[cfe-dev] How to debug a clang compiled executable.

[Sean McBride]

On Wed, 28 Jul 2010 17:04:47 -0700, Bill Wendling said:

>> strncat_chk is used because you defined _FORTIFY_SOURCE.  IIRC, it helps
>> check for overruns using C string functions.  I believe in 10.5 the
>> _FORTIFY_SOURCE version of strncat was screwy, ah, here you go:
>> 
>> <http://lists.apple.com/archives/xcode-users/2008/Jul/msg00848.html>
>> 
>> I think it's fixed on 10.6.
>> 
>> Try again without -D_FORTIFY_SOURCE=2, and maybe remove -fstack-
>> protector-all too.
>> 
>Ewww...don't remove the "-fstack-protector-all". It's your friend. :) If

It is one's friend, in general.

>it's aborting because of the stack protector, then you have a definite
>buffer overrun.

That's fallacious.  It could be aborting because of a bug with -fstack-
protector-all, which is exactly what I'm saying.  See <rdar://6105964>
if you have access.

-- 
____________________________________________________________
Sean McBride, B. Eng                 sean at rogue-research.com
Rogue Research                        www.rogue-research.com 
Mac Software Developer              Montréal, Québec, Canada