[clang-tools-extra] [clang-tidy] Add new check bugprone-tagged-union-member-count (PR #89925)

[Piotr Zegar via cfe-commits]

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@@ -129,6 +129,12 @@ New checks
   Replaces certain conditional statements with equivalent calls to
   ``std::min`` or ``std::max``.
 
+- New :doc:`bugprone-tagged-union-member-count
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PiotrZSL wrote:

move to line 119, keep in alphabetical order

https://github.com/llvm/llvm-project/pull/89925