modernc.org/ccgo/v3@v3.16.14/lib/testdata/gcc-9.1.0/gcc/testsuite/gcc.c-torture/execute/loop-2g.c (about)

     1  /* { dg-require-effective-target mmap } */
     2  /* { dg-skip-if "the executable is at the same position the test tries to remap" { m68k-*-linux* } } */
     3  
     4  #include <limits.h>
     5  
     6  #include <sys/types.h>
     7  #if !defined(__MINGW32__) && !defined(__MINGW64__)
     8  #include <sys/mman.h>
     9  #include <sys/stat.h>
    10  #include <fcntl.h>
    11  #ifndef MAP_ANON
    12  #ifdef MAP_ANONYMOUS
    13  #define MAP_ANON MAP_ANONYMOUS
    14  #else
    15  #define MAP_ANON MAP_FILE
    16  #endif
    17  #endif
    18  #ifndef MAP_FILE
    19  #define MAP_FILE 0
    20  #endif
    21  #ifndef MAP_FIXED
    22  #define MAP_FIXED 0
    23  #endif
    24  
    25  #define MAP_START (void *)0x7fff8000
    26  #define MAP_LEN 0x10000
    27  
    28  #define OFFSET (MAP_LEN/2 - 2 * sizeof (char));
    29  
    30  #endif // mingw
    31  
    32  f (int s, char *p)
    33  {
    34    int i;
    35    for (i = s; &p[i] < &p[40] && i >= 0; i++)
    36      {
    37        p[i] = -2;
    38      }
    39  }
    40  
    41  main ()
    42  {
    43  #ifdef MAP_ANON
    44    char *p;
    45    int dev_zero;
    46  
    47    dev_zero = open ("/dev/zero", O_RDONLY);
    48    /* -1 is OK when we have MAP_ANON; else mmap will flag an error.  */
    49    if (INT_MAX != 0x7fffffffL || sizeof (char *) != sizeof (int))
    50      exit (0);
    51    p = mmap (MAP_START, MAP_LEN, PROT_READ|PROT_WRITE,
    52  	    MAP_ANON|MAP_FIXED|MAP_PRIVATE, dev_zero, 0);
    53    if (p != (char *)-1)
    54      {
    55        p += OFFSET;
    56        p[39] = 0;
    57        f (0, p);
    58        if (p[39] != (char)-2)
    59  	abort ();
    60        p[39] = 0;
    61        f (-1, p);
    62        if (p[39] != 0)
    63  	abort ();
    64      }
    65  #endif
    66    exit (0);
    67  }