diff --git a/llvm/lib/Transforms/IPO/FunctionSpecialization.cpp b/llvm/lib/Transforms/IPO/FunctionSpecialization.cpp
--- a/llvm/lib/Transforms/IPO/FunctionSpecialization.cpp
+++ b/llvm/lib/Transforms/IPO/FunctionSpecialization.cpp
@@ -662,6 +662,12 @@
       if (!isa<CallInst>(U) && !isa<InvokeInst>(U))
         continue;
       auto &CS = *cast<CallBase>(U);
+
+      // This should not happen at the moment; however, it may if we start
+      // specializing functions that have their addresses taken.
+      assert(CS.getCalledFunction() == F && 
+             "Function and callee should be same!");
+
       // If the call site has attribute minsize set, that callsite won't be
       // specialized.
       if (CS.hasFnAttr(Attribute::MinSize)) {