[regehr@gamow tmp407]$ current-gcc -c -O3 small.c
small.c: In function 'int161':
small.c:19:1: internal compiler error: in vect_create_epilog_for_reduction, at tree-vect-loop.c:3451
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

[regehr@gamow tmp407]$ current-gcc -v

Using built-in specs.
COLLECT_GCC=current-gcc
COLLECT_LTO_WRAPPER=/uusoc/exports/scratch/regehr/z/compiler-install/gcc-r158618-install/bin/../libexec/gcc/x86_64-unknown-linux-gnu/4.6.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../configure --with-libelf=/usr/local --enable-lto --prefix=/home/regehr/z/compiler-install/gcc-r158618-install --program-prefix=r158618- --enable-languages=c,c++
Thread model: posix
gcc version 4.6.0 20100421 (experimental) (GCC) 

[regehr@gamow tmp407]$ cat small.c

typedef short int int16_t;
typedef int int32_t;
typedef unsigned short int uint16_t;
typedef unsigned int uint32_t;
static int16_t
safe_rshift_func_int16_t_s_u (int16_t left, unsigned int right)
{
  return left || right >= 1 * 8 ? left : left >> right;
}

static uint32_t
safe_add_func_uint32_t_u_u (uint32_t ui1, uint16_t ui2)
{
  return ui1 + ui2;
}

int16_t g_4;
uint32_t g_9[1];
int161 (void)
{
  int32_t l_2;
  for (l_2 = -25; l_2; l_2 = safe_add_func_uint32_t_u_u (l_2, 1))
    g_9[0] ^= safe_rshift_func_int16_t_s_u (g_4, 1);
  return 0;
}