ConstantBool::getTrue();
     }
     break;