[clang] More fixes for P3144R2 implementation (PR #149406)

[Harald van Dijk via cfe-commits]

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@@ -8392,17 +8392,19 @@ def ext_default_init_const : ExtWarn<
   "is a Microsoft extension">,
   InGroup<MicrosoftConstInit>;
 def err_delete_operand : Error<"cannot delete expression of type %0">;
+def err_delete_void_ptr_operand : Error<
+  "cannot delete expression with pointer-to-'void' type %0">;
 def ext_delete_void_ptr_operand : ExtWarn<
   "cannot delete expression with pointer-to-'void' type %0">,
   InGroup<DeleteIncomplete>;
 def err_ambiguous_delete_operand : Error<
   "ambiguous conversion of delete expression of type %0 to a pointer">;
 def warn_delete_incomplete : Warning<
-  "deleting pointer to incomplete type %0 is incompatible with C++2c"
+  "deleting pointer to incomplete %select{struct|union}0 %1 is incompatible with C++2c"
----------------
hvdijk wrote:

Done, with this update, the diagnostics are exactly as they were before. I've kept the other updates to the tests, but adjusted the message that is being checked for. If this looks okay we can just merge this. I can open a new issue or PR for the diagnostic later, but since that has proved contentious I'll make sure to write in far more detail about the different options and their advantages and disadvantages.

https://github.com/llvm/llvm-project/pull/149406