diff --git a/lib/Linker/LinkModules.cpp b/lib/Linker/LinkModules.cpp
index d6f4ef81d74..cba6f1a3181 100644
--- a/lib/Linker/LinkModules.cpp
+++ b/lib/Linker/LinkModules.cpp
@@ -1532,10 +1532,8 @@ bool ModuleLinker::run() {
     GlobalValue *SGV = LazilyLinkGlobalValues.back();
     LazilyLinkGlobalValues.pop_back();
 
-    if (isa<Function>(SGV))
-      assert(!cast<Function>(SGV)->isDeclaration() &&
-             "users should not pass down decls");
-
+    assert((!isa<Function>(SGV) || !cast<Function>(SGV)->isDeclaration()) &&
+           "users should not pass down decls");
     if (linkGlobalValueBody(*SGV))
       return true;
   }