Do not escape $ORIGIN at least on Android

[navytux]

Commit a83de88 ($ORIGIN escaping, 2018) added $ORIGIN/... to built DSO/Extension with the reason that

# Some versions of GCC will expand shell macros _internally_ when
# passing arguments to 'ld', and need '\$ORIGIN'.  And some versions don't,
# and fail with '\$ORIGIN'.
# Presumably this was a bug in gcc-wrapper which was fixed at some point.
#
# So what to do?
# For lack of a better idea, give both versions and hope that the non-functional
# one is really non-functional.

That does not create issues on regular Linux, but on Android it leads to the following warnings issued by system dynamic linker:

((1.venv) ) poco:~/setuptools_dso/example/src$ python -m dsodemo.cli
WARNING: linker: Warning: unable to normalize "\/data/data/com.termux/files/home/setuptools_dso/example/src/dsodemo/ext/../lib" (ignoring)
WARNING: linker: Warning: unable to normalize "\/data/data/com.termux/files/home/setuptools_dso/example/src/dsodemo/ext/../lib" (ignoring)
From foo.c
From bar.cpp

I would say the proper fix would be to drop that $ORIGIN escaping completely, but trying to preserve backward compatibility we can leave it on applied only selectively if the linker is indeed GCC. This fixes the issue on Android/Termux because there the compiler is CLang.

After this patch the warnings are gone:

((1.venv) ) poco:~/setuptools_dso/example/src$ python -m dsodemo.cli
From foo.c
From bar.cpp

/cc @mdavidsaver

[mdavidsaver]

This seems a reasonable way to handle a situation which should be increasingly historical.

[navytux]

Thanks, Michael.