[clang] [clang] Don't crash in invalid #module directive (PR #208695)

[Shafik Yaghmour via cfe-commits]

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@@ -1455,10 +1455,11 @@ void Preprocessor::HandleDirective(Token &Result) {
       return HandlePragmaDirective({PIK_HashPragma, Introducer.getLocation()});
     case tok::pp_module:
     case tok::pp___preprocessed_module:
-      return HandleCXXModuleDirective(Result);
+      if (Introducer.isModuleContextualKeyword())
+        return HandleCXXModuleDirective(Result);
+      break;
     case tok::pp___preprocessed_import:
       return HandleCXXImportDirective(Result);
-    // GNU Extensions.
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shafik wrote:

I guess the comment was incorrect in the current spot?

https://github.com/llvm/llvm-project/pull/208695