Copied from Fedora.

https://bugzilla.redhat.com/show_bug.cgi?id=1232265
http://pkgs.fedoraproject.org/cgit/libunwind.git/tree/libunwind-1.1-fix-CVE-2015-3239.patch

diff -up libunwind-1.1/include/dwarf_i.h.CVE20153239 libunwind-1.1/include/dwarf_i.h
--- libunwind-1.1/include/dwarf_i.h.CVE20153239	2015-07-10 13:38:36.404996748 -0400
+++ libunwind-1.1/include/dwarf_i.h	2015-07-10 13:39:25.050707613 -0400
@@ -20,7 +20,7 @@
 extern const uint8_t dwarf_to_unw_regnum_map[DWARF_REGNUM_MAP_LENGTH];
 /* REG is evaluated multiple times; it better be side-effects free!  */
 # define dwarf_to_unw_regnum(reg)					  \
-  (((reg) <= DWARF_REGNUM_MAP_LENGTH) ? dwarf_to_unw_regnum_map[reg] : 0)
+  (((reg) < DWARF_REGNUM_MAP_LENGTH) ? dwarf_to_unw_regnum_map[reg] : 0)
 #endif
 
 #ifdef UNW_LOCAL_ONLY
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<tr><td><span title='2019-01-15 14:46:44 +0100'>2019-01-15</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=44d10b1f722856ab8e9b942804aa7ef33e2ef739'>gnu: Separate Python core packages from the rest.</a><span class='msg-avail'>...</span></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2018-11-11 17:18:05 +0100'>2018-11-11</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=8c5749f1b5255e37a6ef7b43e48fe0bbc57ce209'>gnu: python-cffi: Fix test failure on i686.</a><span class='msg-avail'>...</span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2018-08-22 18:01:10 +0200'>2018-08-22</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=22cf2f4abfa2b1ad5620d35644b6538b7041dbf1'>gnu: python-cffi: Update to 1.11.5.</a><span class='msg-avail'>...</span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2018-08-21 17:24:29 +0200'>2018-08-21</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=1935b8d56a4c739f468af973ac9057463c18d1bc'>gnu: libffi: Don't optimize for the build machine CPU.</a><span class='msg-avail'>...</span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2018-03-29 17:34:41 +0200'>2018-03-29</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=5576cfabf3485e0cf794cc3de085a3578151ee64'>Merge branch 'master' into core-updates</a></td><td>Marius Bakke</td></tr>
<tr><td><span title='2018-03-25 00:36:35 +0100'>2018-03-25</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=a26040c5eeb04826618485ed3de487fa1b5768f7'>gnu: ruby-ffi: Update to 1.9.23.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2018-03-14 17:37:20 +0100'>2018-03-14</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=8c72ed923d77ee55989965bb02628043799b9548'>Merge branch 'master' into core-updates</a></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2018-02-26 20:13:11 +0100'>2018-02-26</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=fc38e317cde56897b575c5af2d7787d889323193'>gnu: python-cffi: Update phase style.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2018-02-26 20:13:11 +0100'>2018-02-26</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=b737530569844d1538a45f209460fedc0edf7497'>gnu: python-cffi: Update to 1.11.4.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2018-02-26 20:13:10 +0100'>2018-02-26</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=9de33cc726cb4d050ea722ec6a8ceb7613d676a2'>gnu: ruby-ffi: Update to 1.9.22.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2018-02-20 16:06:10 +0100'>2018-02-20</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=667e6f1e24b12ba7f37ad518c40cf66c98ce8625'>gnu: libffi: Update phase style.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</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/libffi.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='2017-10-15 11:57:15 +0300'>2017-10-15</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=838b232e974014927d098bf1128aaf49dd785b80'>gnu: ruby-ffi: Move to libffi.scm.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2017-10-15 11:57:15 +0300'>2017-10-15</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=0751fddd919d4cd7017500c155e5b24d4023d621'>gnu: python-cffi: Move to libffi.scm</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2017-04-13 14:44:27 +0200'>2017-04-13</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=dc4ebebd61896b1122fde97644325d06e3f46b47'>gnu: libffi: Fix builds on Alpha.</a><span class='msg-avail'>...</span></td><td>Sergei Trofimovich</td></tr>
<tr><td><span title='2017-04-02 20:00:51 -0400'>2017-04-02</span></td><td><a href='/guix/commit/gnu/packages/libffi.scm?id=7bf837fd43e274eba00dab0644a8df6dfa055d08'>gnu: Use HTTPS URLs for GitHub home-pages.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>