[Bug ada/65519] New: Unable to coalesce ssa_names 2 and 87 which are marked as MUST COALESCE if ZCX_By_Default is set False

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65519

            Bug ID: 65519
           Summary: Unable to coalesce ssa_names 2 and 87 which are marked
                    as MUST COALESCE if ZCX_By_Default is set False
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: ada
          Assignee: unassigned at gcc dot gnu.org
          Reporter: syq at debian dot org

Created attachment 35101
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35101&action=edit
the required files

/home/syq/gcctest/gcc-5-5-20150321/build/./gcc/xgcc
-B/home/syq/gcctest/gcc-5-5-20150321/build/./gcc/ -B/usr/x86_64-linux-gnu/bin/
-B/usr/x86_64-linux-gnu/lib/ -isystem /usr/x86_64-linux-gnu/include -isystem
/usr/x86_64-linux-gnu/sys-include -isystem
/home/syq/gcctest/gcc-5-5-20150321/build/sys-include    -c -g -O2   -W -Wall
-gnatpg -gnata -nostdinc   g-sptavs.ads -o g-sptavs.o

Unable to coalesce ssa_names 2 and 87 which are marked as MUST COALESCE.
I.3_2(ab) and  I.3_87(ab)
+===========================GNAT BUG DETECTED==============================+
| 5.0.0 20150321 (experimental) [trunk revision 221551] (x86_64-linux-gnu) GCC
error:|
| SSA corruption                                                           |
| Error detected around g-spitbo.ads:373:12                                |
| Please submit a bug report; see http://gcc.gnu.org/bugs.html.            |
| Use a subject line meaningful to you and us to track the bug.            |
| Include the entire contents of this bug box in the report.               |
| Include the exact command that you entered.                              |
| Also include sources listed below.                                       |
+==========================================================================+

Please include these source files with error report
Note that list may not be accurate in some cases,
so please double check that the problem can still
be reproduced with the set of files listed.
Consider also -gnatd.n switch (see debug.adb).

system.ads
g-sptavs.ads
g-spitbo.ads
gnat.ads
ada.ads
a-finali.ads
s-finroo.ads
a-string.ads
a-strunb.ads
a-strmap.ads
a-charac.ads
a-chlat1.ads
s-atocou.ads
interfac.ads
a-tags.ads
s-stoele.ads
s-stalib.ads
a-unccon.ads
s-exctab.ads
a-stream.ads
s-soflin.ads
a-except.ads
s-parame.ads
s-traent.ads
s-stache.ads
s-unstyp.ads
s-stratt.ads
s-secsta.ads
s-stposu.ads
s-stopoo.ads
s-finmas.ads
s-pooglo.ads
s-ststop.ads
s-string.ads
a-uncdea.ads
g-spitbo.adb
a-stunau.ads
g-debuti.ads
g-io.ads
s-strhas.ads
s-valint.ads
s-strhas.adb
s-stalib.adb
s-memory.ads
s-stoele.adb


raised TYPES.UNRECOVERABLE_ERROR : comperr.adb:423
../gcc-interface/Makefile:311: recipe for target 'g-sptavs.o' failed


I can reproduce it on mips64el and amd64.