[clang] Add Clang attribute to ensure that fields are initialized explicitly (PR #102040)

[via cfe-commits]

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@@ -2331,6 +2335,9 @@ def err_init_reference_member_uninitialized : Error<
   "reference member of type %0 uninitialized">;
 def note_uninit_reference_member : Note<
   "uninitialized reference member is here">;
+def warn_field_requires_explicit_init : Warning<
+  "field %select{%1|in %1}0 is not explicitly initialized, but was marked as "
+  "requiring explicit initialization">, InGroup<UninitializedExplicitInit>;
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higher-performance wrote:

Done.

https://github.com/llvm/llvm-project/pull/102040