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/* Test whether strncmp has not been "optimized" into memcmp
nor any code with memcmp semantics. */
/* { dg-do run { target mmap } } */
/* { dg-options "-O2" } */
#include <stddef.h>
#include <stdio.h>
#include <sys/mman.h>
/* Darwin spells this differently */
#ifndef MAP_ANONYMOUS
#define MAP_ANONYMOUS MAP_ANON
#endif
#ifndef MAP_ANON
#define MAP_ANON 0
#endif
#include <stdlib.h>
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;
}
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