1517767 - Crash in apply_forward

Status: RESOLVED WORKSFORME

(Core :: Graphics: Text, defect, P3)

Description

[Calixte Denizet (:calixte)]

This bug was filed from the Socorro interface and is
report bp-3a2425d8-8a8f-4572-af03-871160190104.
=============================================================

Top 10 frames of crashing thread:

0 xul.dll static bool apply_forward gfx/harfbuzz/src/hb-ot-layout.cc:1338
1 xul.dll static void apply_string<GSUBProxy> gfx/harfbuzz/src/hb-ot-layout.cc:1395
2 xul.dll hb_ot_map_t::apply<GSUBProxy> gfx/harfbuzz/src/hb-ot-layout.cc:1441
3 xul.dll hb_ot_shape gfx/harfbuzz/src/hb-ot-shape.cc:998
4 xul.dll hb_shape_full gfx/harfbuzz/src/hb-shape.cc:139
5 xul.dll gfxHarfBuzzShaper::ShapeText gfx/thebes/gfxHarfBuzzShaper.cpp:1413
6 xul.dll gfxFont::ShapeText gfx/thebes/gfxFont.cpp:2761
7 xul.dll bool gfxFont::ShapeText gfx/thebes/gfxFont.cpp:2733
8 xul.dll gfxFont::GetShapedWord<unsigned char> gfx/thebes/gfxFont.cpp:2673
9 xul.dll gfxFont::SplitAndInitTextRun<unsigned char> gfx/thebes/gfxFont.cpp:3035

=============================================================

There is 1 crash in nightly 66 with buildid 20190103094209. In analyzing the backtrace, the regression may have been introduced by patch [1] to fix bug 1500356.

[1] https://hg.mozilla.org/mozilla-central/rev?node=2d077b8e0b5b

Comment 1

[Jonathan Kew [:jfkthame]]

From crash-stats, it doesn't look like this is a new regression; it's been happening (with very low frequency) for many months, at least, across multiple Firefox (and Thunderbird) versions and multiple platforms.

Comment 2

[Jonathan Kew [:jfkthame]]

I opened https://github.com/mozilla/clouseau/issues/123 as I don't think this report was at all accurate as filed.

Comment 3

[Behdad Esfahbod]

Is there anything that can help me debug this, other than the stacktrace?

Comment 4

[Jonathan Kew [:jfkthame]]

Not AFAIK, unfortunately. We don't have a testcase or any hint as to what font is being used.

It seems to be a longstanding but infrequent issue, mostly just sporadic one-off crashes (on various platforms: windows, mac, android), though occasionally we see several reports from the same user, such as the 3 crash reports from a single Win7 user on 2018-11-29: https://crash-stats.mozilla.com/signature/?build_id=20180903060751&product=Firefox&signature=apply_forward&date=%3E%3D2018-07-08T00%3A23%3A39.000Z&date=%3C2019-01-07T22%3A23%3A39.000Z&_columns=date&_columns=product&_columns=version&_columns=build_id&_columns=platform&_columns=reason&_columns=address&_columns=install_time&_sort=-date&page=1#reports

Comment 5

[BugBot [:suhaib / :marco/ :calixte]]

Since the crash volume is low (less than 5 per week), the severity is downgraded to S3. Feel free to change it back if you think the bug is still critical.

For more information, please visit auto_nag documentation.

Comment 6

[BugBot [:suhaib / :marco/ :calixte]]

Closing because no crashes reported for 12 weeks.