Disable -Werror=nonnull on getcwd(0, 4096) because GCC incorrectly warns that
the second argument should be NULL with recent glibc.  See:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96832
https://sourceware.org/bugzilla/show_bug.cgi?id=26545

diff --git a/nss/coreconf/nsinstall/nsinstall.c b/nss/coreconf/nsinstall/nsinstall.c
--- a/nss/coreconf/nsinstall/nsinstall.c
+++ b/nss/coreconf/nsinstall/nsinstall.c
@@ -236,14 +236,20 @@ main(int argc, char **argv)
 	return 0;
 
     if (!cwd) {
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wnonnull"
 	cwd = GETCWD(0, PATH_MAX);
+#pragma GCC diagnostic pop
 	if (!cwd)
 	    fail("could not get CWD");
     }
 
     /* make sure we can get into todir. */
     xchdir(todir);
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wnonnull"
     todir = GETCWD(0, PATH_MAX);
+#pragma GCC diagnostic pop
     if (!todir)
 	fail("could not get CWD in todir");
     tdlen = strlen(todir);
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<tr><td><span title='2023-04-21 00:44:08 -0400'>2023-04-21</span></td><td><a href='/guix/commit/gnu/packages/rpm.scm?id=aee7fc2e41059e81050087deb0573b99ca868b95'>gnu: libmodulemd: Remove fix-docbook-references phase.</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2022-08-02 15:10:01 -0400'>2022-08-02</span></td><td><a href='/guix/commit/gnu/packages/rpm.scm?id=1a5384e9a702c366f3b14ed1ac3db8d3eb6640e2'>gnu: createrepo-c: Update to 0.20.1.</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2022-08-02 15:10:01 -0400'>2022-08-02</span></td><td><a href='/guix/commit/gnu/packages/rpm.scm?id=da96de3b661723954a6469b70d9cb9cc00e031b3'>gnu: drpm: Update to 0.5.1.</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2022-08-02 15:10:01 -0400'>2022-08-02</span></td><td><a href='/guix/commit/gnu/packages/rpm.scm?id=c162dc379ccbfebcd15ae98791ce4e68249322b7'>gnu: createrepo-c: Use gexps.</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2022-08-02 15:10:00 -0400'>2022-08-02</span></td><td><a href='/guix/commit/gnu/packages/rpm.scm?id=5ee30cfa84a7d66cab5803c334e81579f6797200'>gnu: libmodulemd: Fix build and use new style inputs and gexps.</a><span class='msg-avail'>...</span></td><td>Maxim Cournoyer</td></tr>