[clang-tidy] Added misc-move-const-arg docs.

llvm-svn: 267587

clang-tools-extra/docs/clang-tidy/checks/list.rst

@@ -61,6 +61,7 @@ Clang-Tidy Checks
    misc-macro-parentheses
    misc-macro-repeated-side-effects
    misc-misplaced-widening-cast
+   misc-move-const-arg
    misc-move-constructor-init
    misc-multiple-statement-macro
    misc-new-delete-overloads
@@ -76,7 +77,7 @@ Clang-Tidy Checks
    misc-string-literal-with-embedded-nul
    misc-suspicious-missing-comma
    misc-suspicious-semicolon
-   misc-suspicious-string-compare   
+   misc-suspicious-string-compare
    misc-swapped-arguments
    misc-throw-by-value-catch-by-reference
    misc-undelegated-constructor

clang-tools-extra/docs/clang-tidy/checks/misc-move-const-arg.rst

@@ -0,0 +1,15 @@
+.. title:: clang-tidy - misc-move-const-arg
+
+misc-move-const-arg
+===================
+
+The check warns if the result of ``std::move(x)`` is bound to a constant
+reference argument, e.g.:
+
+.. code:: c++
+
+  void f(const string&);
+  void g() {
+    string s;
+    F(std::move(s));  // Warning here. std::move() is not moving anything.
+  }