modernc.org/ccgo/v3@v3.16.14/lib/testdata/gcc-9.1.0/gcc/testsuite/gcc.c-torture/execute/loop-2f.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
    31  
    32  
    33  f (int s, char *p)
    34  {
    35    int i;
    36    for (i = s; i >= 0 && &p[i] < &p[40]; i++)
    37      {
    38        p[i] = -2;
    39      }
    40  }
    41  
    42  main ()
    43  {
    44  #ifdef MAP_ANON
    45    char *p;
    46    int dev_zero;
    47  
    48    dev_zero = open ("/dev/zero", O_RDONLY);
    49    /* -1 is OK when we have MAP_ANON; else mmap will flag an error.  */
    50    if (INT_MAX != 0x7fffffffL || sizeof (char *) != sizeof (int))
    51      exit (0);
    52    p = mmap (MAP_START, MAP_LEN, PROT_READ|PROT_WRITE,
    53  	    MAP_ANON|MAP_FIXED|MAP_PRIVATE, dev_zero, 0);
    54    if (p != (char *)-1)
    55      {
    56        p += OFFSET;
    57        p[39] = 0;
    58        f (0, p);
    59        if (p[39] != (char)-2)
    60  	abort ();
    61        p[39] = 0;
    62        f (-1, p);
    63        if (p[39] != 0)
    64  	abort ();
    65      }
    66  #endif
    67    exit (0);
    68  }