Fix CVE-2016-5296: Heap-buffer-overflow WRITE in rasterize_edges_1
Adapted for upstream pixman based on:

  https://hg.mozilla.org/releases/mozilla-esr45/rev/5e39c1c2fded

--- pixman-0.34.0/pixman/pixman-edge-imp.h.orig	2015-06-30 05:48:31.000000000 -0400
+++ pixman-0.34.0/pixman/pixman-edge-imp.h	2016-11-16 01:09:34.046335106 -0500
@@ -55,8 +55,9 @@
 	 *
 	 * (The AA case does a similar  adjustment in RENDER_SAMPLES_X)
 	 */
-	lx += X_FRAC_FIRST(1) - pixman_fixed_e;
-	rx += X_FRAC_FIRST(1) - pixman_fixed_e;
+	/* we cast to unsigned to get defined behaviour for overflow */
+	lx = (unsigned)lx + X_FRAC_FIRST(1) - pixman_fixed_e;
+	rx = (unsigned)rx + X_FRAC_FIRST(1) - pixman_fixed_e;
 #endif
 	/* clip X */
 	if (lx < 0)
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<tr><th>author</th><td>Marius Bakke &lt;mbakke@fastmail.com&gt;</td><td class='right'>2019-03-14 15:06:06 +0100</td></tr>
<tr><th>committer</th><td>Marius Bakke &lt;mbakke@fastmail.com&gt;</td><td class='right'>2019-03-14 15:06:06 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/guix/commit/?id=ebfe259f6682b43d7f0d3b57b525e25f97410052'>ebfe259f6682b43d7f0d3b57b525e25f97410052</a> (<a href='/guix/patch/?id=ebfe259f6682b43d7f0d3b57b525e25f97410052'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/guix/tree/?id=ebfe259f6682b43d7f0d3b57b525e25f97410052'>e3f09eb6159168e1736f8a629286eb3d148917a9</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/guix/commit/?id=47b3eed821cf86c350dc4b0fdbe75647cdc275b0'>47b3eed821cf86c350dc4b0fdbe75647cdc275b0</a> (<a href='/guix/diff/?id=ebfe259f6682b43d7f0d3b57b525e25f97410052&amp;id2=47b3eed821cf86c350dc4b0fdbe75647cdc275b0'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/guix/commit/?id=8cc3983a4d02a15ad4a863671c1a5a8b2b542625'>8cc3983a4d02a15ad4a863671c1a5a8b2b542625</a> (<a href='/guix/diff/?id=ebfe259f6682b43d7f0d3b57b525e25f97410052&amp;id2=8cc3983a4d02a15ad4a863671c1a5a8b2b542625'>diff</a>)</td></tr><tr><th>download</th><td colspan='2' class='oid'><a href='/guix/snapshot/guix-ebfe259f6682b43d7f0d3b57b525e25f97410052.tar.gz'>guix-ebfe259f6682b43d7f0d3b57b525e25f97410052.tar.gz</a><br/><a href='/guix/snapshot/guix-ebfe259f6682b43d7f0d3b57b525e25f97410052.zip'>guix-ebfe259f6682b43d7f0d3b57b525e25f97410052.zip</a><br/></td></tr></table>
<div class='commit-subject'>Merge branch 'master' into staging</div><div class='commit-msg'></div><div class='diffstat-header'><a href='/guix/diff/?id=ebfe259f6682b43d7f0d3b57b525e25f97410052'>Diffstat</a></div><table summary='diffstat' class='diffstat'>