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);
>Wojtek's customized Guix</td><td class='sub right'></td></tr></table>
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<a href='/guix/about/'>about</a><a href='/guix/'>summary</a><a href='/guix/refs/?id=43d59be5179c6100a982f0098f3d0695acba973b'>refs</a><a class='active' href='/guix/log/README?showmsg=1'>log</a><a href='/guix/tree/README?id=43d59be5179c6100a982f0098f3d0695acba973b'>tree</a><a href='/guix/commit/README?id=43d59be5179c6100a982f0098f3d0695acba973b'>commit</a><a href='/guix/diff/README?id=43d59be5179c6100a982f0098f3d0695acba973b'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/README'>
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<div class='path'>path: <a href='/guix/log/?id=43d59be5179c6100a982f0098f3d0695acba973b&amp;showmsg=1'>root</a>/<a href='/guix/log/README?id=43d59be5179c6100a982f0098f3d0695acba973b&amp;showmsg=1'>README</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/README?id=43d59be5179c6100a982f0098f3d0695acba973b'>Collapse</a>)</th><th class='left'>Author</th></tr>
<tr class='logheader'><td><span title='2021-05-20 01:58:04 +0200'>2021-05-20</span></td><td class='logsubject'><a href='/guix/commit/README?id=c0087d33705f53cc3619a1a43a33602aaecc3a8b'>The #guix channel is hosted by Libera Chat.</a></td><td>Tobias Geerinckx-Rice</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* README (Contact): Update network name.
* ROADMAP: Likewise.
* doc/contributing.texi (Contributing): Likewise.
* doc/guix.texi (After System Installation): Likewise.


</td></tr>
<tr class='logheader'><td><span title='2020-10-23 12:57:20 -0400'>2020-10-23</span></td><td class='logsubject'><a href='/guix/commit/README?id=b5aaa3a4fb985d21e21e2a67f48b52f13ebd4728'>doc: Update README.</a></td><td>Maxim Cournoyer</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* README (Installation): Do not mention installing Guix from Git anymore.
(Building from Git): Add section.


</td></tr>
<tr class='logheader'><td><span title='2020-10-22 22:47:54 -0400'>2020-10-22</span></td><td class='logsubject'><a href='/guix/commit/README?id=503d2bfde08f9bf97bbf430516d2f19faedd4319'>README: Refer to the manual for building from Git.</a></td><td>Maxim Cournoyer</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* README (Installing Guix from Guix): Remove section.
(Installation): For installing from Git, refer to the "Building from Git"
section of the manual and suggest using './pre-inst-env guix pull' rather than
'make install' for installing Guix.


</td></tr>
<tr class='logheader'><td><span title='2020-06-02 18:55:53 +0200'>2020-06-02</span></td><td class='logsubject'><a href='/guix/commit/README?id=c75a80189fc19f6ff8b4c82d1d1801be6763b6d2'>doc: Update README to refer to the manual.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* README (Requirements): Refer to the manual.
(Installation): Update URL of the manual.


</td></tr>