Re: More C type errors by default for GCC 14

[Eli Zaretskii <eliz@gnu.org>]

> From: Jonathan Wakely <jwakely.gcc@gmail.com>
> Date: Wed, 10 May 2023 12:49:52 +0100
> Cc: David Brown <david@westcontrol.com>, gcc@gcc.gnu.org
> 
> > If some developers want to ignore warnings, it is not the business of
> > GCC to improve them, even if you are right in assuming that they will
> > not work around errors like they work around warnings (and I'm not at
> > all sure you are right in that assumption).  But by _forcing_ these
> > errors on _everyone_, GCC will in effect punish those developers who
> > have good reasons for not changing the code.
> 
> There will be options you can use to continue compiling the code
> without changing it. You haven't given a good reason why it's OK for
> one group of developers to have to use options to get their desired
> behaviour from GCC, but completely unacceptable for a different group
> to have to use options to get their desired behaviour.
> 
> This is just a change in defaults.

A change in defaults that is not backward-compatible should only be
done for very good reasons, because it breaks something that was
working for years.  No such good reasons were provided.  And no,
educating/forcing GCC users to use more modern dialect of C is not a
good reason.

> Accepting broken code by default is not a priori a good thing, as
> you seem to insist. Rejecting it by default is not a priori a good
> thing. There is a pragmatic choice to be made, and your argument is
> still no more than "it compiles today, so it should compile
> tomorrow".

Once again: it isn't "broken code".  It is dangerous code, and in some
cases unintentionally suspicious code.  But it isn't broken, because
GCC can compile it into a valid program, which, if the programmer
indeed meant that, will work and do its job.

> > > Agreed.  But if we can make it harder for them to release bad code,
> > > that's good overall.
> >
> > I'm okay with making it harder, but without making it too hard for
> > those whose reasons for not changing the code are perfectly valid.
> > This proposal crosses that line, IMNSHO.
> 
> Where "too hard" means using a compiler option. Seriously? This seems farcical.

This goes both ways, of course.  GCC had -Werror since about forever.