Propagate DLLAttr to friend re-declarations of member functions

...that have already been constructed (e.g., in inner classes) while parsing the
class definition.  They would otherwise lack any DLLAttr inherited from the
class, which are only set here (called from Sema::CheckCompletedClass) after the
class definition has been parsed completely.

Differential revision: https://reviews.llvm.org/D16632

llvm-svn: 326990

2 files changed, 25 insertions, 0 deletions

diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 51ba96fb1e8..9e3647548be 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -5685,6 +5685,21 @@ void Sema::checkClassLevelDLLAttribute(CXXRecordDecl *Class) {
           cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
       NewAttr->setInherited(true);
       Member->addAttr(NewAttr);
+
+      if (MD) {
+        // Propagate DLLAttr to friend re-declarations of MD that have already
+        // been constructed.
+        for (FunctionDecl *FD = MD->getMostRecentDecl(); FD;
+             FD = FD->getPreviousDecl()) {
+          if (FD->getFriendObjectKind() == Decl::FOK_None)
+            continue;
+          assert(!getDLLAttr(FD) &&
+                 "friend re-decl should not already have a DLLAttr");
+          NewAttr = cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
+          NewAttr->setInherited(true);
+          FD->addAttr(NewAttr);
+        }
+      }
     }
   }
 
diff --git a/clang/test/CodeGenCXX/dllexport.cpp b/clang/test/CodeGenCXX/dllexport.cpp
index 4155940f77e..82360557ee6 100644
--- a/clang/test/CodeGenCXX/dllexport.cpp
+++ b/clang/test/CodeGenCXX/dllexport.cpp
@@ -290,6 +290,16 @@ struct FuncFriend {
 __declspec(dllexport) void friend1() {}
                       void friend2() {}
 
+// MSC-DAG: define dso_local dllexport void @"\01?func@Befriended@@SAXXZ"()
+// GNU-DAG: define dso_local dllexport void @_ZN10Befriended4funcEv()
+struct __declspec(dllexport) Befriended {
+  static void func();
+  struct Befriending {
+    friend void Befriended::func();
+  };
+};
+void Befriended::func() {}
+
 // Implicit declarations can be redeclared with dllexport.
 // MSC-DAG: define dso_local dllexport noalias i8* @"\01??2@{{YAPAXI|YAPEAX_K}}@Z"(
 // GNU-DAG: define dso_local dllexport noalias i8* @_Znw{{[yj]}}(