diff --git a/CodeGen/ModuleBuilder.cpp b/CodeGen/ModuleBuilder.cpp
index 49881c3..fff5b3f 100644
--- a/CodeGen/ModuleBuilder.cpp
+++ b/CodeGen/ModuleBuilder.cpp
@@ -13,6 +13,7 @@
 
 #include "clang/CodeGen/ModuleBuilder.h"
 #include "CodeGenModule.h"
+#include "clang/AST/Decl.h"
 using namespace clang;
 
 
@@ -34,6 +35,16 @@
   B->EmitFunction(D);
 }
 
+/// CodeGenLinkageSpec - Emit the specified linkage space to LLVM.
+void clang::CodeGen::CodeGenLinkageSpec(CodeGenModule *Builder,
+					LinkageSpecDecl *LS) {
+  if (LS->getLanguage() == LinkageSpecDecl::lang_cxx)
+    Builder->WarnUnsupported(LS, "linkage spec");
+
+  // FIXME: implement C++ linkage, C linkage works mostly by C
+  // language reuse already.
+}
+
 /// CodeGenGlobalVar - Emit the specified global variable to LLVM.
 void clang::CodeGen::CodeGenGlobalVar(CodeGenModule *Builder, FileVarDecl *D) {
   Builder->EmitGlobalVarDeclarator(D);