diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index ec6058afd963c7e5d7eb9413fbc0f17b965b771d..30c5d28c227eb4960a29fa2a61051e155915cd31 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -763,7 +763,8 @@ RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo,
       
       if (CE->getOpcode() == llvm::Instruction::BitCast &&
           ActualFT->getReturnType() == CurFT->getReturnType() &&
-          ActualFT->getNumParams() == CurFT->getNumParams()) {
+          ActualFT->getNumParams() == CurFT->getNumParams() &&
+          ActualFT->getNumParams() == Args.size()) {
         bool ArgsMatch = true;
         for (unsigned i = 0, e = ActualFT->getNumParams(); i != e; ++i)
           if (ActualFT->getParamType(i) != CurFT->getParamType(i)) {
diff --git a/clang/test/CodeGen/functions.c b/clang/test/CodeGen/functions.c
index 985599216e1cb8790832e375d6801f08c12985e3..12dff1b72cbc02851b3f232ab36fd986d58f05dd 100644
--- a/clang/test/CodeGen/functions.c
+++ b/clang/test/CodeGen/functions.c
@@ -33,3 +33,7 @@ void f1() {}
 // RUN: grep 'define .* @f3' %t | not grep -F '...'
 struct foo { int X, Y, Z; } f3() {
 }
+
+// PR4423 - This shouldn't crash in codegen
+void f4() {}
+void f5() { f4(42); }