[Bug tree-optimization/56486] New: infinite loop in cc1 at -O1 and above

["dhazeghi at yahoo dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56486

             Bug #: 56486
           Summary: infinite loop in cc1 at -O1 and above
    Classification: Unclassified
           Product: gcc
           Version: 4.7.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: dhazeghi@yahoo.com


The following code (generated by csmith) causes gcc 4.6.3 and 4.7.2 to go into
an infinite loop when compiled at -O1 or higher.  This does not occur with
current trunk or gcc 4.5.4 (although 4.5.4 does take about 10 seconds to
compile it), so technically this is a regression on 4.6 and 4.7.

An attempt to use creduce to reduce it failed as end-result no longer hangs (it
does take 10 seconds to compile though).

$ gcc-4.7 --version
gcc-4.7 (GCC) 4.7.2
$ gcc-4.5 -O1 crash.i
$ gcc-trunk -O1 crash.i
$ gcc-4.7 -O1 crash.i
<hangs>