Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

external/llvm-project/clang-tools-extra/docs/clang-tidy/checks/performance-move-const-arg.rst

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+.. title:: clang-tidy - performance-move-const-arg
+
+performance-move-const-arg
+==========================
+
+The check warns
+
+- if ``std::move()`` is called with a constant argument,
+
+- if ``std::move()`` is called with an argument of a trivially-copyable type,
+
+- if the result of ``std::move()`` is passed as a const reference argument.
+
+In all three cases, the check will suggest a fix that removes the
+``std::move()``.
+
+Here are examples of each of the three cases:
+
+.. code-block:: c++
+
+  const string s;
+  return std::move(s);  // Warning: std::move of the const variable has no effect
+
+  int x;
+  return std::move(x);  // Warning: std::move of the variable of a trivially-copyable type has no effect
+
+  void f(const string &s);
+  string s;
+  f(std::move(s));  // Warning: passing result of std::move as a const reference argument; no move will actually happen
+
+Options
+-------
+
+.. option:: CheckTriviallyCopyableMove
+
+   If non-zero, enables detection of trivially copyable types that do not
+   have a move constructor. Default is non-zero.