Add linking tests and fix macOS rpath

[traversaro]

Checklist

• Used a personal fork of the feedstock to propose changes
• Bumped the build number (if the version is unchanged)
• Reset the build number to 0 (if the version changed)
• Re-rendered with the latest conda-smithy (Use the phrase @conda-forge-admin, please rerender in a comment in this PR for automated rerendering)
• Ensured the license file is being packaged.

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[jwillemsen]

Maybe use mpc to generate the build files, see the ace examples

[traversaro]

Maybe use mpc to generate the build files, see the ace examples

I was trying to simulate the downstream users of the ACE library, for this reason I prefer to have full control (and understanding) of what the compiler is doing, as I imagine that at least some downstream uses of ACE (at least the one in YARP) do not use mpc. Indeed I was able to replicate the problem, as now the example works fine on Linux and Windows, while it fails on macOS.

[traversaro]

After a few trial and errors, I was able to fix the problem. The main problem is that the rpath option given in https://github.com/DOCGroup/ACE_TAO/blob/25f5307a46b10ebe7f26f46c006892f0e249c365/ACE/include/makeinclude/platform_macosx_yosemite.GNU#L6 specify that the install location of the library is @rpath/$@, where $@ is the name of the Make target. The problem is that the name of the target is 64/libACE.dylib, so the installed name is also expected to inside a 64 directory, that in practice does not exist. For this reason I substituted in $@ with $(notdir $@) that get just the file name out of the target name, i.e. only libACE.dylib.

[jwillemsen]

Isn’t the ‘64’ directory set through a specific environment variable which you could use?

[traversaro]

Isn’t the ‘64’ directory set through a specific environment variable which you could use?

This is a good question, for which I don't have an answer. Unfortunately the MPC/Makefile-based build system of ACE is not completely clear to me, so it is not clear how the target names are computed.

[jwillemsen]

I don’t have a mac anymore so I can’t try this, maybe you can make an issue upstream for this issue in ACE, maybe someone else with a mac can try this

[traversaro]

@conda-forge-admin, please rerender

[traversaro]

I don’t have a mac anymore so I can’t try this, maybe you can make an issue upstream for this issue in ACE, maybe someone else with a mac can try this

Ok! By the way, I tried to understand why everything was working on Homebrew (the only other package manager on which we use) and I guess there homebrew does something after the build of binaries, such as removing rpath that are pointing to non-existing directories, but this is just my wild guess.