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

[Louis Dionne via libcxx-commits]

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@@ -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 "usr/share/libc++/v1" CACHE STRING
+    "Path where target-agnostic libc++ modules should be installed.")
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ldionne wrote:

>From https://cmake.org/cmake/help/v3.28/module/GNUInstallDirs.html, I would suggest `${CMAKE_INSTALL_DATAROOTDIR}/libc++/v1`, which would be `$prefix/share/libc++/v1`. Vendors would generally set `CMAKE_INSTALL_PREFIX=/usr`, which would give `/usr/share/libc++/v1`.

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