Fix build with LLD

[vimproved]

LLVM's LLD handles the -retain-symbols-file option (used by -export-symbols-regex in libtool) differently from GNU ld, causing undefined references during link. This commit removes the -export-symbols-regex option from libcalf_la_LDFLAGS since by default libtool exports all symbols anyway, so it should not be necessary.

Fixes #156.

[JohannesLorenz]

Thanks. I will probably set up a new CI for the project, and as soon as it works with your PR, I will merge it.

[JohannesLorenz]

Hi again @vimproved . I am starting to maintain CALF, and before I merge PRs, I would like to set up a CI. I have it working for GCC already (branch github-actions). What do I need to do to test your PR? Only add CC=clang CXX=clang++ to the configure step? Because I did this and it compiled on master, which somehow contradicts the reason for this PR.

[vimproved]

Hi again @vimproved . I am starting to maintain CALF, and before I merge PRs, I would like to set up a CI. I have it working for GCC already (branch github-actions). What do I need to do to test your PR? Only add CC=clang CXX=clang++ to the configure step? Because I did this and it compiled on master, which somehow contradicts the reason for this PR.

If your distro doesn't ship clang compiled to use LLD by default, then you'll need to also set LDFLAGS="-fuse-ld=lld"

[vimproved]

(also, if you're looking at merging some PRs could you potentially make a new release? it would be helpful for gentoo's packaging to not have lingering backports.)

[JohannesLorenz]

If your distro doesn't ship clang compiled to use LLD by default, then you'll need to also set LDFLAGS="-fuse-ld=lld"

Thanks, that indeed made it fail and if I used the CI like this, your PR indeed fixed the issue. I will make some more CI tests and then soon merge your PR.

(also, if you're looking at merging some PRs could you potentially make a new release? it would be helpful for gentoo's packaging to not have lingering backports.)

I can look after it. FWIR, ebuilds are inside the gentoo repo, so there are no artifacts we need to produce for gentoo? If you have any experience with artifacts for distros, it would be cool if you could name them in #335 .

[JohannesLorenz]

@vimproved I found another occurrence of -export-symbols-regex in src/Makefile.am for the UI descriptor. The new cmake based CI seems to work without it (Linux Gcc, Linux Clang, Mac, Windows), but I am not sure if the CI covers all potential issues. Can you please judge if this is safe to remove, and if yes, submit another PR for src/Makefile.am?

[vimproved]

@vimproved I found another occurrence of -export-symbols-regex in src/Makefile.am for the UI descriptor. The new cmake based CI seems to work without it (Linux Gcc, Linux Clang, Mac, Windows), but I am not sure if the CI covers all potential issues. Can you please judge if this is safe to remove, and if yes, submit another PR for src/Makefile.am?

Sure.

[JohannesLorenz]

@vimproved I just pushed #343 to remove that flag. Please feel free to review.