See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86724
Author: Rainer Jung
Date: 2018-07-29

isl 0.20 stopped including other unused header files in their header files.
Therefore,now it's necessary to include the stuff ourselves.
--- .../gcc/graphite.h 2018-01-03 11:03:58.000000000 +0000
+++ .../gcc/graphite.h 2018-07-29 17:42:55.836121000 +0000
@@ -37,6 +37,8 @@
 #include <isl/schedule.h>
 #include <isl/ast_build.h>
 #include <isl/schedule_node.h>
+#include <isl/id.h>
+#include <isl/space.h>

 typedef struct poly_dr *poly_dr_p;
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<tr><td><span title='2023-04-24 15:32:54 +0100'>2023-04-24</span></td><td><a href='/guix/commit/.gitignore?id=23f11afacdfe755ffa514a8cbf93ba1121b9db0d'>Add mumi config.</a><span class='msg-avail'>...</span></td><td>Arun Isaac</td></tr>
<tr><td><span title='2022-07-03 14:12:32 +0200'>2022-07-03</span></td><td><a href='/guix/commit/.gitignore?id=4eaf90470f466b3fdab87f6961cb18bb348d433f'>etc: Add teams.scm.</a><span class='msg-avail'>...</span></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2022-06-05 21:27:53 +0200'>2022-06-05</span></td><td><a href='/guix/commit/.gitignore?id=4d47c2c723927ad4ad4142bd517c6ccc03c27528'>gitignore: Add .DS_Store.</a><span class='msg-avail'>...</span></td><td>Pavel Shlyak</td></tr>
<tr><td><span title='2021-10-16 01:44:34 -0400'>2021-10-16</span></td><td><a href='/guix/commit/.gitignore?id=066b1b8f781c7739f8056b81e20adf0b979614bc'>.gitignore: Ignore more autotools directories.</a><span class='msg-avail'>...</span></td><td>Sarah Morgensen</td></tr>
<tr><td><span title='2021-10-16 01:44:30 -0400'>2021-10-16</span></td><td><a href='/guix/commit/.gitignore?id=a599fcd4b09f3df3d6be66b4e64512e482697a96'>.gitignore: Ignore more temporary test directories.</a><span class='msg-avail'>...</span></td><td>Sarah Morgensen</td></tr>
<tr><td><span title='2021-09-20 14:18:21 +0000'>2021-09-20</span></td><td><a href='/guix/commit/.gitignore?id=5c4fd77097e2cecfd4780e099af7954f86779fe1'>etc: Add systemd files for running ‘guix gc’ periodically</a><span class='msg-avail'>...</span></td><td>Thiago Jung Bauermann</td></tr>
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<tr><td><span title='2023-12-10 01:00:00 +0100'>2023-12-10</span></td><td><a href='/guix/commit/nix?id=d993ed43b2bae8717437aa27d9d33fd223a6411f'>daemon: Sacrifice builders on OOM.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2023-12-11 23:18:53 +0100'>2023-12-11</span></td><td><a href='/guix/commit/nix?id=1e47148f46e31eb99ce8ec7bc12232cf50d0ebec'>daemon: Implement ‘substitute-urls’ RPC.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-12-04 22:26:36 +0100'>2023-12-04</span></td><td><a href='/guix/commit/nix?id=d83d4488da5c3bb65867bffa2b8587a7c7b056cc'>daemon: Simplify “empty status” substitute error message.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-09-24 02:00:00 +0200'>2023-09-24</span></td><td><a href='/guix/commit/nix?id=0500af5556307d0a4c14a23864e9e4bccd2643d7'>Revert "build: Add missing guix-gc.timer file to binary tarball."</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2023-09-26 17:36:58 +0200'>2023-09-26</span></td><td><a href='/guix/commit/nix?id=95f21231352b66f92c466cb30f2258291e854f2f'>daemon: Add “git-download” built-in builder.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-09-09 18:47:35 +0200'>2023-09-09</span></td><td><a href='/guix/commit/nix?id=cd469932758bf2bec1ff9c82aeb373e18730d0c4'>daemon: Fix build with GCC 13.</a><span class='msg-avail'>...</span></td><td>Sören Tempel</td></tr>
<tr><td><span title='2023-08-31 23:31:49 -0400'>2023-08-31</span></td><td><a href='/guix/commit/nix?id=69f6edc1a8596d2cb4c67e0435d35633af6f3cbc'>build: Add missing guix-gc.timer file to binary tarball.</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2023-01-09 17:40:54 +0100'>2023-01-09</span></td><td><a href='/guix/commit/nix?id=407175a1d0e29f45639e7f28a531b3981cd20085'>daemon: Improve error message for wrong hash sizes.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-12-18 01:16:47 +0100'>2022-12-18</span></td><td><a href='/guix/commit/nix?id=2d4d26769d6a3be1b21302b0bb2bd099fd55ccf8'>daemon: Make "opening file" error messages distinguishable.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>