Index: lib/Transforms/Instrumentation/AddressSanitizer.cpp =================================================================== --- lib/Transforms/Instrumentation/AddressSanitizer.cpp +++ lib/Transforms/Instrumentation/AddressSanitizer.cpp @@ -1609,22 +1609,12 @@ GlobalVariable * AddressSanitizerModule::CreateMetadataGlobal(Module &M, Constant *Initializer, StringRef OriginalName) { - auto &DL = M.getDataLayout(); GlobalVariable *Metadata = new GlobalVariable(M, Initializer->getType(), false, GlobalVariable::InternalLinkage, Initializer, Twine("__asan_global_") + GlobalValue::getRealLinkageName(OriginalName)); Metadata->setSection(getGlobalMetadataSection()); - - // We don't want any padding, but we also need a reasonable alignment. - // The MSVC linker always inserts padding when linking incrementally. We - // cope with that by aligning each struct to its size, which must be a power - // of two. - unsigned SizeOfGlobalStruct = DL.getTypeAllocSize(Initializer->getType()); - assert(isPowerOf2_32(SizeOfGlobalStruct) && - "global metadata will not be padded appropriately"); - Metadata->setAlignment(SizeOfGlobalStruct); return Metadata; } @@ -1642,11 +1632,22 @@ IRBuilder<> &IRB, Module &M, ArrayRef ExtendedGlobals, ArrayRef MetadataInitializers) { assert(ExtendedGlobals.size() == MetadataInitializers.size()); + auto &DL = M.getDataLayout(); for (size_t i = 0; i < ExtendedGlobals.size(); i++) { + Constant *Initializer = MetadataInitializers[i]; GlobalVariable *G = ExtendedGlobals[i]; GlobalVariable *Metadata = - CreateMetadataGlobal(M, MetadataInitializers[i], G->getName()); + CreateMetadataGlobal(M, Initializer, G->getName()); + + // The MSVC linker always inserts padding when linking incrementally. We + // cope with that by aligning each struct to its size, which must be a power + // of two. + unsigned SizeOfGlobalStruct = DL.getTypeAllocSize(Initializer->getType()); + assert(isPowerOf2_32(SizeOfGlobalStruct) && + "global metadata will not be padded appropriately"); + Metadata->setAlignment(SizeOfGlobalStruct); + SetComdatForGlobalMetadata(G, Metadata); } } Index: test/Instrumentation/AddressSanitizer/global_metadata_darwin.ll =================================================================== --- test/Instrumentation/AddressSanitizer/global_metadata_darwin.ll +++ test/Instrumentation/AddressSanitizer/global_metadata_darwin.ll @@ -16,7 +16,7 @@ ; Find the metadata for @global: -; CHECK: [[METADATA:@.+]] = internal global {{.*}} @global {{.*}} section "__DATA,__asan_globals,regular", align 64 +; CHECK: [[METADATA:@.+]] = internal global {{.*}} @global {{.*}} section "__DATA,__asan_globals,regular" ; Find the liveness binder for @global and its metadata: ; CHECK: @__asan_binder_global = internal global {{.*}} @global {{.*}} [[METADATA]] {{.*}} section "__DATA,__asan_liveness,regular,live_support"