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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@712 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/AsmParser/llvmAsmParser.y b/lib/AsmParser/llvmAsmParser.y
index 6edd2797c2aa8c8a56bbd239a00879a47bc1d66d..1ee6d50b567aa3c1d3bf0f45f1188effb0b7de69 100644 (file)
--- a/lib/AsmParser/llvmAsmParser.y
+++ b/lib/AsmParser/llvmAsmParser.y
@@ -456,6 +456,12 @@ static bool setValueName(Value *V, char *NameStr) {
       // cerr << "Type: " << Ty->getDescription() << " != "
       //      << cast<const Type>(V)->getDescription() << "!\n";
     } else if (GlobalVariable *EGV = dyn_cast<GlobalVariable>(Existing)) {
+      // We are allowed to redefine a global variable in two circumstances:
+      // 1. If at least one of the globals is uninitialized or 
+      // 2. If both initializers have the same value.
+      //
+      // This can only be done if the const'ness of the vars is the same.
+      //
       if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V)) {
         if (EGV->isConstant() == GV->isConstant() &&
             (!EGV->hasInitializer() || !GV->hasInitializer() ||