Subject: bug#53058: etc/DEBUG could say more about --enable-check-lisp-object-type

From: Sean Whitton <[email-masked]>
Date: Wed, 02 Feb 2022 17:19:04 -0700

Hello,

On Sat 08 Jan 2022 at 08:55am +02, Eli Zaretskii wrote:

> The reasons for the problem in your case is not known: NILP should
> have worked, as did the comparison with Qnil.  Until we understand why
> those didn't work, I don't see how we can say anything in etc/DEBUG
> that would both be useful and important/general enough to have there.
>
> My best advice is to try to understand why those conditions didn't
> work on your system.  Maybe someone here knowns, or maybe you should
> ask on the GDB mailing list ([email-masked]).

If I understand you correctly: we don't yet know exactly what was going
wrong on my machine when I tried to set the conditional break point, so
we lack a concrete case in which --enable-check-lisp-object-type
affected debugging with GDB, and we are thus not in a position to assert
in etc/DEBUG that --enable-check-lisp-object-type has the potential to
have an effect on debugging with gdb?

When you wrote that comparisons with structs are not guaranteed to work
with gdb, you were /not/ going as far as saying that comparisons with
structs are never expected to work (because that would imply that
--enable-check-lisp-object-type would often lead to issues when
debugging)?

If this summary is right, I think this bug should be closed.

Thanks.

-- 
Sean Whitton