[Bug tree-optimization/55011] [4.8 Regression] GCC in an infinite loop at -O2 in VRP

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55011

--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> 2012-10-22 13:26:52 UTC ---
Author: rguenth
Date: Mon Oct 22 13:26:48 2012
New Revision: 192689

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=192689
Log:
2012-10-22  Richard Biener  <rguenther@suse.de>

    PR tree-optimization/55011
    * tree-vrp.c (update_value_range): For invalid lattice transitions
    drop to VARYING.

    * gcc.dg/torture/pr55011.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/torture/pr55011.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-vrp.c