1 files changed, 21 insertions, 13 deletions

diff --git a/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index b034ccc46933..7eea44d6aca0 100644
--- a/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -613,7 +613,15 @@ public:
                                   bool UseGlobalsGC = true)
       : ModulePass(ID), CompileKernel(CompileKernel || ClEnableKasan),
         Recover(Recover || ClRecover),
-        UseGlobalsGC(UseGlobalsGC && ClUseGlobalsGC) {}
+        UseGlobalsGC(UseGlobalsGC && ClUseGlobalsGC),
+        // Not a typo: ClWithComdat is almost completely pointless without
+        // ClUseGlobalsGC (because then it only works on modules without
+        // globals, which are rare); it is a prerequisite for ClUseGlobalsGC;
+        // and both suffer from gold PR19002 for which UseGlobalsGC constructor
+        // argument is designed as workaround. Therefore, disable both
+        // ClWithComdat and ClUseGlobalsGC unless the frontend says it's ok to
+        // do globals-gc.
+        UseCtorComdat(UseGlobalsGC && ClWithComdat) {}
   bool runOnModule(Module &M) override;
   static char ID; // Pass identification, replacement for typeid
   StringRef getPassName() const override { return "AddressSanitizerModule"; }
@@ -656,6 +664,7 @@ private:
   bool CompileKernel;
   bool Recover;
   bool UseGlobalsGC;
+  bool UseCtorComdat;
   Type *IntptrTy;
   LLVMContext *C;
   Triple TargetTriple;
@@ -1677,7 +1686,7 @@ AddressSanitizerModule::CreateMetadataGlobal(Module &M, Constant *Initializer,
                      : GlobalVariable::PrivateLinkage;
   GlobalVariable *Metadata = new GlobalVariable(
       M, Initializer->getType(), false, Linkage, Initializer,
-      Twine("__asan_global_") + GlobalValue::getRealLinkageName(OriginalName));
+      Twine("__asan_global_") + GlobalValue::dropLLVMManglingEscape(OriginalName));
   Metadata->setSection(getGlobalMetadataSection());
   return Metadata;
 }
@@ -1782,7 +1791,7 @@ void AddressSanitizerModule::InstrumentGlobalsMachO(
   // On recent Mach-O platforms, use a structure which binds the liveness of
   // the global variable to the metadata struct. Keep the list of "Liveness" GV
   // created to be added to llvm.compiler.used
-  StructType *LivenessTy = StructType::get(IntptrTy, IntptrTy, nullptr);
+  StructType *LivenessTy = StructType::get(IntptrTy, IntptrTy);
   SmallVector<GlobalValue *, 16> LivenessGlobals(ExtendedGlobals.size());
 
   for (size_t i = 0; i < ExtendedGlobals.size(); i++) {
@@ -1793,9 +1802,9 @@ void AddressSanitizerModule::InstrumentGlobalsMachO(
 
     // On recent Mach-O platforms, we emit the global metadata in a way that
     // allows the linker to properly strip dead globals.
-    auto LivenessBinder = ConstantStruct::get(
-        LivenessTy, Initializer->getAggregateElement(0u),
-        ConstantExpr::getPointerCast(Metadata, IntptrTy), nullptr);
+    auto LivenessBinder =
+        ConstantStruct::get(LivenessTy, Initializer->getAggregateElement(0u),
+                            ConstantExpr::getPointerCast(Metadata, IntptrTy));
     GlobalVariable *Liveness = new GlobalVariable(
         M, LivenessTy, false, GlobalVariable::InternalLinkage, LivenessBinder,
         Twine("__asan_binder_") + G->getName());
@@ -1893,7 +1902,7 @@ bool AddressSanitizerModule::InstrumentGlobals(IRBuilder<> &IRB, Module &M, bool
   // We initialize an array of such structures and pass it to a run-time call.
   StructType *GlobalStructTy =
       StructType::get(IntptrTy, IntptrTy, IntptrTy, IntptrTy, IntptrTy,
-                      IntptrTy, IntptrTy, IntptrTy, nullptr);
+                      IntptrTy, IntptrTy, IntptrTy);
   SmallVector<GlobalVariable *, 16> NewGlobals(n);
   SmallVector<Constant *, 16> Initializers(n);
 
@@ -1929,10 +1938,9 @@ bool AddressSanitizerModule::InstrumentGlobals(IRBuilder<> &IRB, Module &M, bool
     assert(((RightRedzoneSize + SizeInBytes) % MinRZ) == 0);
     Type *RightRedZoneTy = ArrayType::get(IRB.getInt8Ty(), RightRedzoneSize);
 
-    StructType *NewTy = StructType::get(Ty, RightRedZoneTy, nullptr);
-    Constant *NewInitializer =
-        ConstantStruct::get(NewTy, G->getInitializer(),
-                            Constant::getNullValue(RightRedZoneTy), nullptr);
+    StructType *NewTy = StructType::get(Ty, RightRedZoneTy);
+    Constant *NewInitializer = ConstantStruct::get(
+        NewTy, G->getInitializer(), Constant::getNullValue(RightRedZoneTy));
 
     // Create a new global variable with enough space for a redzone.
     GlobalValue::LinkageTypes Linkage = G->getLinkage();
@@ -2013,7 +2021,7 @@ bool AddressSanitizerModule::InstrumentGlobals(IRBuilder<> &IRB, Module &M, bool
         ConstantExpr::getPointerCast(Name, IntptrTy),
         ConstantExpr::getPointerCast(ModuleName, IntptrTy),
         ConstantInt::get(IntptrTy, MD.IsDynInit), SourceLoc,
-        ConstantExpr::getPointerCast(ODRIndicator, IntptrTy), nullptr);
+        ConstantExpr::getPointerCast(ODRIndicator, IntptrTy));
 
     if (ClInitializers && MD.IsDynInit) HasDynamicallyInitializedGlobals = true;
 
@@ -2073,7 +2081,7 @@ bool AddressSanitizerModule::runOnModule(Module &M) {
   // Put the constructor and destructor in comdat if both
   // (1) global instrumentation is not TU-specific
   // (2) target is ELF.
-  if (ClWithComdat && TargetTriple.isOSBinFormatELF() && CtorComdat) {
+  if (UseCtorComdat && TargetTriple.isOSBinFormatELF() && CtorComdat) {
     AsanCtorFunction->setComdat(M.getOrInsertComdat(kAsanModuleCtorName));
     appendToGlobalCtors(M, AsanCtorFunction, kAsanCtorAndDtorPriority,
                         AsanCtorFunction);