[PATCH] D11740: ABI versioning macros for libc++

[Eric Fiselier via cfe-commits]

EricWF added a comment.

In http://reviews.llvm.org/D11740#234552, @EricWF wrote:

> Thanks for doing all of this work. It's really appreciated.
>
> First, I don't really think we should have the notion of a "minor" ABI version. It will be hard enough to maintain 2 major versions and I don't understand what a minor ABI version buys us.


Woops, I realize now that I suggested a minor version originally. My apologies for being misleading.

One big problem with this patch is that it prevents the libc++ headers in libcxx/include from being used directly. This restriction seems artificial to me. If you want the "default" ABI configuration then you should be able to use the headers in the source tree. Only if you want some custom configuration (either the previous ABI version or _LIBCPP_ABI_UNSTABLE) should you have to use the headers in the build directory. In this case we should use the mechanism in http://reviews.llvm.org/D11963 (whatever that ends up being after review) and not add a `__config_version`.


http://reviews.llvm.org/D11740