[clang] [Clang] prevent crash on unterminated __has_embed (PR #163107)

[Aaron Ballman via cfe-commits]

================
@@ -1280,6 +1275,9 @@ EmbedResult Preprocessor::EvaluateHasEmbed(Token &Tok, IdentifierInfo *II) {
     return EmbedResult::Invalid;
   }
 
+  if (Params->UnrecognizedParams > 0)
+    return EmbedResult::NotFound;
+
----------------
AaronBallman wrote:

> From what I understand, unknown parameters don’t trigger an error

They don't for `__has_embed` but they do for `#embed`. The idea is: you can use `__has_embed` to determine whether the `#embed` directive will succeed or not; so if the parameter is unknown, `__has_embed` should return false.

https://github.com/llvm/llvm-project/pull/163107