4 files changed, 17 insertions, 33 deletions

diff --git a/clang/lib/CodeGen/CGCXXABI.h b/clang/lib/CodeGen/CGCXXABI.h
index b49c68a4df1..91e49707bae 100644
--- a/clang/lib/CodeGen/CGCXXABI.h
+++ b/clang/lib/CodeGen/CGCXXABI.h
@@ -403,10 +403,6 @@ public:
   /// Gets the deleted virtual member call name.
   virtual StringRef GetDeletedVirtualCallName() = 0;
 
-  /// \brief Returns true iff static data members that are initialized in the
-  /// class definition should have linkonce linkage.
-  virtual bool isInlineInitializedStaticDataMemberLinkOnce() { return false; }
-
   /**************************** Array cookies ******************************/
 
   /// Returns the extra size required in order to store the array
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 66ac524f2b9..6c33f922792 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -1256,7 +1256,8 @@ void CodeGenModule::EmitGlobal(GlobalDecl GD) {
     const auto *VD = cast<VarDecl>(Global);
     assert(VD->isFileVarDecl() && "Cannot emit local var decl as global.");
 
-    if (VD->isThisDeclarationADefinition() != VarDecl::Definition)
+    if (VD->isThisDeclarationADefinition() != VarDecl::Definition &&
+        !Context.isMSStaticDataMemberInlineDefinition(VD))
       return;
   }
 
@@ -1592,18 +1593,6 @@ bool CodeGenModule::isTypeConstant(QualType Ty, bool ExcludeCtor) {
   return true;
 }
 
-static bool isVarDeclInlineInitializedStaticDataMember(const VarDecl *VD) {
-  if (!VD->isStaticDataMember())
-    return false;
-  const VarDecl *InitDecl;
-  const Expr *InitExpr = VD->getAnyInitializer(InitDecl);
-  if (!InitExpr)
-    return false;
-  if (InitDecl->isThisDeclarationADefinition())
-    return false;
-  return true;
-}
-
 /// GetOrCreateLLVMGlobal - If the specified mangled name is not in the module,
 /// create and return an llvm GlobalVariable with the specified type.  If there
 /// is something in the module with the specified name, return it potentially
@@ -1666,9 +1655,9 @@ CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName,
 
     // If required by the ABI, treat declarations of static data members with
     // inline initializers as definitions.
-    if (getCXXABI().isInlineInitializedStaticDataMemberLinkOnce() &&
-        isVarDeclInlineInitializedStaticDataMember(D))
+    if (getContext().isMSStaticDataMemberInlineDefinition(D)) {
       EmitGlobalVarDefinition(D);
+    }
 
     // Handle XCore specific ABI requirements.
     if (getTarget().getTriple().getArch() == llvm::Triple::xcore &&
@@ -2087,18 +2076,6 @@ llvm::GlobalValue::LinkageTypes CodeGenModule::getLLVMLinkageForDeclarator(
     return !Context.getLangOpts().AppleKext ? llvm::Function::WeakODRLinkage
                                             : llvm::Function::ExternalLinkage;
 
-  // If required by the ABI, give definitions of static data members with inline
-  // initializers at least linkonce_odr linkage.
-  auto const VD = dyn_cast<VarDecl>(D);
-  if (getCXXABI().isInlineInitializedStaticDataMemberLinkOnce() &&
-      VD && isVarDeclInlineInitializedStaticDataMember(VD)) {
-    if (VD->hasAttr<DLLImportAttr>())
-      return llvm::GlobalValue::AvailableExternallyLinkage;
-    if (VD->hasAttr<DLLExportAttr>())
-      return llvm::GlobalValue::WeakODRLinkage;
-    return llvm::GlobalValue::LinkOnceODRLinkage;
-  }
-
   // C++ doesn't have tentative definitions and thus cannot have common
   // linkage.
   if (!getLangOpts().CPlusPlus && isa<VarDecl>(D) &&
diff --git a/clang/lib/CodeGen/MicrosoftCXXABI.cpp b/clang/lib/CodeGen/MicrosoftCXXABI.cpp
index 41b7574e34c..a69d4dd3fe8 100644
--- a/clang/lib/CodeGen/MicrosoftCXXABI.cpp
+++ b/clang/lib/CodeGen/MicrosoftCXXABI.cpp
@@ -55,8 +55,6 @@ public:
   // arbitrary.
   StringRef GetDeletedVirtualCallName() override { return "_purecall"; }
 
-  bool isInlineInitializedStaticDataMemberLinkOnce() override { return true; }
-
   llvm::Value *adjustToCompleteObject(CodeGenFunction &CGF,
                                       llvm::Value *ptr,
                                       QualType type) override;
diff --git a/clang/lib/CodeGen/ModuleBuilder.cpp b/clang/lib/CodeGen/ModuleBuilder.cpp
index c4a0e5c063d..c5d18d3286a 100644
--- a/clang/lib/CodeGen/ModuleBuilder.cpp
+++ b/clang/lib/CodeGen/ModuleBuilder.cpp
@@ -128,6 +128,19 @@ namespace {
         return;
 
       Builder->UpdateCompletedType(D);
+
+      // For MSVC compatibility, treat declarations of static data members with
+      // inline initializers as definitions.
+      if (Ctx->getLangOpts().MSVCCompat) {
+        for (Decl *Member : D->decls()) {
+          if (VarDecl *VD = dyn_cast<VarDecl>(Member)) {
+            if (Ctx->isMSStaticDataMemberInlineDefinition(VD) &&
+                Ctx->DeclMustBeEmitted(VD)) {
+              Builder->EmitGlobal(VD);
+            }
+          }
+        }
+      }
     }
 
     void HandleTagDeclRequiredDefinition(const TagDecl *D) override {