.gitattributes: turn off CRLF for Makefile.am

[MarcelRaad]

Otherwise, buildconf in a Windows checkout fails with:

.ibtoolize: error: AC_CONFIG_MACRO_DIRS([m4]) conflicts with ACLOCAL_AMFLAGS=-I m4

[mention-bot]

@MarcelRaad, thanks for your PR! By analyzing the history of the files in this pull request, we identified @billhoffman and @gknauf to be potential reviewers.

[jay]

? I use windows checkouts all the time with CRLF translation and I've never seen that

[MarcelRaad]

It happened for me on two machines where I had cloned the git repository in Windows and then ran buildconf from the Ubuntu bash that you can get with Windows 10.

[MarcelRaad]

The problem is briefly explained here:
http://pete.akeo.ie/2010/12/that-darn-libtoolize-acconfigmacrodirm4.html

[jay]

hm. Well I'd think if you're using Ubuntu to work on a local curl repo that's using CRLF translation you're going to run into problems. This probably isn't what you want to hear but maybe you should turn it off, reset the repo to just LF?

git config --local core.autocrlf input
git config --local core.eol lf
git rm -f --cached -r .
git clean -xdf
git reset --hard

I think turning it off for just this one file you'll run into more problems. But let's say we shut CRLF translation off for all *.am, is there any negative downside to that other than some editors won't work? Does any autotools require CRLF line endings that you know of?

With just this file changed are you able to build curl and then run the tests successfully?

[MarcelRaad]

This probably isn't what you want to hear but maybe you should turn it off, reset the repo to just LF?

Thanks, I didn't know this was possible for an existing checkout. Although it might be a bit inconvenient as I'm developing on Windows and running the tests on Linux, so I'd have to switch between line endings regularly.

I think turning it off for just this one file you'll run into more problems. But let's say we shut CRLF translation off for all *.am, is there any negative downside to that other than some editors won't work? Does any autotools require CRLF line endings that you know of?

With just this file changed are you able to build curl and then run the tests successfully?

It doesn't make a difference if Makefile.am or *.am is used. Both ways, I'm able to build and run the tests fine with a 98% success rate. But you're right, *.am would be better as it's consistent with the other entries in .gitattributes, so I've just changed to using that.

[MarcelRaad]

@jay

But let's say we shut CRLF translation off for all *.am, is there any negative downside to that other than some editors won't work? Does any autotools require CRLF line endings that you know of?

With just this file changed are you able to build curl and then run the tests successfully?

I haven't found any downsides to forcing LF for *.am files and everything works for me on Linux as well as Windows (MSYS2) with CRLF translation.
There are 5 tests failing with CRLF translation that don't fail when using only LF: 1022 1023 1135 1221 1222.
1135 fails also under Windows, the others only under Linux.
If there are no objections, I'll push this commit and look at those 5 tests later.