Hi,
when compiling the appended C-code first with
gcc -v -save-temps bug.c
and then with
gcc -v -save-temps -O bug.c
you will see garbage at the end of the output of the
optimized case.

Best regards
Willi N|_er, LinuxLab SAP AG


*********************************************
****** bug.c ********************************
*********************************************

#include <stdio.h>
#include <stdlib.h>

/*#define TRAILER 0x07*/
#define TRAILER 'A'


static char buf[40];
static char line[30] = "1234567890123456789012345678*";

static void f()
{
  char trailer[2] = { TRAILER, 0x00 };
  char* const last = buf + sizeof(line) - 2;
  memcpy(buf, line, sizeof(line));
  if (*last == '*')
  {
    memcpy(last, trailer, 2);
  }
}

int main()
{
  f();
  printf("%s\n", buf);
  return 0;
}

**************************************************
****** end of bug.c ******************************
**************************************************