[Bug tree-optimization/60733] ICE by LTO on valid code at -O3 on x86_64-linux-gnu

[su at cs dot ucdavis.edu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60733

--- Comment #1 from Zhendong Su <su at cs dot ucdavis.edu> ---
Here is a variant that causes an ICE even without LTO. 

$ 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 --prefix=/usr/local/gcc-trunk
--enable-languages=c,c++ --disable-werror --enable-multilib
Thread model: posix
gcc version 4.9.0 20140401 (experimental) [trunk revision 208971] (GCC) 
$ 
$ gcc-4.8 -O3 small2.c; a.out
$ 
$ gcc-trunk -O3 small2.c 
small2.c: In function ‘main’:
small2.c:11:1: error: definition in block 12 follows the use
 main ()
 ^
for SSA_NAME: _64 in statement:
slsr_125 = _64 * 65535;
small2.c:11:1: internal compiler error: verify_ssa failed
0xb0b64b verify_ssa(bool)
    ../../gcc-trunk/gcc/tree-ssa.c:1096
0x8ae43c execute_function_todo
    ../../gcc-trunk/gcc/passes.c:1854
0x8aed93 execute_todo
    ../../gcc-trunk/gcc/passes.c:1887
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.
$   


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


int a, d, e, f, g, h, i, j, k;
unsigned short b;

short
fn1 (int p1, int p2)
{
  return p1 * p2;
}

int
main ()
{
  for (; a; a--)
    {
      int l = 0;
      if (f >= 0)
    {
      for (; h;)
        e = 0;
      for (; l != -6; l--)
        {
          j = fn1 (b--, d);
          for (g = 0; g; g = 1)
        ;
          k = e ? 2 : 0;
        }
      i = 0;
      for (;;)
        ;
    }
    }
  d = 0;
  return 0;
}