[PATCH] D48694: [libc++abi] Limit libc++ header search to specified paths

[Eric Fiselier via Phabricator via cfe-commits]

EricWF added a comment.



> For whether it makes sense to search for includes in the system path, that boils down to @ldionne's question of whether building libc++abi against a system-installed libc++ is supported. I actually don't know the answer to that myself ... @dexonsmith and @EricWF, what are your thoughts on that? The current search won't find the system-installed libc++ headers on Darwin anyway though, where they're placed in the compiler's include directory rather than a system include directory.

Building libc++abi against an installed libc++ doesn't make sense IMO, so I don't care if we try to support it. Libc++abi is a lower lever component with libc++ being built on top of it.
If you want to update libc++abi, you should be building a new libc++ as well. (Note: Using system libc++abi headers to build libc++ would make sense though).

As an aside, libc++abi should really live in the libc++ repository. That way it would always have the correct headers available. But every time I pitch that idea I get a ton of push back.


Repository:
  rCXXA libc++abi

https://reviews.llvm.org/D48694