Re: rules, rules, and more (code policy) rules

[Simon Josefsson]

I'm going through Coreutils GNUmakefile and Makefile.maint to identify
useful rules.  Some question pop up:

1)

Is this rule generally safe?  Does it assume GNU tar?  Is there a real
problem solved by this, or is it just "nice"?

# Make tar archive easier to reproduce.
export TAR_OPTIONS = --owner=0 --group=0 --numeric-owner

Further, shouldn't automake set this, if it is safe?

2)

The following is not safe, --rsyncable is a new feature.

# Do not save the original name or timestamp in the .tar.gz file.
GZIP_ENV = '--no-name --best --rsyncable'

Perhaps this, and the previous case, should be moved to a m4 macro, to
find out whether the parameters are supported or not.  Thoughts?

Thanks,
Simon