Re: [Patch] reduced warnings reported by clang

[Rich Felker <dalias@libc.org>]

On Tue, Jan 09, 2018 at 06:01:49PM +0100, Markus Wichmann wrote:
> On Tue, Jan 09, 2018 at 04:48:02PM +0000, Patrick Cheng wrote:
> > Hello,
> > 
> > Not sure if it's the version of clang that I was using, or the warning
> > level/toggle on the project that I was compiling, but Musl headers were
> > causing a number of warnings.
> > 
> > Added extra parenthesis, so it's more explicit the precedence of | vs &
> > 
> > Added 'const' to the typecasting. Clang didn't like const casting.
> > 
> 
> Didn't we have this topic already? If clang reports warnings from system
> headers, it is broken. Either because it is not told those headers are
> from the system (did you use -I instead of -isystem?) or because clang
> is broken fundamentally. The latter appears to be unlikely, but I've
> seen horses puke before.

Yes, musl policy is not to let compiler warning whims dictate the way
code or headers are written, on the assumption that musl itself is
built with the warning options it's intended to be used with, and that
compilers do not generate warnings for system headers.

As you noted, usually when this topic comes up it means the user has
not installed musl correctly and is trying to manually -I it rather
than using a musl-targeting toolchain or the provided wrapper scripts.
So it tends to be a helpful warning that something else is wrong in
the user's setup.

Rich