[clang] [Clang][Sema] Don't treat error-recovery dependence as genuine template dependence in ActOnTag (PR #221440)

[Anirudh Mathur via cfe-commits]

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@@ -653,8 +613,11 @@ features cannot lower the translation-unit ABI level;
   available as an identifier (e.g. `struct __make_unsigned`) was seen again
   in a token that was lexed and cached before the first occurrence was parsed.
   (#GH214128)
-- Fixed a crash when a coroutine keyword appeared inside a mem-initializer on a
-  function that is not a constructor. (#GH194298)
+
+- Fixed an assertion failure when explicitly instantiating a nested member
+  through a nested-name-specifier whose template argument was ill-formed. The
+  resulting error-recovery placeholder was being treated as a genuinely
+  dependent name instead of an already-diagnosed error. (#GH220525)
 
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anirudhmathur12 wrote:

Done!

https://github.com/llvm/llvm-project/pull/221440