[llvm-branch-commits] [libcxx] [libc++][modules] Adds module testing. (PR #76246)

[Will Hawkins via llvm-branch-commits]

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@@ -223,6 +280,12 @@ class CxxStandardLibraryTest(lit.formats.FileBasedTest):
             allows adding special compilation flags without having to use a
             .sh.cpp test, which would be more powerful but perhaps overkill.
 
+        // MODULE: std std.compat
+
+           This directive will build the required C++23 standard library
+           modules and add the provide the additional compiler flags in
+           %{module_flags}. (Libc++ offers these modules in C++20 as an
+           extenstion.)
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hawkinsw wrote:

```suggestion
           extension.)
```

https://github.com/llvm/llvm-project/pull/76246