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

[Mariya Podchishchaeva via cfe-commits]

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@@ -250,3 +250,35 @@
 
 #if __has_embed("") // expected-error {{empty filename}}
 #endif
+
+// expected-error at +9 {{unterminated conditional directive}}
+// expected-error at +13 {{unterminated conditional directive}}
+// expected-error at +17 {{unterminated conditional directive}}
+// expected-error at +21 {{unterminated conditional directive}}
+// expected-error at +25 {{unterminated conditional directive}}
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Fznamznon wrote:

Are you saying that an invalid directive affects the parsing of `// expected-error` comments making the test not really testing anything and we avoid this problem by putting each failing directive to a separate file?

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