This patch provides an update so that nhc98 can be built and works with
a modern C compiler (GCC 11) and libc (glibc 2.33).

diff --git a/Makefile.inc b/Makefile.inc
index 4fbd47a..5bce5c9 100644
--- a/Makefile.inc
+++ b/Makefile.inc
@@ -1,6 +1,10 @@
 ### Configurable variables:
 
-OPT = -O3
+# We want C89 semantics plus C++-style comments and things like the
+# 'setjmp_buf' and 'u_short' types.  More importantly, build with '-O1'
+# only to avoid modern optimizations that break the code.
+OPT = -O1 -std=gnu89 -D_GNU_SOURCE=1
+
 #ARCH = -m32
 ARCH = 
 
diff --git a/script/nhc98heap.c b/script/nhc98heap.c
index 534010e..a30d5cd 100644
--- a/script/nhc98heap.c
+++ b/script/nhc98heap.c
@@ -1,5 +1,6 @@
 #include <stdlib.h>
 #include <stdio.h>
+#include <ctype.h>
 main(int argc, char **argv)
 {
   int prefix = 1;
diff --git a/src/runtime/Kernel/collector.c b/src/runtime/Kernel/collector.c
index b95a273..1f879c5 100644
--- a/src/runtime/Kernel/collector.c
+++ b/src/runtime/Kernel/collector.c
@@ -2,6 +2,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <unistd.h>
 #include "node.h"
 /*#include "newmacros.h"  -- already included in node.h */
 /*#include "runtime.h"    -- already included in node.h */
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<tr><td><span title='2024-09-28 00:20:18 +0200'>2024-09-28</span></td><td><a href='/guix/commit/gnu/packages/genimage.scm?id=b21118a2df0f851832068dd5dc1e0b0706e2e38c'>gnu: genimage: Update to version 18.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/genimage.scm (genimage): Update from 15 to 18.
[arguments]: Disable some tests.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Herman Rimm</td></tr>
<tr><td><span title='2024-08-31 10:42:19 +0200'>2024-08-31</span></td><td><a href='/guix/commit/gnu/packages/genimage.scm?id=5a20752ae55e064d281061e0d899f83bb015d6c1'>gnu: genimage: Import the correct set of modules.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/genimage.scm (genimage) [arguments]
&lt;modules&gt;: Replace %default-gnu-imported-modules with %default-gnu-modules.

Change-Id: I65a2e2b371ae9b6f822ba54d09ba6741e403432b
</span></span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2024-08-31 10:42:16 +0200'>2024-08-31</span></td><td><a href='/guix/commit/gnu/packages/genimage.scm?id=f59df1aa3c104aabff3291f6b8b155fb01aebc06'>build-systems: gnu: Export %default-gnu-imported-modules and %default-gnu-mod...</a><span class='msg-avail'>...<span class='msg-tooltip'>Until now users would have to cargo cult or inspect the private
%default-modules variable of (guix build-systems gnu) to discover which
modules to include when extending the used modules via the #:modules argument.

The renaming was automated via the command:

  $ git grep -l %gnu-build-system-modules
    | xargs sed 's/%gnu-build-system-modules/%default-gnu-imported-modules/' -i

* guix/build-system/gnu.scm (%gnu-build-system-modules): Rename to...
(%default-gnu-imported-modules): ... this.
(%default-modules): Rename to...
(%default-gnu-modules): ... this.  Export.
(dist-package, gnu-build, gnu-cross-build): Adjust accordingly.

Change-Id: Idef307fff13cb76f3182d782b26e1cd3a5c757ee
</span></span></td><td>Maxim Cournoyer</td></tr>