Re: Using $program_transform_name from ‘configure’

[Eric Blake]

On 04/24/2014 03:54 AM, Ludovic Courtès wrote:

>> I don't see an AC_CONFIG_FILES() in configure.ac that tries to create
>> guild solely at configure time.  Therefore, I assume it's being created
>> at make time - but which Makefile.am is responsible for creating it?
> 
> No, there was a ‘GUILE_CONFIG_SCRIPT’ invocation in configure.ac, which
> wraps ‘AC_CONFIG_FILES’.
> 
>> _That_ rule would be the place to run $program_transform_name as part of
>> the creation process, rather than trying to shoehorn the conversion into
>> configure.ac.
> 
> Yeah I realized we can easily do that in Makefile.am (and we already did
> for another script), so I took that route:
> 
>   
> http://git.savannah.gnu.org/cgit/guile.git/commit/?id=d80b6acf198dddc90eba40a83de36b65ddf9f0ac

Yay, glad we found a solution.

Useless use of cat:

> + cat $(srcdir)/guild.in \
> + | $(SED) -e "s,@installed_guile@,$$guile,g" \

could be simplified to pass the input file directly as sed's stdin,
rather than through a pipe, as in:

$(SED) < $(srcdir)/guild.in -e ...

Also, two potential gotchas:

You may want to use s,address@hidden@],$$guile,g to match the style
used in the lines below (in fact, doing this is necessary to avoid false
positives if you use gnulib's syntax-check rule that checks for
unsubstituted @var@ in makefiles, where automake $(var) should have been
used instead - but in that case, you'd also want to use $(bindir)
instead of @bindir@ when determining $$guile).

Your use of s,,,g is risky.  If $$guile contains any commas after the
user's program transform, or if @bindir@ contains any commas, you have
an invalid sed script.  You could work around it by changing , to \,
with another sed invocation, if you are worried about this case.

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org

signature.asc
Description: OpenPGP digital signature