Current mainline GCC gets an ICE in check_loop_closed_ssa_use building
any of ten benchmark programs from SPEC CPU2000 on powerpc-linux using
the options "-O2 -ftree-vectorize -maltivec -fprofile-generate".  This
minimized test case demonstrates the problem:
                                                                                
static int a[27];
void
foo (void)
{
   int i;
   for (i = 0; i < 27; i++)
      a[i] = 0;
}
                                                                                
elm3b11% /opt/gcc-nightly/mline/bin/gcc -O2 -ftree-vectorize -maltivec
-fprofile-generate -c bug.c
bug.c: In function ‘foo’:
bug.c:4: internal compiler error: in check_loop_closed_ssa_use, at
tree-ssa-loop-manip.c:394
                                                                                
Not that the information is useful, but the test starts failing on
mainline with the merge from tree-cleanup-branch on 2005-04-09, and it
started failing on the branch with a merge from mainline on 2005-04-01.