Skip a GC test known to be flaky:

  https://issues.guix.gnu.org/issue/37425
  https://github.com/golang/go/issues/27636

--- go/src/runtime/gc_test.go	2019-09-16 23:10:18.200680387 +0200
+++ go/src/runtime/gc_test.go	2019-09-16 23:11:50.324360646 +0200
@@ -27,6 +27,9 @@ func TestGcSys(t *testing.T) {
 	if runtime.GOOS == "linux" && runtime.GOARCH == "arm64" {
 		t.Skip("skipping test; GOOS=linux GOARCH=arm64 https://github.com/golang/go/issues/27636")
 	}
+	if runtime.GOOS == "linux" {
+		t.Skip("skipping test; GOOS=linux https://issues.guix.gnu.org/issue/37425")
+	}
 	got := runTestProg(t, "testprog", "GCSys")
 	want := "OK\n"
 	if got != want {
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<tr><td><span title='2017-12-07 20:42:48 -0500'>2017-12-07</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=475a28bd1d9dc787b03f212ae5eeb4e74594fc0d'>gnu: mpd: Update to 0.20.12.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2017-11-17 22:36:26 +0100'>2017-11-17</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=ac257f127ac5e1fd4758d3a05e4a19fde3af4e01'>gnu: Move testing packages from python.scm to check.scm.</a><span class='msg-avail'>...</span></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2017-10-31 18:13:53 -0400'>2017-10-31</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=bc8bd40e6ac082aa301065f80b06c9f203092ce3'>gnu: ncmpcpp: Update to 0.8.1.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2017-10-30 21:46:14 -0400'>2017-10-30</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=3022680abaae5713b6c0cb27b1580faf48e41439'>gnu: mpd: Update to 0.20.11.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2017-09-04 11:19:23 -0400'>2017-09-04</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=6cdb0f4d12dfd0c458655958862c8396bb6397d9'>gnu: mpd: Update to 0.20.10.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2017-07-10 16:59:50 -0400'>2017-07-10</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=a708fea4061a2b4ada5aaaaff44c74848d095409'>gnu: ncmpcpp: Update to 0.8.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2017-06-21 15:15:07 -0400'>2017-06-21</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=7641266b0328f8a3a4f3643560d00dcf82d539b3'>gnu: mpd: Build with the default GCC.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2017-06-17 00:06:38 -0400'>2017-06-17</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=2bada0b300bc8ffc8e86b2e8c71af1438651d5d9'>gnu: mpd: Update to 0.20.9.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2017-04-14 12:53:33 -0400'>2017-04-14</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=2f64f4444a81e9b2d75b2de3f1fc4c71e099b214'>gnu: ncmpc: Update to 0.27.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2017-04-14 12:53:33 -0400'>2017-04-14</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=ed8a6c13847d3d942e6f7083f60f87a7daa21331'>gnu: libmpdclient: Update to 2.11.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2017-03-19 21:55:09 -0400'>2017-03-19</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=0420e8968240c9e12acc5fa69373f1ff5110ee99'>gnu: mpd: Update to 0.20.6.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2017-02-12 10:26:01 -0500'>2017-02-12</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=6ea86d7ec38f8c23957d6cce9ec6528987953ef8'>gnu: mpd: Update to 0.20.4.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2016-12-29 17:28:34 -0500'>2016-12-29</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=87b52095584ccd2ff50f8abd2c585ea3650ece1c'>gnu: mpd: Install systemd service files.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2016-12-29 11:30:31 -0500'>2016-12-29</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=d835c6cc4bc343810ec223be3d9879830e782428'>gnu: mpd: Update to 0.19.21.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2016-11-25 11:20:21 -0500'>2016-11-25</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=de32aa74b4f7762e887e80047804c42d495ab841'>Merge branch 'master' into python-build-system</a></td><td>Leo Famulari</td></tr>
<tr><td><span title='2016-11-21 19:47:30 +0300'>2016-11-21</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=7c90d0f40e822cfd4b690329ad0452e59cb11863'>gnu: packages: Use gettext-minimal.</a><span class='msg-avail'>...</span></td><td>Alex Kost</td></tr>
<tr><td><span title='2016-11-16 13:09:36 -0500'>2016-11-16</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=1d87fdf531d891a5fe2ea934104dc367ac226b58'>gnu: ncmpcpp: Update to 0.7.7.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2016-11-15 22:28:59 +0100'>2016-11-15</span></td><td><a href='/guix/commit/gnu/packages/mpd.scm?id=5c31f4aa7c11fcf720c0ce0e26d55788e2df1044'>gnu: Remove python-setuptools and python2-setuptools from inputs (part 4a)</a><span class='msg-avail'>...</span></td><td>Hartmut Goebel</td></tr>