[Bug tree-optimization/50873] New: The fix to PR50730 causes gcc.c-torture/unsorted/dilayout.c to ICE

["mgretton at sourceware dot org" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50873

             Bug #: 50873
           Summary: The fix to PR50730 causes
                    gcc.c-torture/unsorted/dilayout.c to ICE
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: mgretton@sourceware.org
                CC: irar@il.ibm.com
            Target: arm*-*-*


The fix to PR50730 (revision 180367 -
http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=180367) causes the test
gcc.c-torture/unsorted/dilayout.c to ICE at -O3.

A reduced test case is:

$ cat test.c
/* arm-none-eabi-gcc -mcpu=cortex-a9 -mfpu=neon -mfloat-abi=soft -O3 test.c  */
struct ii
{
  int a;
  int b;
};
struct foo
{
  int a;
  struct ii ab;
};
struct ii
foo (int *p, struct foo a)
{
  p[0] = a.a;
  p[1] = a.ab.a;
}
/* end of test.c.  */
$ arm-none-eabi-gcc -mcpu=cortex-a9 -mfpu=neon -mfloat-abi=soft -O3 test.c
test.c: In function 'foo':
test.c:15:11: internal compiler error: in expand_insn, at optabs.c:7693

-fno-tree-vectorize causes the issue to go away.

The issue still exists in revision 180524