[Bug c/48228] incorrect signed overflow warning when only 0 and 1 are used

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48228

--- Comment #4 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-22 12:40:16 UTC ---
Author: rguenth
Date: Tue Mar 22 12:40:09 2011
New Revision: 171287

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=171287
Log:
2011-03-22  Richard Guenther  <rguenther@suse.de>

    PR tree-optimization/48228
    * tree-vrp.c (vrp_visit_phi_node): Do not stop propagating
    for single-arg PHIs.

    * gcc.dg/Wstrict-overflow-23.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/Wstrict-overflow-23.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-vrp.c