[Bug tree-optimization/85756] New: wrong code at -Os on x86-64-linux-gnu in 32-bit mode

[su at cs dot ucdavis.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85756

            Bug ID: 85756
           Summary: wrong code at -Os on x86-64-linux-gnu in 32-bit mode
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: su at cs dot ucdavis.edu
  Target Milestone: ---

$ gcctk -v
Using built-in specs.
COLLECT_GCC=gcctk
COLLECT_LTO_WRAPPER=/home/su/software/tmp/gcc/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/9.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-source-trunk/configure --enable-languages=c,c++,lto
--prefix=/home/su/software/tmp/gcc/gcc-trunk --disable-bootstrap
Thread model: posix
gcc version 9.0.0 20180511 (experimental) [trunk revision 260178] (GCC) 
$ 
$ gcctk -m32 -O0 small.c; ./a.out
$ 
$ gcctk -m32 -Os small.c
$ ./a.out
Segmentation fault (core dumped)
$ 


-------------------------------------


int printf (const char *, ...);

int a, c, *e, f, h = 10;
short b;
unsigned int p;

void fn1 ()
{
  unsigned j = 1, m = 430523;
  int k, n = 1, *l = &h;
L:
  p = m;
  m = -((~65535U | j) - n);
  f = b << ~(n - 8);
  n = (m || b) ^ f;
  j = p;
  if (p < m)
    *l = k < 3;
  if (!n)
    l = &k;
  if (c)
    {
      printf ("%d", a);
      goto L;
    }
  if (!*l)
    *e = 1;
}

int main ()
{
  fn1 ();
  return 0; 
}