Set dso_local on vtables

[rnk]

lgtm

[• espindola]

328238

lib/CodeGen/ItaniumCXXABI.cpp

void ItaniumRTTIBuilder::BuildVTablePointer(const Type *Ty) {
   static const char * const SIClassTypeInfo =
     "_ZTVN10__cxxabiv120__si_class_type_infoE";
   // abi::__vmi_class_type_info.
   static const char * const VMIClassTypeInfo =
     "_ZTVN10__cxxabiv121__vmi_class_type_infoE";
 
   const char *VTableName = nullptr;
 
+  const CXXRecordDecl *RD = nullptr;
   switch (Ty->getTypeClass()) {
 #define TYPE(Class, Base)
 #define ABSTRACT_TYPE(Class, Base)
 #define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
 #define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
 #define DEPENDENT_TYPE(Class, Base) case Type::Class:
 #include "clang/AST/TypeNodes.def"
     llvm_unreachable("Non-canonical and dependent types shouldn't get here");
case Type::FunctionProto:
     break;
 
   case Type::Enum:
     // abi::__enum_type_info.
     VTableName = "_ZTVN10__cxxabiv116__enum_type_infoE";
     break;
 
   case Type::Record: {
-    const CXXRecordDecl *RD =
-      cast<CXXRecordDecl>(cast<RecordType>(Ty)->getDecl());
+    RD = cast<CXXRecordDecl>(cast<RecordType>(Ty)->getDecl());
 
     if (!RD->hasDefinition() || !RD->getNumBases()) {
       VTableName = ClassTypeInfo;
     } else if (CanUseSingleInheritance(RD)) {
       VTableName = SIClassTypeInfo;
     } else {
       VTableName = VMIClassTypeInfo;
     }
#include "clang/AST/TypeNodes.def"
   case Type::MemberPointer:
     // abi::__pointer_to_member_type_info.
     VTableName = "_ZTVN10__cxxabiv129__pointer_to_member_type_infoE";
     break;
   }
 
   llvm::Constant *VTable =
     CGM.getModule().getOrInsertGlobal(VTableName, CGM.Int8PtrTy);
+  CGM.setGVProperties(cast<llvm::GlobalValue>(VTable->stripPointerCasts()), RD);
 
   llvm::Type *PtrDiffTy =
     CGM.getTypes().ConvertType(CGM.getContext().getPointerDiffType());
 
   // The vtable address point is 2.
   llvm::Constant *Two = llvm::ConstantInt::get(PtrDiffTy, 2);
   VTable =
       llvm::ConstantExpr::getInBoundsGetElementPtr(CGM.Int8PtrTy, VTable, Two);

test/CodeGenCXX/dllexport.cpp

 // Globals
 //===----------------------------------------------------------------------===//
 
 // Declarations are not exported.
 // MSC-NOT: @"?ExternGlobalDecl@@3HA"
 // GNU-NOT: @ExternGlobalDecl
 __declspec(dllexport) extern int ExternGlobalDecl;
 
+// GNU-DAG: @_ZTVN10__cxxabiv117__class_type_infoE = external dso_local global
+
 // dllexport implies a definition.
 // MSC-DAG: @"?GlobalDef@@3HA" = dso_local dllexport global i32 0, align 4
 // GNU-DAG: @GlobalDef            = dso_local dllexport global i32 0, align 4
 __declspec(dllexport) int GlobalDef;
 
 // Export definition.
 // MSC-DAG: @"?GlobalInit1@@3HA" = dso_local dllexport global i32 1, align 4
 // GNU-DAG: @GlobalInit1            = dso_local dllexport global i32 1, align 4