Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

external/llvm-project/clang-tools-extra/docs/clang-tidy/checks/performance-for-range-copy.rst

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+.. title:: clang-tidy - performance-for-range-copy
+
+performance-for-range-copy
+==========================
+
+Finds C++11 for ranges where the loop variable is copied in each iteration but
+it would suffice to obtain it by const reference.
+
+The check is only applied to loop variables of types that are expensive to copy
+which means they are not trivially copyable or have a non-trivial copy
+constructor or destructor.
+
+To ensure that it is safe to replace the copy with a const reference the
+following heuristic is employed:
+
+1. The loop variable is const qualified.
+2. The loop variable is not const, but only const methods or operators are
+   invoked on it, or it is used as const reference or value argument in
+   constructors or function calls.
+
+Options
+-------
+
+.. option:: WarnOnAllAutoCopies
+
+   When non-zero, warns on any use of `auto` as the type of the range-based for
+   loop variable. Default is `0`.