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.