[clang-tools-extra] [clang-tidy] Added check 'bugprone-function-visibility-change' (PR #140086)

[Piotr Zegar via cfe-commits]

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@@ -0,0 +1,43 @@
+.. title:: clang-tidy - bugprone-function-visibility-change
+
+bugprone-function-visibility-change
+===================================
+
+Check changes in visibility of C++ member functions in subclasses. The check
+detects if a virtual function is overridden with a different visibility than in
+the base class declaration. Only normal functions are detected, no constructors,
+operators, conversions or other special functions.
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PiotrZSL wrote:

Source code of the check does not verify against operators, and destructors.
Probably tests are missing.

https://github.com/llvm/llvm-project/pull/140086