[libcxx-commits] [libcxx] [RFC][libc++] Install modules. (PR #75741)

[Louis Dionne via libcxx-commits]

================
@@ -424,6 +428,8 @@ set(LIBCXX_INSTALL_INCLUDE_DIR "${CMAKE_INSTALL_INCLUDEDIR}/c++/v1" CACHE STRING
     "Path where target-agnostic libc++ headers should be installed.")
 set(LIBCXX_INSTALL_RUNTIME_DIR "${CMAKE_INSTALL_BINDIR}" CACHE STRING
     "Path where built libc++ runtime libraries should be installed.")
+set(LIBCXX_INSTALL_MODULE_DIR "${CMAKE_INSTALL_INCLUDEDIR}/../modules/c++/v1" CACHE STRING
----------------
ldionne wrote:

@jwakely What do you think about this? Any opinion? This path technically doesn't matter because it should always be extracted from the JSON file, but it would be nice if both GCC and Clang had semi-consistent paths.

The JSON file itself is always going to be next to the dylib in  e.g.`$prefix/usr/lib/libc++.module.json` (and in theory always accessed via something like `clang -print-file-name=libc++.module.json`).

https://github.com/llvm/llvm-project/pull/75741