[compiler-rt] [AIX][PGO] Handle atexit functions when dlclose'ing shared libraries (PR #102940)

[Rainer Orth via llvm-commits]

rorth wrote:

> @rorth thanks for looking into it. I don't have access to a solaris, if you're able to make it pass locally on a solaris system, I can help integrate the fix into the testcase (I imagine there has to be some platform specific options on the RUN command), or you can post a PR that I can test on AIX and ppc Linux for you.

You do have access to Solaris systems, actually: the GCC compile farm has both a Solaris/amd64 and a Solaris/sparcv9 system perfectly equipped to build and test LLVM.

That said, there's no need for anything target-specific AFAICS: many `compiler-rt` tests already use `-fPIC` unconditionally when building shared objects.  I'll file a PR later after testing on both Solaris and Linux/x86_64.

https://github.com/llvm/llvm-project/pull/102940