diff --git a/llvm/test/Regression/CFrontend/2006-01-16-BitCountIntrinsicsUnsigned.c b/llvm/test/Regression/CFrontend/2006-01-16-BitCountIntrinsicsUnsigned.c
new file mode 100644
index 000000000000..87909764ab94
--- /dev/null
+++ b/llvm/test/Regression/CFrontend/2006-01-16-BitCountIntrinsicsUnsigned.c
@@ -0,0 +1,9 @@
+// RUN: %llvmgcc -S %s -o - | grep 'llvm.ctlz.i32(uint' &&
+// RUN: %llvmgcc -S %s -o - | not grep 'llvm.ctlz.i32(int'
+
+unsigned t2(unsigned X) {
+  return __builtin_clz(X);
+}
+int t1(int X) {
+  return __builtin_clz(X);
+}