[Bug ada/80007] New: --disable-bootstrap with gnat-5 leads to failed gnat-7 build on aarch64

["tulipawn at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80007

            Bug ID: 80007
           Summary: --disable-bootstrap with gnat-5 leads to failed gnat-7
                    build on aarch64
           Product: gcc
           Version: 7.0.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: ada
          Assignee: unassigned at gcc dot gnu.org
          Reporter: tulipawn at gmail dot com
  Target Milestone: ---

Never tried bootstrapping ada this way before (a full bootstrap succeeded a few
days ago), so I'm not entirely sure if that's allowed/advisable but I got the
following failure:

/mnt/odroid/gcc-master/build/./gcc/xgcc -B/mnt/odroid/gcc-master/build/./gcc/
-B/usr/gcc7/aarch64-linux-gnu/bin/ -B/usr/gcc7/aarch64-linux-gnu/lib/ -isystem
/usr/gcc7/aarch64-linux-gnu/include -isystem
/usr/gcc7/aarch64-linux-gnu/sys-include    -c -g -O2  -fPIC  -W -Wall -gnatpg
-nostdinc   g-exptty.adb -o g-exptty.o
+===========================GNAT BUG DETECTED==============================+
| 7.0.1 20170311 (experimental) (aarch64-linux-gnu) Program_Error unhandled
signal|
| Error detected at s-stoele.adb:36:20                                     |
| Please submit a bug report; see https://gcc.gnu.org/bugs/ .              |
| 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-exptty.adb
g-exptty.ads
g-expect.ads
gnat.ads
g-os_lib.ads
s-os_lib.ads
s-string.ads
ada.ads
a-uncdea.ads
g-regpat.ads
s-regpat.ads
g-tty.ads
s-oscons.ads
interfac.ads
i-c.ads
s-parame.ads
s-exctab.ads
s-stalib.ads
a-unccon.ads
a-tags.ads
s-stoele.ads
a-stream.ads
s-soflin.ads
a-except.ads
s-traent.ads
s-stache.ads
s-stratt.ads
s-unstyp.ads
s-secsta.ads
s-finmas.ads
a-finali.ads
s-finroo.ads
s-stopoo.ads
s-pooglo.ads
a-caldel.ads
a-calend.ads
s-stoele.adb

compilation abandoned
../gcc-interface/Makefile:296: recipe for target 'g-exptty.o' failed