[libcxx-commits] [PATCH] D145798: [libc++] Disables transitive includes in library.

[Mark de Wever via Phabricator via libcxx-commits]

Mordante added a subscriber: ldionne.
Mordante added inline comments.


================
Comment at: libcxx/include/__config:278-279
+// it easier to upgrade the library to a newer language standard without build
+// errors. Since users are allowed to define _LIBCPP_REMOVE_TRANSITIVE_INCLUDES
+// it can't be set as a compiler flag in CMake.
+#  if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && defined(_LIBCPP_BUILDING_LIBRARY)
----------------
philnik wrote:
> I don't understand. Why would this make a difference whether a user sets it or not? We should be able to set this when building the library, just like we set `_LIBCPP_BUILDING_LIBRARY` (and I think we should set it in CMake).
I'm not sure whether that would break some unexpected cases where vendors do things we don't expect.
For example I know Chromium uses this option and they build their own libc++.
If @ldionne agrees with you I'm happy to move it to the CMakeLists,txt directly below where we define 
`_LIBCPP_BUILDING_LIBRARY`.


Repository:
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  https://reviews.llvm.org/D145798/new/

https://reviews.llvm.org/D145798