[libcxx-commits] [libcxx] [libc++][modules] Adds std.compat module. (PR #71438)

[Louis Dionne via libcxx-commits]

================
@@ -67,3 +67,17 @@ if (
         "%{link_flags}",
         os.path.join(build, "libc++std.a"),
     )
+
+    config.substitutions = appendToSubstitution(
+        config.substitutions,
+        "%{compile_flags}",
+        "-fprebuilt-module-path="
+        + os.path.join(
+            config.test_exec_root, "__config_module__/CMakeFiles/std.compat.dir"
+        ),
+    )
+    config.substitutions = appendToSubstitution(
+        config.substitutions,
+        "%{link_flags}",
+        os.path.join(build, "libc++std.compat.a"),
----------------
ldionne wrote:

For a simple follow-up: I think we should really rename those `.a` libraries. I know they're just implementation details, but the names are too close to `libstdc++` which could create confusion. I would suggest instead: `libc++.std.a` and `libc++.std.compat.a`? Or maybe something else but it's worth thinking about a name that is less easily confused with `libstdc++.a`.

https://github.com/llvm/llvm-project/pull/71438