Fix unknown argument: '-export-dynamic' on macOS

[jponf]

Issue #225

Description of changes: Add '-Wl' to instruct clang (default compiler on macOs) to forward argument to linker phase.

Testing done: Manual install via pip install . on macOS Sonoma 14.7.1 and Debian bookworm (gcc) and through the unit test with tox -e py39 -- -s -vv test/unit/test_entry_point.py::test_install_module on macOS and tox -e py310 -- -s -vv test/unit/test_entry_point.py::test_install_module on Debian.

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[jponf]

@bhaoz or @jswudi Can you please review?

[prtsh]

nit: separate out -Wl and -export-dynamic.

[prtsh]

Suggestion: explore separating out linker and compile args if any, guideline- https://setuptools.pypa.io/en/latest/userguide/ext_modules.html#compiler-and-linker-options

[jponf]

I don't understand your suggestion. The -Wl option is a comma separated list of options to forward to the linker. In the link you suggested there is an example where -Wl is joint with the option "-rpath"

then, a linker-specific option like -Wl,-rpath for each element of Extension.runtime_library_dirs,

I did some more tests, gcc accepts the stand-alone -export-dynamic but clang does not, it requires it being passed with "-Wl" to properly forward it to the linker. Additionally, separating "-Wl" and "-export-dynamic" breaks in both gcc and clang since "-Wl" alone is an unrecognized option. Finally, I've tested moving the option to runtime_library_dirs and extra_link_args and only works on the first.

If you want I could move the option to the argument runtime_library_dirs but the value would still be "-Wl,-export-dynamic". The only difference it would make is the order in which the option will be appended into the command to invoke gcc or clang. I'm ok with either change.