1587369 - Assertion failure: false (Two layers that scroll together have different ancestor transforms), at /home/allstars/src/gecko/gfx/layers/apz/src/APZCTreeManager.cpp:1200

Status: RESOLVED WORKSFORME

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

Description

[Yoshi Cheng-Hao Huang [:allstars.chh][:allstarschh][:yoshi]]

visit https://tamildigitallibrary.in/
then firefox crashes

hg commit: 26ebfec0883457409f3d2ff8bc882b3b6f4936b2

Comment 1

[Kris Taeleman (:ktaeleman)]

Hey Yoshi,

Can you provide attach your about:support file and links to the crash reports in about:crashes?

Comment 2

[Yoshi Cheng-Hao Huang [:allstars.chh][:allstarschh][:yoshi]]

Attachment: gdb.txt

the crash report I got is all with hex numbers, and I don't have the permission to upload the symbols, so I attached the gdb log here. (I think the assertion is from thread 20)

about:support is https://pastebin.com/7LhL8vZr

Comment 3

[Kris Taeleman (:ktaeleman)]

@botond: Can you take a look at this?

Comment 4

[Botond Ballo [:botond]]

This is a debug-only assertion, and one that we have existing reports about (bug 1450686, bug 1491000), though this is the first time we see it in the wild (the existing reports are fuzzer testcases).

Yoshi, were you running a debug build of Firefox when you encountered this?

Comment 5

[Botond Ballo [:botond]]

The issue seems to be specific to WR (like bug 1491000, and unlike bug 1450686).

My suggestions for next steps are:

• Fix bug 1491000 first, since that has a reduced testcase
• Check if that fixes this too
• If not, prepare a reduced testcase based on this website and investigate that

Comment 6

[Yoshi Cheng-Hao Huang [:allstars.chh][:allstarschh][:yoshi]]

(In reply to Botond Ballo [:botond] from comment #4)

Yoshi, were you running a debug build of Firefox when you encountered this?

yes

Comment 7

[Botond Ballo [:botond]]

I suspect this has been fixed (perhaps by bug 1719913, though it could have been something else). Yoshi, could you check please if the assertion failure is still reproducible in the latest Firefox Nightly?

Comment 8

[Yoshi Cheng-Hao Huang [:allstars.chh][:allstarschh][:yoshi]]

working fine now, tried this in DEBUG build but didn't get any assertion.

Comment 9

[Botond Ballo [:botond]]

Thanks for checking!