[Bugpoint] Erase comdat annotations after removing a global's initializer.

Summary:
This is necessary to keep the verifier happy after bugpoint removes an
initializer from a global variable with a comdat annotation, because
globals without initializers may not have comdats.

Reviewers: majnemer, rnk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D21274

llvm-svn: 272854

2 files changed, 4 insertions, 0 deletions

diff --git a/llvm/tools/bugpoint/CrashDebugger.cpp b/llvm/tools/bugpoint/CrashDebugger.cpp
index b161d88882a..02e488ed3da 100644
--- a/llvm/tools/bugpoint/CrashDebugger.cpp
+++ b/llvm/tools/bugpoint/CrashDebugger.cpp
@@ -164,6 +164,7 @@ ReduceCrashingGlobalVariables::TestGlobalVariables(
     if (I.hasInitializer() && !GVSet.count(&I)) {
       DeleteGlobalInitializer(&I);
       I.setLinkage(GlobalValue::ExternalLinkage);
+      I.setComdat(nullptr);
     }
 
   // Try running the hacked up program...
@@ -668,6 +669,7 @@ static bool DebugACrash(BugDriver &BD,
       if (I->hasInitializer()) {
         DeleteGlobalInitializer(&*I);
         I->setLinkage(GlobalValue::ExternalLinkage);
+        I->setComdat(nullptr);
         DeletedInit = true;
       }
 
diff --git a/llvm/tools/bugpoint/ExtractFunction.cpp b/llvm/tools/bugpoint/ExtractFunction.cpp
index fe0ab69dc16..ae202c3f77e 100644
--- a/llvm/tools/bugpoint/ExtractFunction.cpp
+++ b/llvm/tools/bugpoint/ExtractFunction.cpp
@@ -215,6 +215,8 @@ void llvm::DeleteGlobalInitializer(GlobalVariable *GV) {
 //
 void llvm::DeleteFunctionBody(Function *F) {
   eliminateAliases(F);
+  // Function declarations can't have comdats.
+  F->setComdat(nullptr);
 
   // delete the body of the function...
   F->deleteBody();