[Bug ada/85010] New: [8 Regression] gnat bootstrap fails in assemble_variable, at varasm.c:2297 (power*, aarch64)

[doko at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85010

            Bug ID: 85010
           Summary: [8 Regression] gnat bootstrap fails in
                    assemble_variable, at varasm.c:2297 (power*, aarch64)
           Product: gcc
           Version: 8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: ada
          Assignee: unassigned at gcc dot gnu.org
          Reporter: doko at gcc dot gnu.org
  Target Milestone: ---

seen with r258670 on various powerpc* targets:

+===========================GNAT BUG DETECTED==============================+
| 8.0.1 20180320 (experimental) [trunk revision 258670] (powerpc-linux-gnu) GCC
error:|
| in assemble_variable, at varasm.c:2297                                   |
| Error detected around ../../src/gcc/ada/libgnat/s-rident.ads:75:16       |
| 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.                                       |
+==========================================================================+


complete build logs at
https://buildd.debian.org/status/fetch.php?pkg=gcc-8&arch=ppc64el&ver=8-20180320-1&stamp=1521529621&raw=0
https://buildd.debian.org/status/fetch.php?pkg=gcc-8&arch=ppc64&ver=8-20180320-1&stamp=1521530331&raw=0
https://buildd.debian.org/status/fetch.php?pkg=gcc-8&arch=powerpc&ver=8-20180320-1&stamp=1521529806&raw=0

powerpc64le configured as

         --enable-languages=c,ada,c++,go,d,fortran,objc,obj-c++
         --prefix=/usr
         --with-gcc-major-version-only
         --program-suffix=-8
         --program-prefix=powerpc64le-linux-gnu-
         --enable-shared
         --enable-linker-build-id
         --libexecdir=/usr/lib
         --without-included-gettext
         --enable-threads=posix
         --libdir=/usr/lib
         --enable-nls
         --with-sysroot=/
         --enable-clocale=gnu
         --enable-libstdcxx-debug
         --enable-libstdcxx-time=yes
         --with-default-libstdcxx-abi=new
         --enable-gnu-unique-object
         --enable-plugin
         --enable-default-pie
         --with-system-zlib
         --disable-libphobos
         --enable-objc-gc=auto
         --enable-secureplt
         --with-cpu=power8
         --enable-targets=powerpcle-linux
         --disable-multilib
         --enable-multiarch
         --disable-werror
         --with-long-double-128
         --enable-checking=release
         --build=powerpc64le-linux-gnu
         --host=powerpc64le-linux-gnu
         --target=powerpc64le-linux-gnu