Re: [PATCH 01/13] btrfs-progs: turn on more compiler warnings and use -Wall

[David Sterba <dsterba@suse.cz>]

On Tue, Mar 08, 2022 at 07:15:03PM +0100, David Sterba wrote:
> On Tue, Mar 08, 2022 at 05:51:26PM +0100, David Sterba wrote:
> > On Tue, Feb 22, 2022 at 05:26:11PM -0500, Josef Bacik wrote:
> > > In converting some of our helpers to take new args I would miss some
> > > locations because we don't stop on any warning, and I would miss the
> > > warning in the scrollback.  Fix this by stopping compiling on any error
> > > and turn on the fancy compiler checks.
> > > 
> > > Signed-off-by: Josef Bacik <josef@toxicpanda.com>
> > > ---
> > >  Makefile | 3 +++
> > >  1 file changed, 3 insertions(+)
> > > 
> > > diff --git a/Makefile b/Makefile
> > > index af4908f9..e0921ca3 100644
> > > --- a/Makefile
> > > +++ b/Makefile
> > > @@ -93,6 +93,9 @@ CFLAGS = $(SUBST_CFLAGS) \
> > >  	 -D_XOPEN_SOURCE=700  \
> > >  	 -fno-strict-aliasing \
> > >  	 -fPIC \
> > > +	 -Wall \
> > > +	 -Wunused-but-set-parameter \
> > > +	 -Werror \
> > 
> > That's in the default flags and based on the recent experience in kernel
> > defaulting to Werror it creates more problems than not. The build is
> > clean enough that new warnings are quite obvious and get fixed right
> > away.
> > 
> > You can always use the EXTRA_CFLAG=-Werror when developing or you can
> > also set CFLAGS=-Werror at configure time, as they get stored in the
> > generated Makefile.inc into SUBST_CFLAGS.
> 
> And actually there's make parameter W=1 like in kernel, that enables
> more warnings though the W=1 build is not clean. I'd rather not clutter
> the default flags by random warnings at all as the build is supposed to
> work on various LTS distros and compilers so that would probably fail
> build.

Ok, so not theoretical, the musl and centos7 builds fail, so I'm
dropping the patch.