Index: include/clang/AST/ASTContext.h
===================================================================
--- include/clang/AST/ASTContext.h
+++ include/clang/AST/ASTContext.h
@@ -2283,6 +2283,10 @@
   void getObjCEncodingForMethodParameter(Decl::ObjCDeclQualifier QT,
                                          QualType T, std::string& S,
                                          bool Extended) const;
+
+  /// \brief Returns true if this is an inline-initialized static data member
+  /// which the MS ABI treats as a definition.
+  bool isMSStaticDataMemberInlineDefinition(const VarDecl *VD) const;
   
 private:
   const ASTRecordLayout &
Index: lib/AST/ASTContext.cpp
===================================================================
--- lib/AST/ASTContext.cpp
+++ lib/AST/ASTContext.cpp
@@ -4781,6 +4781,14 @@
   return sz;
 }
 
+bool ASTContext::isMSStaticDataMemberInlineDefinition(const VarDecl *VD) const {
+  return VD->isStaticDataMember() &&
+         VD->getType()->isIntegralOrEnumerationType() &&
+         getTargetInfo().getCXXABI().isMicrosoft() &&
+         !VD->getFirstDecl()->isOutOfLine() &&
+         VD->getFirstDecl()->hasInit();
+}
+
 static inline 
 std::string charUnitsToString(const CharUnits &CU) {
   return llvm::itostr(CU.getQuantity());
@@ -7849,6 +7857,12 @@
                                                : StaticLocalLinkage;
   }
 
+  // MSVC treats in-class initialized static data members as definitions.
+  // By giving them non-strong linkage, out-of-line definitions won't
+  // cause link errors.
+  if (Context.isMSStaticDataMemberInlineDefinition(VD))
+    return GVA_DiscardableODR;
+
   switch (VD->getTemplateSpecializationKind()) {
   case TSK_Undeclared:
   case TSK_ExplicitSpecialization:
@@ -7934,7 +7948,8 @@
   const VarDecl *VD = cast<VarDecl>(D);
   assert(VD->isFileVarDecl() && "Expected file scoped var");
 
-  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly)
+  if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly &&
+      !isMSStaticDataMemberInlineDefinition(VD))
     return false;
 
   // Variables that can be needed in other TUs are required.
Index: lib/CodeGen/CGCXXABI.h
===================================================================
--- lib/CodeGen/CGCXXABI.h
+++ lib/CodeGen/CGCXXABI.h
@@ -403,10 +403,6 @@
   /// 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
Index: lib/CodeGen/CodeGenModule.cpp
===================================================================
--- lib/CodeGen/CodeGenModule.cpp
+++ lib/CodeGen/CodeGenModule.cpp
@@ -1256,7 +1256,8 @@
     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 @@
   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 @@
 
     // 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 @@
     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) &&
Index: lib/CodeGen/MicrosoftCXXABI.cpp
===================================================================
--- lib/CodeGen/MicrosoftCXXABI.cpp
+++ lib/CodeGen/MicrosoftCXXABI.cpp
@@ -55,8 +55,6 @@
   // arbitrary.
   StringRef GetDeletedVirtualCallName() override { return "_purecall"; }
 
-  bool isInlineInitializedStaticDataMemberLinkOnce() override { return true; }
-
   llvm::Value *adjustToCompleteObject(CodeGenFunction &CGF,
                                       llvm::Value *ptr,
                                       QualType type) override;
Index: lib/CodeGen/ModuleBuilder.cpp
===================================================================
--- lib/CodeGen/ModuleBuilder.cpp
+++ lib/CodeGen/ModuleBuilder.cpp
@@ -12,6 +12,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang/CodeGen/ModuleBuilder.h"
+#include "CGCXXABI.h"
 #include "CGDebugInfo.h"
 #include "CodeGenModule.h"
 #include "clang/AST/ASTContext.h"
@@ -128,6 +129,19 @@
         return;
 
       Builder->UpdateCompletedType(D);
+
+      // If required by the ABI, treat declarations of static data members with
+      // inline initializers as definitions.
+      if (Ctx->getTargetInfo().getCXXABI().isMicrosoft()) {
+        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 {
Index: test/CodeGenCXX/ms-integer-static-data-members-exported.cpp
===================================================================
--- /dev/null
+++ test/CodeGenCXX/ms-integer-static-data-members-exported.cpp
@@ -0,0 +1,22 @@
+// RUN: %clang_cc1 -emit-llvm -triple=i386-pc-win32 %s -o - | FileCheck %s
+
+enum Enum { zero, one, two };
+
+struct __declspec(dllexport) S {
+  // In the MS ABI, this counts as a definition.
+  // Since it is exported, it must be emitted even if it's unreferenced.
+  static const short x = 42;
+
+  // This works for enums too.
+  static const Enum y = two;
+
+  struct NonExported {
+    // dllexport is not inherited by this nested class.
+    // Since z is not referenced, it should not be emitted.
+    static const int z = 42;
+  };
+};
+
+// CHECK: @"\01?x@S@@2FB" = weak_odr dllexport constant i16 42, align 2
+// CHECK: @"\01?y@S@@2W4Enum@@B" = weak_odr dllexport constant i32 2, align 4
+// CHECK-NOT: NonExported