[cfe-commits] [PATCH] Remove -Wdisabled-macro-expansion

[Chandler Carruth]

On Mon, Oct 29, 2012 at 5:53 PM, Eli Friedman <eli.friedman at gmail.com> wrote:
> Per subject, remove -Wdisabled-macro-expansion.  It's triggering on
> normal uses of stdbool.h in C++ (at least, however normal it is to use
> stdbool.h in C++). Because we're trying to encourage people to use
> -Weverything

I don't care at all about this warning, but this statement confused me.

When Ted originally checked in -Weverything it was with the express
intent of *not* being for general use, but being primarily for Clang
developers or folks exploring the total set of warnings available.

There is a *long* path toward changing that state of the world
including contradictory warnings and duplicate warnings which are
often needed to be compatible with other compilers, different code
bases' expectations of different compilers, and a long legacy of
warning (mis)use. Essentially, I don't think we're in a good position
to use "-Weverything isn't user-friendly" as a justification for
changing warnings. That said, there may well be very good reasons to
get rid of this warning. For example...

> it isn't acceptable for it to trigger warnings for usage
> of headers included with the compiler,

It does seem deeply questionable to have a warning that makes a
fundamental feature of the compiler hard (or impossible) to use
without triggering the warning.

That said, -Wgnu? ;] We've actually got precedent for just such a thing...