[clang] Reapply "[C++20][Modules] Implement P1857R3 Modules Dependency Discovery" (#173130)" (PR #173789)

[via cfe-commits]

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@@ -926,14 +926,7 @@ <h2 id="cxx20">C++20 implementation status</h2>
       </tr>
       <tr>
         <td><a href="https://wg21.link/p1857r3">P1857R3</a></td>
-        <td class="partial" align="center">
-          <details>
-            <summary>Clang 21 (Partial)</summary>
-            The restriction that "[a] module directive may only appear
-            as the first preprocessing tokens in a file" is enforced
-            starting in Clang 21.
-          </details>
-        </td>
+        <td class="unreleased" align="center">Clang 22</td>
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yronglin wrote:

Done

https://github.com/llvm/llvm-project/pull/173789