729851 - "ASSERTION: Precomputed tab widths are missing!" with DRAWWINDOW_DO_NOT_FLUSH

Status: NEW

(Core :: Layout: Text and Fonts, defect)

Description

[Jesse Ruderman]

Attachment: testcase that relies on thumbnail service & timing

1. Load the testcase.
2. Get ready to click the button.
3. Reload the page, then immediately click the button.
4. Wait 2 seconds.

###!!! ASSERTION: Precomputed tab widths are missing!: 'mTabWidths && mTabWidths->mLimit >= i', file layout/generic/nsTextFrameThebes.cpp, line 2949

This testcase relies on the thumbnail service (added in bug 497543) calling drawWindow with DRAWWINDOW_DO_NOT_FLUSH.  The assertion can also be triggered by other chrome-privileged code making the same drawWindow call.

Comment 1

[Jesse Ruderman]

Attachment: testcase that relies on domFuzzLite improvements

This makes it clear that DRAWWINDOW_DO_NOT_FLUSH is required in order to trigger the bug.

Comment 2

[Jesse Ruderman]

Attachment: gdb output for first testcase

Comment 3

[Jesse Ruderman]

Still happens on trunk:

###!!! ASSERTION: Precomputed tab widths are missing!: 'mTabWidths && mTabWidths->mLimit + startOffset >= i', file layout/generic/nsTextFrameThebes.cpp, line 3029

Mats tweaked the assertion in http://hg.mozilla.org/mozilla-central/rev/678cac97bf1a

Comment 4

[Mats Palmgren (inactive)]

Works for me, m-c 5bd6e09f074e ASAN debug build on Linux64.