Fix a regression in glibc 2.27 when built without ldconfig.  See
<https://sourceware.org/bugzilla/show_bug.cgi?id=22977> for details.

diff --git a/include/libc-symbols.h b/include/libc-symbols.h
index 6137304b0b..7d630f36d8 100644
--- a/include/libc-symbols.h
+++ b/include/libc-symbols.h
@@ -508,7 +508,7 @@ for linking")
 # ifndef __ASSEMBLER__
 #  if !defined SHARED && IS_IN (libc) && !defined LIBC_NONSHARED \
       && (!defined PIC || !defined NO_HIDDEN_EXTERN_FUNC_IN_PIE) \
-      && !defined NO_HIDDEN
+      && !defined NO_HIDDEN && defined USE_LDCONFIG
 #   define __hidden_proto_hiddenattr(attrs...) \
   __attribute__ ((visibility ("hidden"), ##attrs))
 #   define hidden_proto(name, attrs...) \
='koszko' selected='selected'>koszko</option>
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<div class='path'>path: <a href='/guix/log/?id=369d0e7f5c7d5b81543bc053ea9a51fd921102ec'>root</a>/<a href='/guix/log/build-aux?id=369d0e7f5c7d5b81543bc053ea9a51fd921102ec'>build-aux</a>/<a href='/guix/log/build-aux/cuirass?id=369d0e7f5c7d5b81543bc053ea9a51fd921102ec'>cuirass</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/build-aux/cuirass?id=369d0e7f5c7d5b81543bc053ea9a51fd921102ec&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2021-03-10 08:49:48 +0100'>2021-03-10</span></td><td><a href='/guix/commit/build-aux/cuirass?id=76bea3f8bcd951ded88dfb7f8cad5bc3e5a1701f'>ci: Remove hydra support.</a><span class='msg-avail'>...<span class='msg-tooltip'>This removes hydra support to use Cuirass as the only continuous integration
system.

* build-aux/hydra/gnu-system.scm: Remove it.
* build-aux/hydra/guix-modular.scm: Ditto.
* build-aux/hydra/guix.scm: Ditto.
* build-aux/cuirass/hydra-to-cuirass.scm: Ditto.
* Makefile.am (EXTRA_DIST): Update it.
(hydra-jobs.scm): Remove it.
(cuirass-jobs.scm): Update it.
* build-aux/hydra/evaluate.scm: Move it to ...
* build-aux/cuirass/evaluate.scm: ... here.
* build-aux/cuirass/guix-modular.scm: Remove it.
* build-aux/cuirass/gnu-system.scm: Ditto.
* guix/packages.scm (%hydra-supported-systems): Rename it to ...
(%cuirass-supported-systems): ... this variable.
* build-aux/check-final-inputs-self-contained: Adapt it.
* etc/release-manifest.scm: Ditto.
* gnu/ci.scm (package-&gt;alist): Remove it.
(derivation-&gt;job): New procedure.
(package-job, package-cross-job, cross-jobs, image-jobs, system-test-jobs,
tarball-jobs): Use it.
(guix-jobs): New procedure.
(hydra-jobs): Rename it to ...
(cuirass-jobs): ... this procedure.
</span></span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-10-04 14:04:14 +0200'>2020-10-04</span></td><td><a href='/guix/commit/build-aux/cuirass?id=fdbf8a7a75e9d63957ea6d8a63181aa131edeaea'>cuirass: Add hurd-manifest.</a><span class='msg-avail'>...<span class='msg-tooltip'>* build-aux/cuirass/hurd-manifest.scm: New file.
</span></span></td><td>Jan (janneke) Nieuwenhuizen</td></tr>