This initial change adds the AIX configuration to run-buildbot, an AIX
CMake cache file, and appropriate compiler and linker flags for testing
AIX to the lit "from scratch" configuration files. Either of the 32-bit or 64-bit configurations
can be built by setting `OBJECT_MODE` in the build environment (as is
typical for AIX).
Reviewed By: ldionne, #libc, #libc_abi
Differential Revision: https://reviews.llvm.org/D111244
I came across an issue where since we build the library for Apple with
the install name directory being /usr/lib, which means that if we don't
run the tests with DYLD_LIBRARY_PATH, we'll end up loading the
system-provided libc++abi when running the tests. That wreaks havoc.
Instead of fixing it in the legacy config file, this commit introduces
an Apple libc++abi config file that does the right thing.
Differential Revision: https://reviews.llvm.org/D111279
David Tenty