Makefile clean target doesn't work with GNU make

[sten0]

Hi Paul,

While importing the latest release into Debian, I noted the clean target was broken, but I'm assuming that you don't see it because you're on macOS and are using BSD make.

This is the problem:
https://github.com/rnkn/fountain-mode/blame/f3685ac7235de79cfa9a9c84acbbe8541bcf5e25/Makefile#L60

Please let me know if you'd like to support developers who use GNU (rather than BSD) systems, as well as if you'd prefer the one-line solution that calls find, or something else.

[rnkn]

Thanks for the heads up. I've only considered the Makefile as a convenience thing for me, so portability hasn't been a huge concern, but if you have a fix, by all means!

[rnkn]

I just tested with GNU Make versions 3.81 (macOS) and 4.4.1 (gmake, MacPorts) and didn't get any errors, but if you could let me know what needs to change that would be great!

[sten0]

I just tested with GNU Make versions 3.81 (macOS) and 4.4.1 (gmake, MacPorts) and didn't get any errors, but if you could let me know what needs to change that would be great!

Hm, well, it didn't look like shell expansion last I looked...oh! I bet macOS comes with a library of convenient macro expansions that are enabled by default (I'm assuming this isn't a user config thing). I've been waiting for your reply to learn if you'd like a PR that uses native makefile (uglier, bigger, but works everywhere) or the conventional method of calling 'find' (might not work on Windows). Alternatively, if you can ant to do it yourself, there are lots of resources online about these two methods.

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[rnkn]

Yes please send a patch if it's not working for you! I think the first way, the native Makefile would be best.