[Bug libstdc++/22200] New: numeric_limits<signed>::is_modulo is inconsistend with gcc

["veksler at il dot ibm dot com" <gcc-bugzilla at gcc dot gnu dot org>]

GCC does not have a proper modulo overflow semantics for signed
integral types.
1. The loop optimizer seems to assume that signed overflow does
   not happen (or is undefined). 
2. On x86 INT_MAX/-1 seems to trap (instead of implementing
   modulo semantics).

In that case numeric_limits<signed>:is_modulo should be synchronized
with gcc and be set to false instead of true.

Another option, is to change gcc to fully support the modulo
arithmetics of signed integer.

-- 
           Summary: numeric_limits<signed>::is_modulo is inconsistend with
                    gcc
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: libstdc++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: veksler at il dot ibm dot com
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22200