If a method is virtual and the class key function is in another file, emit the method as available_externally.

Fixes PR6747

llvm-svn: 101757

2 files changed, 17 insertions, 1 deletions

diff --git a/clang/lib/CodeGen/CGVTables.h b/clang/lib/CodeGen/CGVTables.h
index b4262fe224c..bc113ec42fa 100644
--- a/clang/lib/CodeGen/CGVTables.h
+++ b/clang/lib/CodeGen/CGVTables.h
@@ -295,6 +295,15 @@ public:
   CodeGenVTables(CodeGenModule &CGM)
     : CGM(CGM) { }
 
+  // isKeyFunctionInAnotherTU - True if this record has a key function and it is
+  // in another translation unit.
+  static bool isKeyFunctionInAnotherTU(ASTContext &Context,
+				       const CXXRecordDecl *RD) {
+    assert (RD->isDynamicClass() && "Non dynamic classes have no key.");
+    const CXXMethodDecl *KeyFunction = Context.getKeyFunction(RD);
+    return KeyFunction && !KeyFunction->getBody();
+  }
+
   /// needsVTTParameter - Return whether the given global decl needs a VTT
   /// parameter, which it does if it's a base constructor or destructor with
   /// virtual bases.
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index ab2f1c7aa2e..035e57fd0b2 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -314,7 +314,14 @@ GetLinkageForFunction(ASTContext &Context, const FunctionDecl *FD,
   if (FD->getTemplateSpecializationKind() 
                                        == TSK_ExplicitInstantiationDeclaration)
     return CodeGenModule::GVA_C99Inline;
-  
+
+  if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
+    const CXXRecordDecl *RD = MD->getParent();
+    if (MD->isVirtual() &&
+	CodeGenVTables::isKeyFunctionInAnotherTU(Context, RD))
+      return CodeGenModule::GVA_C99Inline;
+  }  
+
   return CodeGenModule::GVA_CXXInline;
 }