[Bug c/21718] New: real.c rounding not perfect

["neil at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

When compiled with -Wall,

int foo (void) { if (9007199254740991.4999999999999999999999999999999995 ==
9007199254740991.5) return 1;}

does not complain about a missing return statement, showing that GCC is folding
the comparison to true.  However, the LHS should round down.

With one less 9 GCC gets it correct.

I'm not convinced it's worthwhile to get perfect rounding, but Joseph wanted me
to file a report.

-- 
           Summary: real.c rounding not perfect
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: neil at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21718