tests/tests2/133_exec_section_in_asm.c

   1 /* Previously in TinyCC, ELF sections defined in assembly would always have the
   2 execute bit not set, so you would get segmentation faults when code in these
   3 sections was exectuted. This file is a minimal example of a file that will put
   4 the resulting code in a non-executable section (and invoke it) prior to the fix.
   5 */
   6 #include <stdio.h>
   7
   8 void *memset(void *dst, int c, int len);
   9
  10 __asm__ (
  11 ".section .text.nolibc_memset\n"
  12 ".weak memset\n"
  13 "memset:\n"
  14         "xchgl %eax, %esi\n\t"
  15         "movq  %rdx, %rcx\n\t"
  16         "pushq %rdi\n\t"
  17         "rep stosb\n\t"
  18         "popq  %rax\n\t"
  19         "retq\n"
  20 );
  21
  22 int main () {
  23     char buf[10];
  24     memset(&buf[0], 'A', 9);
  25     buf[9] = 0;
  26     puts(buf);
  27     return 0;
  28 }