This patch enables building gcc-4.6.4 using gcc-2.95.3 and glibc-2.2.5

  * Tweak Makefile to allow overriding NATIVE_SYSTEM_HEADER_DIR using #:makeflags
  * Add missing limits.h include.
  * Add SSIZE_MAX define.  The SSIZE_MAX define has been added to Mes
    upstream and can be removed with the next Mes release.
  * Remove -fbuilding-libgcc flag, it assumes features being present from a
    newer gcc or glibc.
  * [MES_BOOTSTRAP_GCC]: Disable threads harder.

Upstream status: not presented upstream.

diff --git a/gcc/Makefile.in b/gcc/Makefile.in
index f3cc49fdb18..bc5718fc9a6 100644
--- a/gcc/Makefile.in
+++ b/gcc/Makefile.in
@@ -440,7 +440,7 @@ LINKER_PLUGIN_API_H = $(srcdir)/../include/plugin-api.h
 LTO_SYMTAB_H = $(srcdir)/../include/lto-symtab.h
 
 # Default native SYSTEM_HEADER_DIR, to be overridden by targets.
-NATIVE_SYSTEM_HEADER_DIR = /usr/include
+# NATIVE_SYSTEM_HEADER_DIR = /usr/include
 # Default cross SYSTEM_HEADER_DIR, to be overridden by targets.
 CROSS_SYSTEM_HEADER_DIR = @CROSS_SYSTEM_HEADER_DIR@
 
diff --git a/gcc/config/host-linux.c b/gcc/config/host-linux.c
index 94b7a0b89a7..ab2baab55ca 100644
--- a/gcc/config/host-linux.c
+++ b/gcc/config/host-linux.c
@@ -23,6 +23,12 @@
 #include "hosthooks.h"
 #include "hosthooks-def.h"
 
+// ../.././gcc/config/host-linux.c:213: `SSIZE_MAX' undeclared (first
+// use in this function)
+#include <limits.h>
+#ifndef	SSIZE_MAX
+# define SSIZE_MAX	LONG_MAX
+#endif
 
 /* Linux has a feature called exec-shield-randomize that perturbs the
    address of non-fixed mapped segments by a (relatively) small amount.
diff --git a/libgcc/generic-morestack-thread.c b/libgcc/generic-morestack-thread.c
index bbe6dd12b5a..1d1d48223d7 100644
--- a/libgcc/generic-morestack-thread.c
+++ b/libgcc/generic-morestack-thread.c
@@ -34,7 +34,7 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
    will want to define inhibit_libc while building a compiler which
    can build glibc.  */
 
-#ifndef inhibit_libc
+#if 0 //!defined (inhibit_libc) && !MES_BOOTSTRAP_GCC
 
 #include <errno.h>
 #include <pthread.h>
 class='path'>path: <a href='/guix/log/?id=549e0f2fa7f0a19801f6a86c992f1dd48e6b0d0a&amp;showmsg=1'>root</a>/<a href='/guix/log/tests?id=549e0f2fa7f0a19801f6a86c992f1dd48e6b0d0a&amp;showmsg=1'>tests</a>/<a href='/guix/log/tests/graph.scm?id=549e0f2fa7f0a19801f6a86c992f1dd48e6b0d0a&amp;showmsg=1'>graph.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/graph.scm?id=549e0f2fa7f0a19801f6a86c992f1dd48e6b0d0a'>Collapse</a>)</th><th class='left'>Author</th></tr>
<tr class='logheader'><td><span title='2023-08-21 16:16:47 +0200'>2023-08-21</span></td><td class='logsubject'><a href='/guix/commit/tests/graph.scm?id=df2117b8e0e9a35ef8be7f122a783190cafed669'>tests: Adjust 'node-back-edges' test for 'bag' to system-dependent glibc.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
Fixes a regression introduced in
560cb51e7b37e2c6f6fe4b72a3781185c57fdf83, which would lead this test on
x86_64-linux to return a DIFF with two packages, nhc98 and dev86 (both
have #:system "i686-linux" and thus depend on a different glibc object;
why other system-specific packages such as 'wine' aren't reported is
unclear).

* tests/graph.scm ("node-transitive-edges + node-back-edges"): Use
'test-equal'.  Define 'system-specific?' and use it.


</td></tr>
<tr class='logheader'><td><span title='2023-04-07 17:53:37 +0200'>2023-04-07</span></td><td class='logsubject'><a href='/guix/commit/tests/graph.scm?id=acdb42e5d09a504d521d8b632c2c4a66d70f94e4'>gnu: Purge pre-1.3.0 deprecated packages.</a></td><td>Bruno Victal</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* gnu/packages/bioinformatics.scm (deeptools): Remove variable.
* gnu/packages/efi.scm (efi_analyzer): Ditto.
* gnu/packages/guile.scm (guile-2.2/bug-fix, guile-json): Ditto.
* gnu/packages/image.scm (libjpeg): Ditto.
* gnu/packages/kde.scm (kdevplatform): Ditto
* gnu/packages/linphone.scm (linphoneqt): Ditto.
* gnu/packages/maths.scm (blis-sandybridge, blis-haswell, blis-knl): Ditto.
* gnu/packages/mpi.scm (hwloc-2.0): Ditto.
* gnu/packages/music.scm (python-abjad, zlfo): Ditto.
* gnu/packages/perl.scm (perl-base, perl-parent): Ditto.
* gnu/packages/tryton.scm (python-trytond): Ditto.
* gnu/packages/video.scm (gnome-mpv): Ditto.
* tests/graph.scm: Use guile-json-1.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;


</td></tr>
<tr class='logheader'>