The Clar test framework has a bug whereby it skips the parsing phase
on files with mtime=0.

Reported upstream at <https://github.com/vmg/clar/pull/78>.

diff --git a/tests/generate.py b/tests/generate.py
index b639c8f..111ca41 100644
--- a/tests/generate.py
+++ b/tests/generate.py
@@ -63,3 +63,3 @@ class Module(object):
 
-        self.mtime = 0
+        self.mtime = None # Guix sets all file mtimes to '0'
         self.enabled = True
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<tr><td><span title='2019-05-06 23:21:33 +0200'>2019-05-06</span></td><td><a href='/guix/commit/m4/guix.m4?id=fea338c6ca1922097fa233be85f424c152a4f507'>Add (guix lzlib).</a><span class='msg-avail'>...</span></td><td>Pierre Neidhardt</td></tr>
<tr><td><span title='2018-11-23 15:42:00 +0100'>2018-11-23</span></td><td><a href='/guix/commit/m4/guix.m4?id=60e1c1099fc3d73ed7d3235e71aae5d00ab7d773'>Update Guile-SQLite3 URL everywhere.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-09-04 17:25:11 +0200'>2018-09-04</span></td><td><a href='/guix/commit/m4/guix.m4?id=ca719424455465fca4b872c371daf2a46de88b33'>Switch to Guile-Gcrypt.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-06-01 15:35:15 +0200'>2018-06-01</span></td><td><a href='/guix/commit/m4/guix.m4?id=d59e75f3b5b82692bd250a1a3a9965397bb588c5'>build: Check for Guile-SQLite3.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-02-26 18:19:34 +0100'>2018-02-26</span></td><td><a href='/guix/commit/m4/guix.m4?id=1d84d7bf6052c0c80bd212d4524876576e9817d4'>build: Require Guile &gt;= 2.0.13.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-01-06 14:45:01 +0100'>2018-01-06</span></td><td><a href='/guix/commit/m4/guix.m4?id=142182514b84ee233bc27e574df2ca2074291525'>build: Detect broken 'equal?' in Guile 2.2.1.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2017-06-30 00:16:50 +0200'>2017-06-30</span></td><td><a href='/guix/commit/m4/guix.m4?id=1d97fd8cb60f0b5f386f834940f859ff0b0bcc71'>build: Remove check for broken (srfi srfi-37).</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2017-02-20 12:58:07 +0200'>2017-02-20</span></td><td><a href='/guix/commit/m4/guix.m4?id=3b88f3767d9f3ad2cc64173525cd53d429bfe7e7'>gnu: Add bootstrap-binaries for 'aarch64-linux'.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2016-11-25 23:44:20 +0100'>2016-11-25</span></td><td><a href='/guix/commit/m4/guix.m4?id=21531add3205e400707c8fbfd841845f9a71863a'>offload: Use Guile-SSH instead of GNU lsh.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2016-08-10 15:40:22 -0400'>2016-08-10</span></td><td><a href='/guix/commit/m4/guix.m4?id=4ed40a3e6ca030573ded52233bd9e72dcdb85697'>build: Correctly determine the system type for GNU/Hurd systems.</a><span class='msg-avail'>...</span></td><td>Manolis Ragkousis</td></tr>
<tr><td><span title='2016-07-20 11:42:17 +0200'>2016-07-20</span></td><td><a href='/guix/commit/m4/guix.m4?id=7575655212ecfbcd1f04e429c8a7a41f8720d027'>Merge branch 'master' into core-updates</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2016-07-19 00:07:12 +0200'>2016-07-19</span></td><td><a href='/guix/commit/m4/guix.m4?id=721539026dda02e58addbb618f2102b31a2927f8'>Add (guix zlib).</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2016-06-23 17:25:37 +0300'>2016-06-23</span></td><td><a href='/guix/commit/m4/guix.m4?id=875715cabfeb7816cea16269cfbdbad08442a73e'>build: Remove unneeded conditionals for (guix build syscalls).</a><span class='msg-avail'>...</span></td><td>Manolis Ragkousis</td></tr>
<tr><td><span title='2016-03-19 15:07:46 +0100'>2016-03-19</span></td><td><a href='/guix/commit/m4/guix.m4?id=ef5f5c8659b1ca3999e362dfa33478e0a0150ced'>build: Protect against misconfiguration of localstatedir.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2016-01-13 11:13:34 +0100'>2016-01-13</span></td><td><a href='/guix/commit/m4/guix.m4?id=93ce8a8e0060dedbe97581c1a6e365336d5b4969'>build: Use 127 as the Linux hash-bang limit.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2016-01-12 17:47:36 +0100'>2016-01-12</span></td><td><a href='/guix/commit/m4/guix.m4?id=bb251307642242bb9174e9c4d89909ca40926d67'>build: 'make check' errors out if file name limits would be hit.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2016-01-12 17:47:36 +0100'>2016-01-12</span></td><td><a href='/guix/commit/m4/guix.m4?id=27ab3cee754d89135083b778a00675d9a2d00415'>build: Warn against long hash bang lines for tests.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2015-12-01 00:02:54 +0200'>2015-12-01</span></td><td><a href='/guix/commit/m4/guix.m4?id=dfdb15d9c2badaebfd6a047b303b687ff251256a'>build: Fix detection of ARM systems.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2015-11-25 17:01:02 +0100'>2015-11-25</span></td><td><a href='/guix/commit/m4/guix.m4?id=968ae903189c6c4a41c0e2cddf41ffc5a8c32f93'>build: Reject ARMv6 systems.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>