From 3bd0a1586712e40972269074283b35196aee0ddc Mon Sep 17 00:00:00 2001
From: Hans Wennborg <hans@hanshq.net>
Date: Tue, 13 Feb 2018 09:19:43 +0000
Subject: [PATCH] Fix for PR32992. Static const classes not exported.

Patch by zahiraam!

Differential Revision: https://reviews.llvm.org/D42968

llvm-svn: 324991
---
 clang/lib/Sema/SemaDeclCXX.cpp      | 16 +++++++++++++---
 clang/test/CodeGenCXX/dllexport.cpp | 19 +++++++++++++++++++
 2 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 45adbe3a16ed..d3f3a1a93821 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -5476,7 +5476,7 @@ static void CheckAbstractClassUsage(AbstractUsageInfo &Info,
   }
 }
 
-static void ReferenceDllExportedMethods(Sema &S, CXXRecordDecl *Class) {
+static void ReferenceDllExportedMembers(Sema &S, CXXRecordDecl *Class) {
   Attr *ClassAttr = getDLLAttr(Class);
   if (!ClassAttr)
     return;
@@ -5491,6 +5491,16 @@ static void ReferenceDllExportedMethods(Sema &S, CXXRecordDecl *Class) {
     return;
 
   for (Decl *Member : Class->decls()) {
+    // Defined static variables that are members of an exported base
+    // class must be marked export too. Push them to implicit instantiation
+    // queue.
+    auto *VD = dyn_cast<VarDecl>(Member);
+    if (VD && Member->getAttr<DLLExportAttr>() &&
+        VD->getStorageClass() == SC_Static &&
+        TSK == TSK_ImplicitInstantiation)
+      S.PendingLocalImplicitInstantiations.push_back(
+          std::make_pair(VD, VD->getLocation()));
+
     auto *MD = dyn_cast<CXXMethodDecl>(Member);
     if (!MD)
       continue;
@@ -10902,12 +10912,12 @@ void Sema::ActOnFinishCXXNonNestedClass(Decl *D) {
 
 void Sema::referenceDLLExportedClassMethods() {
   if (!DelayedDllExportClasses.empty()) {
-    // Calling ReferenceDllExportedMethods might cause the current function to
+    // Calling ReferenceDllExportedMembers might cause the current function to
     // be called again, so use a local copy of DelayedDllExportClasses.
     SmallVector<CXXRecordDecl *, 4> WorkList;
     std::swap(DelayedDllExportClasses, WorkList);
     for (CXXRecordDecl *Class : WorkList)
-      ReferenceDllExportedMethods(*this, Class);
+      ReferenceDllExportedMembers(*this, Class);
   }
 }
 
diff --git a/clang/test/CodeGenCXX/dllexport.cpp b/clang/test/CodeGenCXX/dllexport.cpp
index a446147b6cdc..97ce5b54c4eb 100644
--- a/clang/test/CodeGenCXX/dllexport.cpp
+++ b/clang/test/CodeGenCXX/dllexport.cpp
@@ -28,6 +28,7 @@ struct External { int v; };
 
 // The vftable for struct W is comdat largest because we have RTTI.
 // M32-DAG: $"\01??_7W@@6B@" = comdat largest
+// M32-DAG: $"\01?smember@?$Base@H@PR32992@@0HA" = comdat any
 
 
 //===----------------------------------------------------------------------===//
@@ -977,3 +978,21 @@ class __declspec(dllexport) ACE_Service_Object : public ACE_Shared_Object {};
 // MSVC2015-DAG: define weak_odr dllexport {{.+}}ACE_Service_Object@@Q{{.+}}@$$Q
 // The declarations should not be exported.
 // MSVC2013-NOT: define weak_odr dllexport {{.+}}ACE_Service_Object@@Q{{.+}}@$$Q
+
+namespace PR32992 {
+// Static data members of a instantiated base class should be exported.
+template <class T>
+class Base {
+  virtual void myfunc() {}
+  static int smember;
+};
+// MS-DAG:  @"\01?smember@?$Base@H@PR32992@@0HA" = weak_odr dllexport global i32 77, comdat, align 4
+template <class T> int Base<T>::smember = 77;
+template <class T>
+class __declspec(dllexport) Derived2 : Base<T> {
+  void myfunc() {}
+};
+class Derived : public Derived2<int> {
+  void myfunc() {}
+};
+}  // namespace PR32992