hanchenye-llvm-project/clang/test/CodeGen/2007-04-14-FNoBuiltin.c

// RUN: %clang_cc1 -emit-llvm %s -O2 -fno-builtin -o - | grep call.*printf
// Check that -fno-builtin is honored.

extern int printf(const char*, ...);
void foo(const char *msg) {
	printf("%s\n",msg);
}