[clang] [clang][Modules] Permit Link Declarations in Submodule Declarations in Module Maps (PR #156377)

[Qiongsi Wu via cfe-commits]

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@@ -915,8 +915,10 @@ def err_mmap_expected_attribute : Error<"expected an attribute name">;
 def warn_mmap_link_redeclaration : Warning<"redeclaration of link library '%0'">,
   InGroup<DiagGroup<"module-link-redeclaration">>, DefaultError;
 def note_mmap_prev_link_declaration : Note<"previously declared here">;
-def err_mmap_submodule_link_decl
-    : Error<"link declaration is not allowed in submodules">;
+def warn_mmap_submodule_link_decl
+    : Warning<"link declaration is not allowed in submodules">,
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qiongsiwu wrote:

The error check has been removed.

https://github.com/llvm/llvm-project/pull/156377