[Bug middle-end/80692] _Decimal64 -0 != 0 unless optimization is turned off

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80692

--- Comment #3 from Segher Boessenkool <segher at gcc dot gnu.org> ---
Author: segher
Date: Wed May 17 21:57:23 2017
New Revision: 248174

URL: https://gcc.gnu.org/viewcvs?rev=248174&root=gcc&view=rev
Log:
Fix comparison of decimal float zeroes (PR80692)

Decimal float negative zero should compare equal to positive zero.
Decimal float zeroes are encoded as value class "normal" (in real.c);
they need to be handled specially, but in this one case that does not
yet happen.  This fixes it.


        PR middle-end/80692
        * real.c (do_compare): Give decimal_do_compare preference over
        comparing just the signs.

gcc/testsuite/
        PR middle-end/80692
        * gcc.c-torture/execute/pr80692.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.c-torture/execute/pr80692.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/real.c
    trunk/gcc/testsuite/ChangeLog