REGRESSION (r20042): Console spews "CGContextGetType: invalid context" non-stop on web site

[David Kilzer (:ddkilzer)]

Summary:

The following message spews non-stop to the console when the URL (http://tf1.lci.fr/) is loaded:

CGContextGetType: invalid context

This is a fairly recent regression (within the last 24 hours).

Steps to reproduce:

1. Open WebKit debug build.
2. Access URL:  http://tf1.lci.fr/
3. Wait for page to load.

Expected results:

No "CGContextGetType: invalid context" messages should be printed to the console.

Actual results:

The "CGContextGetType: invalid context" messages are printed to the console non-stop until the page is closed.

Regression:

This wasn't happening with debug builds less than 24 hours ago.

[David Kilzer (:ddkilzer)]

Note that the URL is from Bug 12980.

[Stephanie Lewis]

<rdar://problem/5048788>

[David Kilzer (:ddkilzer)]

Of course, I can't reproduce it now.  Probably a particular ad was being displayed.

If anyone sees this again, please save a webarchive of the page.

[David Kilzer (:ddkilzer)]

(In reply to comment #3)
> Of course, I can't reproduce it now.  Probably a particular ad was being
> displayed.

I was missing a step in the steps to reproduce:

1. Open WebKit debug build.
2. Access URL:  http://tf1.lci.fr/
3. Wait for page to load.
4. Hide Safari.

As soon as Safari is hidden, the message starts spewing to the console and never stops until the browser window is closed.

[David Kilzer (:ddkilzer)]

This is a regression from r20042 which was the fix for Bug 12515.

[David Kilzer (:ddkilzer)]

I'm also seeing these console messages sporadically (on this URL, for example: http://www.flickr.com/search/?q=cute+kittens&s=int):

Not a JPEG file: starts with 0x7b 0x35
Not a JPEG file: starts with 0x7b 0x35
Not a JPEG file: starts with 0x7b 0xbd
Not a JPEG file: starts with 0x7b 0x35
Not a JPEG file: starts with 0x7b 0xcb
Not a JPEG file: starts with 0x7b 0x35
Not a JPEG file: starts with 0x7b 0x35
Not a JPEG file: starts with 0x7b 0x35
Not a JPEG file: starts with 0x7b 0x35

I'm not sure if this is caused by r20042 or not, though.

[David Kilzer (:ddkilzer)]

(In reply to comment #6)
> I'm also seeing these console messages sporadically (on this URL, for example:
> http://www.flickr.com/search/?q=cute+kittens&s=int):
> 
> Not a JPEG file: starts with 0x7b 0x35
> [...]
> 
> I'm not sure if this is caused by r20042 or not, though.

This appears to have been a different issue.  Please ignore it.

[David Kilzer (:ddkilzer)]

(In reply to comment #7)
> This appears to have been a different issue.  Please ignore it.

And is fixed as of r20057.

[Matt Lilek]

(In reply to comment #4)
> 
> As soon as Safari is hidden, the message starts spewing to the console and
> never stops until the browser window is closed.
> 

The website http://weplayanything.com spews this before anything is even rendered, without having to hide Safari.

[Bruce Q. Hammond]

Created attachment 13549 [details]
Checks for null ptr before calling WKCGContextIsBitmapContext.

A fairly trivial (low-risk) fix for this issue

[Darin Adler]

Comment on attachment 13549 [details]
Checks for null ptr before calling WKCGContextIsBitmapContext.

r=me

Do you know why there's a null context?

[Mark Rowe (bdash)]

Landed in r20077.