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;
ed'>koszko</option>
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<tr><td><span title='2021-06-10 00:57:00 -0400'>2021-06-10</span></td><td><a href='/guix/commit/gnu/packages/docker.scm?id=e35383a76f0a1d1ba01f4b355d8df4ac341216b3'>gnu: docker: Replace tini by tini-static.</a><span class='msg-avail'>...<span class='msg-tooltip'>The dynamically linked tini could fail in some environments, causing 'docker
run' to exit with the following unhelpful error message:

  standard_init_linux.go:219: exec user process caused: no such file or
  directory

Use the statically linked tini binary instead, which should work everywhere.

* gnu/packages/docker.scm (docker)[phases]{patch-paths}: Replace 'tini' by
'tini-static'.
</span></span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2021-06-10 00:57:00 -0400'>2021-06-10</span></td><td><a href='/guix/commit/gnu/packages/docker.scm?id=352f23f71cdfd2f72a77906551b74f2d13f63688'>gnu: tini: Update to 0.19.0 and provide tini-static.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/docker.scm (tini): Update to 0.19.0.  Remove trailing #t.
[phases]: Remove argument.
[configure-flags]: New argument, to clear the CMAKE_INSTALL_RPATH option.
</span></span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2021-04-02 23:33:42 -0400'>2021-04-02</span></td><td><a href='/guix/commit/gnu/packages/docker.scm?id=7bf82f5ede57c9c5344ddb1d4dcfe694eb306bef'>gnu: containerd: Update to 1.4.4.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/docker.scm (containerd): Update to 1.4.4.  Delete
trailing #t.
[arguments]: Set a MAKE-FLAGS binding.
[phases]{patch-paths}: Patch the reference to 'unpigz'.
{build, install}: Use the MAKE-FLAGS variable.
[inputs]: Add pigz.
* gnu/packages/patches/containerd-test-with-go1.13.patch: Delete file.
* gnu/local.mk (dist_patch_DATA): Un-register it.
</span></span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2021-03-11 04:36:22 +0100'>2021-03-11</span></td><td><a href='/guix/commit/gnu/packages/docker.scm?id=9d74b66de78686e5affaf6d7882becd003d3c49a'>gnu: docker-cli: Fix source hash.</a><span class='msg-avail'>...<span class='msg-tooltip'>This is a follow-up to commit 83cda00bc62d665f05d37d07c78a1c4eab5297f0.

* gnu/packages/docker.scm (docker-cli): Fix source hash caused by cascading
%docker-version variable changes.
</span></span></td><td>Léo Le Bouter</td></tr>
<tr><td><span title='2021-03-10 23:37:52 +0100'>2021-03-10</span></td><td><a href='/guix/commit/gnu/packages/docker.scm?id=9b52ae19b12dc0a0878a1c7012bc79b94876e1ab'>gnu: containerd: Update to 1.3.10 [security fixes].</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/docker.scm (containerd): Update to 1.3.10.
</span></span></td><td>Léo Le Bouter</td></tr>
<tr><td><span title='2021-03-10 23:37:52 +0100'>2021-03-10</span></td><td><a href='/guix/commit/gnu/packages/docker.scm?id=83cda00bc62d665f05d37d07c78a1c4eab5297f0'>gnu: docker: Update to 19.03.15 [security fixes].</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/docker.scm (%docker-version): Bump to 19.03.15.
(docker-libnetwork): Bump to 19.03-1.55e924b.
(docker):
[source]: Set git-reference url to 'https://github.com/moby/moby'.
[arguments]&lt;#:phases&gt;: Modify 'delete-failing-tests phase to delete
'signal_linux_test.go'.
</span></span></td><td>Léo Le Bouter</td></tr>
<tr><td><span title='2021-02-08 03:27:42 +0300'>2021-02-08</span></td><td><a href='/guix/commit/gnu/packages/docker.scm?id=b42bb5ca6c8a1485ad9115b7773e1da0360c76c0'>gnu: docker: Update to 19.03.13.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/docker.scm (docker, docker-cli): Update to 19.03.13.
</span></span></td><td>Oleg Pykhalov</td></tr>