Fix doc snarfing with GCC 4.5+.
From <http://git.savannah.gnu.org/cgit/guile.git/commit/?h=branch_release-1-8&id=aac41d28358cea594bb30f6e547afb82bb6004a6>.

diff --git a/scripts/snarf-check-and-output-texi b/scripts/snarf-check-and-output-texi
index ea33e17..8cd42e8 100755
--- a/scripts/snarf-check-and-output-texi
+++ b/scripts/snarf-check-and-output-texi
@@ -267,6 +267,17 @@ exec ${GUILE-guile} -l $0 -c "(apply $main (cdr (command-line)))" "$@"
       (set! *file* file)
       (set! *line* line))
 
+     ;; newer gccs like to throw around more location markers into the
+     ;; preprocessed source; these (hash . hash) bits are what they translate to
+     ;; in snarfy terms.
+     (('location ('string . file) ('int . line) ('hash . 'hash))
+      (set! *file* file)
+      (set! *line* line))
+
+     (('location ('hash . 'hash) ('string . file) ('int . line) ('hash . 'hash))
+      (set! *file* file)
+      (set! *line* line))
+
      (('arglist rest ...)
       (set! *args* (do-arglist rest)))
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<tr><td><span title='2017-08-29 20:13:24 -0400'>2017-08-29</span></td><td><a href='/guix/commit/gnu/packages/hexedit.scm?id=3c8ba11a97d3f3b671b8919da8c41f0b0e2ccaf3'>Update e-mail for Kei Kebreau.</a><span class='msg-avail'>...<span class='msg-tooltip'>* .mailmap: Map kei@openmailbox.org to current address.
* gnu/local.mk: Replace kei@openmailbox.org to current address.
* gnu/packages/backup.scm: Likewise.
* gnu/packages/calendar.scm: Likewise.
* gnu/packages/check.scm: Likewise.
* gnu/packages/compression.scm: Likewise.
* gnu/packages/documentation.scm: Likewise.
* gnu/packages/emacs.scm: Likewise.
* gnu/packages/fltk.scm: Likewise.
* gnu/packages/freedesktop.scm: Likewise.
* gnu/packages/game-development.scm: Likewise.
* gnu/packages/games.scm: Likewise.
* gnu/packages/gnome.scm: Likewise.
* gnu/packages/gnustep.scm: Likewise.
* gnu/packages/gtk.scm: Likewise.
* gnu/packages/hexedit.scm: Likewise.
* gnu/packages/image.scm: Likewise.
* gnu/packages/maths.scm: Likewise.
* gnu/packages/music.scm: Likewise.
* gnu/packages/xfce.scm: Likewise.
* gnu/packages/python.scm: Likewise.
* gnu/packages/tcl.scm: Likewise.
* gnu/packages/textutils.scm: Likewise.
* gnu/packages/video.scm: Likewise.
* gnu/packages/w3m.scm: Likewise.
* gnu/packages/web.scm: Likewise.
* gnu/packages/web-browsers.scm: Likewise.
* gnu/packages/patches/wmfire-update-for-new-gdk-versions.patch: Likewise.
</span></span></td><td>Kei Kebreau</td></tr>
<tr><td><span title='2017-06-26 16:35:55 +0200'>2017-06-26</span></td><td><a href='/guix/commit/gnu/packages/hexedit.scm?id=24b91ebd2e78a103aee128e5e089b6d6bf339fd9'>gnu: Add ht.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/hexedit.scm (ht): New variable.

Signed-off-by: Tobias Geerinckx-Rice &lt;me@tobias.gr&gt;
</span></span></td><td>Gábor Boskovits</td></tr>