From: Lars Ingebrigtsen <larsi@gnus.org>
To: Paul Eggert <eggert@cs.ucla.edu>
Cc: 8215@debbugs.gnu.org, Kenichi Handa <handa@m17n.org>
Subject: bug#8215: possibly uninitialized variable lower_xoff in produce_glyphless_glyph
Date: Wed, 02 Jun 2021 10:06:29 +0200 [thread overview]
Message-ID: <87k0ncelmi.fsf@gnus.org> (raw)
In-Reply-To: <4D77F86C.9080809@cs.ucla.edu> (Paul Eggert's message of "Wed, 09 Mar 2011 14:00:12 -0800")
Paul Eggert <eggert@cs.ucla.edu> writes:
> In the meantime, I plan to work around the problem by initializing
> lower_xoff to 0, with a FIXME explaining the situation: this shouldn't
> introduce a bug, because at worst it will replace undefined behavior
> with defined behavior.
It looks like this code is still in place now, ten years later:
diff --git a/src/xdisp.c b/src/xdisp.c
index 44cb713011..44a317b578 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -22292,7 +22292,13 @@ produce_glyphless_glyph (struct it *it, int for_no_font, Lisp_Object acronym)
if (metrics_upper.width >= metrics_lower.width)
lower_xoff = (width - metrics_lower.width) / 2;
else
- upper_xoff = (width - metrics_upper.width) / 2;
+ {
+ /* FIXME: This code doesn't look right. It formerly was
+ missing the "lower_xoff = 0;", which couldn't have
+ been right since it left lower_xoff uninitialized. */
+ lower_xoff = 0;
+ upper_xoff = (width - metrics_upper.width) / 2;
+ }
}
/* +5 is for horizontal bars of a box plus 1-pixel spaces at
Anybody have any insight into whether this is correct or not now?
--
(domestic pets only, the antidote for overdose, milk.)
bloggy blog: http://lars.ingebrigtsen.no
next prev parent reply other threads:[~2021-06-02 8:06 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-09 22:00 bug#8215: possibly uninitialized variable lower_xoff in produce_glyphless_glyph Paul Eggert
2021-06-02 8:06 ` Lars Ingebrigtsen [this message]
2021-06-02 13:17 ` Eli Zaretskii
2021-06-06 9:00 ` Lars Ingebrigtsen
2021-06-06 9:13 ` Eli Zaretskii
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