Re: [PATCH] gdb, configure: Add disable-formats option for configure

[Andrew Burgess <aburgess@redhat.com>]

Eli Zaretskii <eliz@gnu.org> writes:

>> Date: Tue, 8 Oct 2024 10:03:58 -0300
>> Cc: aburgess@redhat.com, gdb-patches@sourceware.org
>> From: Guinevere Larsen <guinevere@redhat.com>
>> 
>> Ultimately, this is a feature for advanced users who have deep domain 
>> knowledge on the systems they expect to handle, and similar to how, even 
>> with the update on the --target and --enable-targets documentation, I 
>> wouldn't expect every single target triplet supported by GDB to be 
>> listed in the documentation, I don't think we should list what formats 
>> are recommended for each target.
>> 
>> I can change the first paragraph of the description to read as follows:
>>    Configure GDB to only be be able to read selected file formats. The
>>    special value "all" causes all file formats to be compiled in, and is 
>> the
>>    the default behavior of the option. If you are unsure of which options
>>    you will need for your debugging sessions, we recommend that you
>>    not make use of this function. The possible options are:
>> 
>> <list of options as sent in previous email>
>
> Maybe this is better.
>
> I'm worried by the fact that I'm the only one talking to you about
> this: maybe there's no problem at all, and I'm the only one confused.
> In that case, apologies for wasting your time.

I think it's OK to be unsure about this.  You asked a couple of times,
what values would I need to pass to support all the required formats on
target X?  And I don't think you really got a clear answer.

I'll take a stab at answering it: we don't know, and that's OK.

As Gwen said, this option is intended for power users who have a clear
idea about their targets, what file formats are required, and which
formats they want to support.

If a user does NOT have that knowledge then they shouldn't touch this
setting.

The question then becomes, whose job is it to teach the user about their
target, and which file formats it uses.  I agree with Gwen here, that's
not our job.

We should carefully document the possible values that can be passed to
this configure flag.  We should also make it clear what the consequences
of misusing this flag are (i.e. you'll end up with a GDB that can't read
some file formats), and, I think, we should suggest that if a user is in
any doubt then they should leave this flag as its default.  My hope is
that by strengthening the documentation to make this final concrete
recommendation then we hopefully address your concern about a user who
is reading the docs trying to figure out how to build GDB.

On a different note: I haven't forgotten my offer of updating the
--target and --enable-targets docs, it'll probably be next week before I
can work on this though.

Thanks,
Andrew