[libcxxabi] Respect LIBCXXABI_LIBDIR_SUFFIX before an install

[bcraig]

Summary

Prior to this patch, setting LIBCXXABI_LIBDIR_SUFFIX would confuse the check-libcxxabi target. libc++abi.* would get output to lib instead of lib${LIBCXXABI_LIBDIR_SUFFIX}, but the tests would look in the suffixed directory.

Now, we match what libcxx does, and set the CMAKE_*_OUTPUT_DIRECTORY to the LIBRARY_DIR. This is also being done in the "standalone" branch, but now it is being performed in the in-tree branch as well.

[bcraig]

Prior version doesn't apply to master. The context was dirty from some unsubmitted patches.

[bcraig]

ping

[bcraig]

ping

[EricWF]

So we already do this for the standalone builds but not for in-tree builds.
Before committing please make sure to remove the code on CMakeLists.txt line 99 that does this same thing.

I'm assuming changing these CMake variables doesn't propagate upwards to other in-tree projects?

My one concern is that libc++ won't be able to find libc++abi when it's in a custom directory.
But that shouldn't cause problems unless it's made to.

After all that this LGTM.

[bcraig]

In D17410#403263, @EricWF wrote:

So we already do this for the standalone builds but not for in-tree builds.
Before committing please make sure to remove the code on CMakeLists.txt line 99 that does this same thing.

Done

I'm assuming changing these CMake variables doesn't propagate upwards to other in-tree projects?

libcxx has an almost identical line in its top level CMakeLists.txt at the same scope. Seems that if it's ok there, it should be fine here.

[bcraig]

r266611

CMakeLists.txt

 set(LIBCXXABI_BINARY_DIR  ${CMAKE_CURRENT_BINARY_DIR})
 set(LIBCXXABI_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LIBCXXABI_LIBDIR_SUFFIX})
 
+set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${LIBCXXABI_LIBRARY_DIR})
+set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${LIBCXXABI_LIBRARY_DIR})
+
 #===============================================================================
 # Setup Compiler Flags
 #===============================================================================