blob: 9101fb0227a065a1a2f4dbada728f0446728f6c3 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
|
/* Test whether strncmp has not been "optimized" into memcmp
nor any code with memcmp semantics. */
/* { dg-do run { target i?86-*-linux* x86_64-*-linux* ia64-*-linux* alpha*-*-linux* powerpc*-*-linux* s390*-*-linux* sparc*-*-linux* *-*-darwin* } } */
/* { 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
#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;
}
|
