81965 - Floater layout errors (frame already assoc w/ region)

Status: RESOLVED WORKSFORME

(Core :: Layout, defect)

Description

[Randell Jesup [:jesup] (needinfo me)]

FreeBSD 4.1 Mozilla 20010515xx(?) (not sure exact date I last updated)

With the URL above, I get slews of assertions like this:

WARNING: aFrame is already associated with a region, file nsSpaceManager.cpp,
line 718
###!!! ASSERTION: bad floater placement: 'NS_SUCCEEDED(rv)', file
nsBlockReflowState.cpp, line 1019
###!!! Break: at file nsBlockReflowState.cpp, line 1019

I'm attaching a GDB backtrace.  Note this was originally reported in a comment
to bug 54542.

Comment 1

[Randell Jesup [:jesup] (needinfo me)]

Attachment: gdb backtrace and structure dumps

Comment 2

[Christian Mattar]

From bug 54542:

There are about 20 occurences of a <KLR> element, which are never closed, and it 
seems Mozilla chokes on that. If you remove those tags, the page loads in 
reasonable time.

Comment 3

[Chris Waterson]

Is this bug about the warnings? Or the performance? Or both?

Could requests for QA help:

1. If we're assuming that the performance and the floater warnings are
   related, could somebody verify by unfloating the elements and seeing
   if performance is still abysmal?

2. Could somebody create a minimal test case that triggers the warnings?

Thanks!

Comment 4

[Christian Mattar]

What exactly is a floater?
I'd guess anything which is out of normal flow, e.g. CSS-positioned and 
CSS-float elements.
But the page only consists of some tables, images, forms and HRs.

Comment 5

[Randell Jesup [:jesup] (needinfo me)]

I filed the bug about the assertions; I can't tell if there's a separate
performance bug until I get rid of them (it seems like there might be, but who
knows, given the number of assertions?)

Adding perf because it may be a performance issue to get it on the radar.

Comment 6

[Chris Waterson]

For a precise definition of what a floater is, see

  http://www.w3.org/TR/REC-CSS2/visuren.html#floats

Basically, it's anything (except an absolutely positioned element) that's
removed from the normal flow; e.g., using the |align| attribute (<img
align="right">).

Comment 7

[Bill Mason]

Went to examine this page to try to devise a test case and found that the page
is now a 404.

Comment 8

[Kevin Berkheiser]

This is marked qawanted but the URL is bad and there are not testcases.  What is
the proper procedure?

Comment 9

[Daniel Wang]

I doubt the assignee (Chris Waterson) keeps a copy of the source code,
so... no testcase/url, no bug :-p -> worksforme