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[Bug middle-end/58419] New: wrong code at -O3 on x86_64-linux-gnu in 32-bit mode


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58419

            Bug ID: 58419
           Summary: wrong code at -O3 on x86_64-linux-gnu in 32-bit mode
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: su at cs dot ucdavis.edu

The current gcc trunk mis-compiles the following code on x86_64-linux at -O3 in
32-bit mode. 

This is a regression from 4.8.x. 


$ gcc-trunk -v
Using built-in specs.
COLLECT_GCC=gcc-trunk
COLLECT_LTO_WRAPPER=/usr/local/gcc-trunk/libexec/gcc/x86_64-unknown-linux-gnu/4.9.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc-trunk/configure
--enable-languages=c,c++,objc,obj-c++,fortran,lto
--with-gmp=/usr/local/gcc-trunk --with-mpfr=/usr/local/gcc-trunk
--with-mpc=/usr/local/gcc-trunk --with-cloog=/usr/local/gcc-trunk
--prefix=/usr/local/gcc-trunk
Thread model: posix
gcc version 4.9.0 20130913 (experimental) [trunk revision 202556] (GCC) 
$ gcc-trunk -m32 -O2 small.c
$ a.out
0
$ gcc-4.8 -m32 -O3 small.c
$ a.out
0
$ gcc-trunk -m64 -O3 small.c
$ a.out
0
$ gcc-trunk -m32 -O3 small.c
$ a.out
Segmentation fault (core dumped)
$ 


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

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

int a, g, i, k, *p; 
char b, e;
short c, h;
static short *d = &c;

char
foo (int p1, int p2)
{
  return p1 - p2;
}

int
bar ()
{
  short *q = &c;
  *q = 1;
  *p = 0;
  return 0;
}

int
main ()
{
  for (b = -22; b >= -29; b--)
    {
      short *l = &h;
      char *m = &e;
      *l = a;
      g = foo (*m = k && *d, 1 > i) || bar (); 
    }
  printf("0\n");
  return 0;
}


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