[clang] [Clang][Sema]: Allow copy constructor side effects (PR #81127)

[Aaron Ballman via cfe-commits]

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@@ -173,6 +173,10 @@ Bug Fixes in This Version
   for logical operators in C23.
   Fixes (`#64356 <https://github.com/llvm/llvm-project/issues/64356>`_).
 
+- Clang now doesn't produce false-positive warning `-Wunused-variable`
+  for variables created through copy initialization having side-effects in C++17 and later.
+  Fixes (`#79518 <https://github.com/llvm/llvm-project/issues/79518>`_).
----------------
AaronBallman wrote:

```suggestion
- Clang no longer produces a false-positive `-Wunused-variable` warning
  for variables created through copy initialization having side-effects in C++17 and later.
  Fixes (`#79518 <https://github.com/llvm/llvm-project/issues/79518>`_).
```

https://github.com/llvm/llvm-project/pull/81127