[llvm] [Flang-RT] Do not use Apple-specific libdir scheme (PR #151954)

[Leandro Lupori via llvm-commits]

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@@ -34,14 +34,8 @@
 function (get_toolchain_library_subdir outvar)
   set(outval "lib")
 
-  if (APPLE)
-    # Required to be "darwin" for MachO toolchain.
-    get_toolchain_os_dirname(os_dirname)
-    set(outval "${outval}/${os_dirname}")
-  else ()
-    get_toolchain_arch_dirname(arch_dirname)
-    set(outval "${outval}/${arch_dirname}")
-  endif ()
+  get_toolchain_arch_dirname(arch_dirname)
+  set(outval "${outval}/${arch_dirname}")
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luporl wrote:

On my machine, both compiler-rt and flang-rt libraries are installed into `<install_dir>/lib/clang/22/lib/darwin`.

IIUC, this change would make flang-rt libraries be installed in a new directory, `<install_dir>/lib/clang/22/lib/darwin/<target>`, right?
Wouldn't it be better to make flang look for its libraries in the same path as compiler-rt?

https://github.com/llvm/llvm-project/pull/151954