[webkit-dev] showTree crashes in gdb

[Benjamin Kalman]

Hi

I've noticed ever since working with DOM and editing code that showTree
often doesn't work.  As in, it segfaults from gdb (or prints Chinese
characters rather than a DOM).  It seems to be especially bad recently;
though this might just reflect my gradually diminishing patience.

I had a brief look myself and came away with observations:

   - It only happens from gdb's command line.  Compiling in a call to
   showTree(foo) works, while breaking on that line and running "call
   showTree(foo)" from gdb crashes.
   - The segfault trace is different every time, but is usually in RefPtr
   code.
   - Sometimes "call showTree(foo)" will work, but calling it again will
   crash.
   - Stepping through showTree in gdb, IIRC the segfault happens right after
   stepping out of one of the methods.  I can't remember which one, nor whether
   it was predictably the same method.

Hesitant conclusion: there is a bug in gdb tickled by something in RefPtr,
perhaps the funky operator overriding behaviour, but my C++ isn't good
enough to fully understand why this might happen.

Has anybody else looked into this before?  It would be really really
convenient to be able to rely on showTree.

-- Ben
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.webkit.org/pipermail/webkit-dev/attachments/20110321/49a2f86e/attachment.html>