WITH_CTF vs -g

[John-Mark Gurney]

Pedro Giffuni wrote this message on Wed, Sep 10, 2014 at 13:45 -0500:
> Hi Andriy;
> 
> Il giorno 10/set/2014, alle ore 12:23, Andriy Gapon <avg at FreeBSD.org> ha scritto:
> 
> > 
> > In my opinion WITH_CTF should imply -g in CFLAGS otherwise, as far as I can see,
> > there is nothing to generate CTF data from.  Forcing an end-user to remember to
> > additionally pass -g is not nice.
> > 
> 
> My understanding is that CTF is meant to be a debugging format independent of DWARF,
> so it should be especially useful for the cases where there is no debugging information.

Except that the CTF data is generated from the DWARF data...  Hence
why you need to compile w/ -g...  ctfconvert uses the DWARF data to
make the CTF data...

> Just like Illumos, we haven?t really made much (or any) use of CTF outside the kernel
> but now that is an option:
> 
> http://dtrace.org/blogs/rm/2013/11/14/userland-ctf-in-dtrace/ 
> 
> 
> > Also, I think that we can always have -g in CTFFLAGS, because the stripping step
> > takes care of the original DWARF data in any case.  But I am not 100% sure about
> > this.
> > 
> 
> > What do you think?
> 
> 
> BTW, it would be nice to see what we can take from the CTF/DDB GSoC [1]. I understand
> the BSD-licensed CTF library has advanced greatly but still needs more work.

Yeh, I need to look at this more too as there are somethings I would
like to do w/ CTF that I can't because the library we have doesn't
export all the data..

-- 
  John-Mark Gurney				Voice: +1 415 225 5579

     "All that I will do, has been done, All that I have, has not."