The moc executable loops through headers on CPLUS_INCLUDE_PATH and stumbles
on the GCC internal _GLIBCXX_VISIBILITY macro.  Tell it to ignore it as it is
not supposed to be looking there to begin with.

Upstream report: https://bugreports.qt.io/browse/QTBUG-83160

diff --git a/src/tools/moc/main.cpp b/src/tools/moc/main.cpp
--- a/src/tools/moc/main.cpp
+++ b/src/tools/moc/main.cpp
@@ -188,6 +188,7 @@ int runMoc(int argc, char **argv)
     dummyVariadicFunctionMacro.arguments += Symbol(0, PP_IDENTIFIER, "__VA_ARGS__");
     pp.macros["__attribute__"] = dummyVariadicFunctionMacro;
     pp.macros["__declspec"] = dummyVariadicFunctionMacro;
+    pp.macros["_GLIBCXX_VISIBILITY"] = dummyVariadicFunctionMacro;
 
     QString filename;
     QString output;
selected='selected'>koszko</option>
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<div class='path'>path: <a href='/guix/log/?id=701bced65e578cb97743c24e7744ee0862ef252d'>root</a>/<a href='/guix/log/gnu?id=701bced65e578cb97743c24e7744ee0862ef252d'>gnu</a>/<a href='/guix/log/gnu/services?id=701bced65e578cb97743c24e7744ee0862ef252d'>services</a>/<a href='/guix/log/gnu/services/security-token.scm?id=701bced65e578cb97743c24e7744ee0862ef252d'>security-token.scm</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/gnu/services/security-token.scm?id=701bced65e578cb97743c24e7744ee0862ef252d&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2023-12-22 00:31:41 +0100'>2023-12-22</span></td><td><a href='/guix/commit/gnu/services/security-token.scm?id=3d6583727ec90732ad7bd97808fd4fca8f6d8bdc'>services: Remove unnecessary references to (gnu build shepherd).</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/databases.scm (memcached-shepherd-service): Remove
‘with-imported-modules’ form and ‘modules’ field.
* gnu/services/security-token.scm (pcscd-shepherd-service): Remove
‘with-imported-modules’ form.
* gnu/services/web.scm (hpcguix-web-shepherd-service): Likewise.

Change-Id: Ieb817508f1751e0c1ff551a0e078789a4a813c1c
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-06-25 01:43:08 +0530'>2022-06-25</span></td><td><a href='/guix/commit/gnu/services/security-token.scm?id=037bfd85458dd0b32a6dd85b7c12e85e3dd716ae'>services: pcscd: Use switch-symlinks from (guix build utils).</a><span class='msg-avail'>...<span class='msg-tooltip'>switch-symlinks has been moved to (guix build utils). We need not duplicate it
anymore.

* gnu/services/security-token.scm (pcscd-activation): Use switch-symlinks
from (guix build utils).
</span></span></td><td>Arun Isaac</td></tr>
<tr><td><span title='2021-07-03 20:13:42 +0200'>2021-07-03</span></td><td><a href='/guix/commit/gnu/services/security-token.scm?id=e789ce538ed848bacb8f4eb5742f78b965ccf57c'>services: pcscd: Fix daemon signal handling.</a><span class='msg-avail'>...<span class='msg-tooltip'>"pcscd" wouldn't handle SIGTERM as it inherit ignoring this signal (and
others) from its parent shepherd; fork+exec-command restore signal
handling.  Fixes &lt;https://issues.guix.gnu.org/45202&gt;.

* gnu/services/security-token.scm (pcscd)[start]: Use
fork+exec-command to start "pcscd".
</span></span></td><td>Brice Waegeneire</td></tr>
<tr><td><span title='2021-06-19 23:49:18 +0200'>2021-06-19</span></td><td><a href='/guix/commit/gnu/services/security-token.scm?id=4bed8486d4c0a4ff142903b8bc1584ce84767355'>services: pcscd: Cleanup socket when started.</a><span class='msg-avail'>...<span class='msg-tooltip'>Otherwise when pcscd doesn't terminate properly (ie. receive a SIGKILL),
it won't start again because of it's socket already existing.

* gnu/services/security-token.scm (pcscd-shepherd-service)[start]:
Remove existing socket file.
</span></span></td><td>Brice Waegeneire</td></tr>