Re: GDB and compiler-operations

[Paul Eggert]

On 09/07/2018 08:58 AM, Stefan Monnier wrote:
> > On a newer platform where GDB can see C macros (you really should enable
> > this if you can, by the way, it mak,es debugging easier),
> I'm on Debian testing, which doesn't strike me as old.
> How new does it need to be?

Sorry, don't know offhand. But tool age doesn't appear to apply to you 
(see below).

> > I see this:
> >
> > (gdb) p offsetof (struct Lisp_Vector, contents)
> > No symbol "__builtin_offsetof" in current context.
> Hmm... indeed that's the error I was seeing the other day, but today
> I get the other one.  IIRC this was the same machine, tho (and if not,
> it was one running Debian testing or Debian stable, so nothing newer).


Most likely when you were getting the other message you compiled with 
plain -g instead of -g3. './configure' tries to default to -g3 if 
available but perhaps you overrode that, or it didn't work for you.