/* Test whether strncmp has not been "optimized" into memcmp nor any code with memcmp semantics. */ /* { dg-do run { target mmap } } */ /* { dg-options "-O2" } */ #include #include #include /* Darwin spells this differently */ #ifndef MAP_ANONYMOUS #define MAP_ANONYMOUS MAP_ANON #endif #ifndef MAP_ANON #define MAP_ANON 0 #endif #ifndef MAP_FAILED #define MAP_FAILED ((void *)-1) #endif #include struct Flags { int filler[18]; unsigned int a:14; unsigned int b:14; unsigned int c:1; unsigned int d:1; unsigned int e:1; unsigned int f:1; }; static void __attribute__((noinline)) set (struct Flags *); static void set (struct Flags *fp) { fp->b = 5; fp->d = 1; } static int __attribute__((noinline)) bar (int); static int bar(int x) { return !(x==1); } int main (void) { char *p = mmap (NULL, 131072, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); struct Flags *fp; if (p == MAP_FAILED) return 0; if (munmap (p + 65536, 65536) < 0) return 0; fp = (struct Flags*)(p + 65536 - sizeof(struct Flags)); set(fp); if (fp->b > 0) return (bar(fp->d)); return 1; }