[webkit-dev] WebKit debugging on OSX and ~/.lldbinit

[Simon Fraser]

On Feb 24, 2015, at 3:10 PM, Sylvain Galineau <galineau at adobe.com> wrote:

> I’ve recently found myself in the following situation while debugging 
> WebKit: the debugger (Xcode) would hit a breakpoint, I would place a new 
> breakpoint in a method up the current call stack, re-run my test and 
> then…nothing. The new breakpoint would never be hit though the original 
> one still was and I could still see that method on the call stack with my 
> breakpoint in it.
> 
> For instance, I would set a breakpoint in FontCascade::width(), see 
> RenderSVGText::layout() on the call stack then set a breakpoint in the 
> latter. I’d try my test again and never break into 
> RenderSVGText::layout(). 
> 
> I verified I was using a debug build, rebuilt from scratch, tried 
> command-line LLDB, stood on my head, no luck.
> 
> Until I added:
> 
> 	settings set target.inline-breakpoint-strategy always
> 
> 
> in ~/.lldbinit.
> 
> I’m glad it works - yay breakpoints - but am not quite sure why this bit 
> of magic is needed. Does anyone else use this/know why it helps?  

This is a known issue (tracked internally as rdar://problem/16829492). It’s
exacerbated by our “all in one” .cpp files (e.g. RenderSVGAllInOne.cpp) which
are required to get around linking size issues iirc.

Simon