From: Hans Wennborg <hans@hanshq.net>
Date: Wed, 22 Apr 2015 04:05:17 +0000 (+0000)
Subject: Don't dllimport/export class members with internal linkage (PR23308)
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=26a663ab48dbe7db656ee75d03044bd72c6cad17;p=clang

Don't dllimport/export class members with internal linkage (PR23308)

For example, a function taking a parameter with internal linkage will
itself have internal linkage since it cannot be called outside the
translation unit.

Differential Revision: http://reviews.llvm.org/D9182

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@235471 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index b0e6acaedb..b06b509de1 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -4804,6 +4804,9 @@ static void checkDLLAttribute(Sema &S, CXXRecordDecl *Class) {
       }
     }
 
+    if (!cast<NamedDecl>(Member)->isExternallyVisible())
+      continue;
+
     if (!getDLLAttr(Member)) {
       auto *NewAttr =
           cast<InheritableAttr>(ClassAttr->clone(S.getASTContext()));
diff --git a/test/CodeGenCXX/dllexport.cpp b/test/CodeGenCXX/dllexport.cpp
index b7bd675602..cc66a66877 100644
--- a/test/CodeGenCXX/dllexport.cpp
+++ b/test/CodeGenCXX/dllexport.cpp
@@ -691,6 +691,15 @@ extern template struct ExplicitInstantiationDeclExportedTemplate<int>;
 USEMEMFUNC(ExplicitInstantiationDeclExportedTemplate<int>, f);
 // M32-DAG: {{declare|define available_externally}} x86_thiscallcc void @"\01?f@?$ExplicitInstantiationDeclExportedTemplate@H@@QAEXXZ"
 
+namespace { struct InternalLinkageType {}; }
+struct __declspec(dllexport) PR23308 {
+  void f(InternalLinkageType*);
+};
+void PR23308::f(InternalLinkageType*) {}
+long use(PR23308* p) { p->f(nullptr); }
+// M32-DAG: define internal x86_thiscallcc void @"\01?f@PR23308@@QAEXPAUInternalLinkageType@?A@@@Z"
+
+
 
 //===----------------------------------------------------------------------===//
 // Classes with template base classes
diff --git a/test/SemaCXX/dllexport.cpp b/test/SemaCXX/dllexport.cpp
index 3bb9d224f7..3b9b20d72d 100644
--- a/test/SemaCXX/dllexport.cpp
+++ b/test/SemaCXX/dllexport.cpp
@@ -393,6 +393,12 @@ extern template struct __declspec(dllexport) ExplicitInstantiationDeclTemplate<i
 template <typename T> struct __declspec(dllexport) ExplicitInstantiationDeclExportedTemplate {}; // expected-note{{attribute is here}}
 extern template struct ExplicitInstantiationDeclExportedTemplate<int>; // expected-warning{{explicit instantiation declaration should not be 'dllexport'}}
 
+namespace { struct InternalLinkageType {}; }
+struct __declspec(dllexport) PR23308 {
+  void f(InternalLinkageType*);
+};
+void PR23308::f(InternalLinkageType*) {} // No error; we don't try to export f because it has internal linkage.
+
 //===----------------------------------------------------------------------===//
 // Classes with template base classes
 //===----------------------------------------------------------------------===//