Bug in GCC

["Jarek Pelczar" <jarekp3 at wp dot pl>]

I use GCC from DJGPP.

gcc -v dump:

Reading specs from c:/djgpp/lib/gcc-lib/djgpp/3.21/specs
Configured with: /devel/gnu/gcc/3.2/gnu/gcc-3.21/configure i586-pc-msdosdjgpp --prefix=/dev/env/DJDIR --disable-nls
Thread model: single
gcc version 3.2.1

When I try to comiple such program:

/* ------------------------------ CUT ------------------------------ */

 

#define TASK_MEMORY_START  0x1000000
#define MAX_TASK_MEMORY   (512<<12) /* Max 512MB */

 

static unsigned long TASK_MEMORY_BEGIN,TASK_MEMORY_END;

 

unsigned long * mem_map;
unsigned long * kernel_pgdir=(unsigned long *)0x70000;
unsigned long * kernel_pgtables;

 

#define mm_copy_page(dst,src) \
    __asm__("cld;rep;movsl"::"S"(src),"D"(dst),"c"(1024))

 

#define schedule() __asm__("call change_task");
   
void mm_boot_log(char * str)
{
 __asm__("call boot_log"::"S"(str));
}
 
void mm_panic(char * str)
{
 mm_boot_log(str);
 for(;;);
}

 

void mm_memory_avail_scan(void)
{
 register int i;
 volatile unsigned long * p;
 TASK_MEMORY_BEGIN=TASK_MEMORY_START;
 p=(volatile unsigned long *)(TASK_MEMORY_BEGIN);
 for(i=TASK_MEMORY_BEGIN;i<MAX_TASK_MEMORY;i+=1024,p+=1024)
 {
  *p=0x1BADB002;
  if((*p)!=0x1BADB002) break;
 }
 TASK_MEMORY_END=i;
}

 

/* ------------------------------ CUT ------------------------------ */

 

I call:

gcc test.c -S -o test.s -O2 -fomit-frame-pointer

 

And I get invalid output file which contains (part of, only for mm_memory_avail_scan())

 

/* ------------------------------ CUT ------------------------------ */

 

.globl _mm_memory_avail_scan
_mm_memory_avail_scan:
 movl $16777216, _TASK_MEMORY_BEGIN
 movl $16777216, _TASK_MEMORY_END
 ret

 

/* ------------------------------ CUT ------------------------------ */

 

Attachment: smime.p7s
Description: application/pkcs7-signature