Copied from Debian.

From: Jérémy Bobbio <lunar@debian.org>
Subject: Remove build date
Bug-Debian: http://bugs.debian.org/782851
 In order to make unzip build reproducibly, we remove the
 (already optional) build date from the binary.

--- a/unix/unix.c
+++ b/unix/unix.c
@@ -1705,7 +1705,7 @@
 #endif /* Sun */
 #endif /* SGI */
 
-#ifdef __DATE__
+#if 0
       " on ", __DATE__
 #else
       "", ""
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<div class='path'>path: <a href='/guix/log/?id=2dfb16150e11f273fd6f991bb563bf02a8a69402'>root</a>/<a href='/guix/log/gnu?id=2dfb16150e11f273fd6f991bb563bf02a8a69402'>gnu</a>/<a href='/guix/log/gnu/packages?id=2dfb16150e11f273fd6f991bb563bf02a8a69402'>packages</a>/<a href='/guix/log/gnu/packages/gps.scm?id=2dfb16150e11f273fd6f991bb563bf02a8a69402'>gps.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/packages/gps.scm?id=2dfb16150e11f273fd6f991bb563bf02a8a69402&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-11-30 00:25:52 +0100'>2020-11-30</span></td><td><a href='/guix/commit/gnu/packages/gps.scm?id=958f6b5aa6c7bad87105384c0fb3920c01590a5f'>gnu: gpxsee: Update to 7.37.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/gps.scm (gpxsee): Update to 7.37.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-11-29 00:02:04 +0200'>2020-11-29</span></td><td><a href='/guix/commit/gnu/packages/gps.scm?id=e07f05667d1fd6e0e1c6971466ce2c56c6031629'>gnu: gama: Update to 2.12.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/gps.scm (gama): Update to 2.12.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2020-11-13 01:27:23 +0100'>2020-11-13</span></td><td><a href='/guix/commit/gnu/packages/gps.scm?id=f41c9ab4c3c65e0588b83eefbd2511716aa6d465'>gnu: gpxsee: Update to 7.36.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/gps.scm (gpxsee): Update to 7.36.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-11-05 03:46:09 +0100'>2020-11-05</span></td><td><a href='/guix/commit/gnu/packages/gps.scm?id=2b03b5f5da008918876b7ec5c5c112bba7d8fea0'>gnu: gpxsee: Update to 7.35.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/gps.scm (gpxsee): Update to 7.35.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-10-28 08:58:06 +0200'>2020-10-28</span></td><td><a href='/guix/commit/gnu/packages/gps.scm?id=0dc301838f4ae3be172a595c1f92279a2d40c714'>gnu: gama: Remove bundled library.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/gps.scm (gama)[source]: Add snippet to remove bundled
expat-1.1 library.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2020-10-28 08:56:50 +0200'>2020-10-28</span></td><td><a href='/guix/commit/gnu/packages/gps.scm?id=0b96047e58c71eef38145702b93dfe6f64a74a80'>gnu: gama: Update to 2.11.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/gps.scm (gama): Update to 2.11.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2020-10-16 17:16:00 +0200'>2020-10-16</span></td><td><a href='/guix/commit/gnu/packages/gps.scm?id=eec4def4f6a4e6e67db96c8acfc5327d2c6d64d6'>gnu: gpxsee: Update to 7.34.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/gps.scm (gpxsee): Update to 7.34.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-09-27 08:50:26 +0300'>2020-09-27</span></td><td><a href='/guix/commit/gnu/packages/gps.scm?id=59223c5bc6816962b95d51fb2e8b7edd91c7fa95'>gnu: gama: Update to 2.10.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/gps.scm (gama): Update to 2.10.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2020-08-16 23:36:27 +0200'>2020-08-16</span></td><td><a href='/guix/commit/gnu/packages/gps.scm?id=6a513960c4784f12b0a1ae818cae00ddef4910b1'>gnu: gpsd: Update to 3.21.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/gps.scm (gpsd): Update to 3.21.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-07-24 15:02:01 +0200'>2020-07-24</span></td><td><a href='/guix/commit/gnu/packages/gps.scm?id=dc6cd35e6d369f7591217065959234e5a23b008e'>gnu: gpscorrelate: Update to 2.0.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/gps.scm (gpscorrelate): Update to 2.0.
[arguments]: Remove #:tests?.
[inputs]: Remove GTK+-2.  Add GTK+.
</span></span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2020-07-01 19:40:24 +0300'>2020-07-01</span></td><td><a href='/guix/commit/gnu/packages/gps.scm?id=ade0f8ea0cbcabcd94cb4212abebd8c143c7d69d'>gnu: gama: Update to 2.09.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/gps.scm (gama): Update to 2.09.
</span></span></td><td>Efraim Flashner</td></tr>