ExtUtils::CBuilder: Apple have started to apply -Werror by default, breaking XS

I recently had trouble building Digest::SHA256:

  http://paste.scsys.co.uk/592749

and a few other XS modules. This only happens on my machines that are running Mac OS Catalina with the latest version of XCode. Older machines can build it Just Fine. It appears that some time recently Apple in their wisdom decided that -Werror should be turned on by default.

The correct fix, of course, is for lazy programmers to fix their damned modules, but that ain't gonna happen. Plenty of them are stable and not actively maintained.

I have raised a ticket (with a patch for at least a partial fix) against ExtUtils::MakeMaker:

  https://rt.cpan.org/Ticket/Display.html?id=133493

Some kind of similar fix will also be needed in ExtUtils::CBuilder, which is maintained by p5p, as that is used by Module::Build. I would create a patch myself, but I don't have an example of an XS build failure that uses that so that I can test my patch. I'm sure they exist though.

-- 
David Cantrell | A machine for turning tea into grumpiness

I'm not sure that's the best place to fix that. Configure should give us all the right flags to compile modules, so I think it should be fixed in hints/darwin.sh instead (that way all end-users are fixed in one go)

Leon

ExtUtils::CBuilder is on the CPAN too so putting a fix in there makes it available to people who have already built their perl, including to users of perls that are no longer getting updates.

-- 
David Cantrell

Being the maintainer of EU::CB in CPAN, I agree with Dave. But somehow I missed the patch.

At the moment I am very busy at the $job, but if someone is able to send me the patch for the CPAN version, I am happy to send an updated version to CPAN.

Thank you
ambs

I found something that fails using EU::CBuilder, so I'll send a patch shortly.

-- 
David Cantrell | semi-evolved ape-thing

https://github.com/Perl/perl5/pull/18234

NB that Github's Mac OS testing thingummy is going to be upgraded to XCode 12 next week, but for now it's using v11.

-- 
David Cantrell | Cake Smuggler Extraordinaire

Should we wait before releasing?

Thanks

I tested the patch by failing to build IP::World 0.40 without the patch, and then successfully building it with the patch applied to EU::CBuilder, so I'm confident that it works.

Normally I'd suggest uploading a trial version of EU::CB to the CPAN and asking the CPAN-testers to have at it, but the problem here is that modules fail to build at all, not that they fail tests, and the CPAN-testers generally don't report build failures as that would lead to waaaaay too many false positives due to missing libraries and the like.

-- 
David Cantrell