Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

external/llvm-project/clang-tools-extra/docs/clang-tidy/checks/bugprone-dangling-handle.rst

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+.. title:: clang-tidy - bugprone-dangling-handle
+
+bugprone-dangling-handle
+========================
+
+Detect dangling references in value handles like
+``std::experimental::string_view``.
+These dangling references can be a result of constructing handles from temporary
+values, where the temporary is destroyed soon after the handle is created.
+
+Examples:
+
+.. code-block:: c++
+
+  string_view View = string();  // View will dangle.
+  string A;
+  View = A + "A";  // still dangle.
+
+  vector<string_view> V;
+  V.push_back(string());  // V[0] is dangling.
+  V.resize(3, string());  // V[1] and V[2] will also dangle.
+
+  string_view f() {
+    // All these return values will dangle.
+    return string();
+    string S;
+    return S;
+    char Array[10]{};
+    return Array;
+  }
+
+Options
+-------
+
+.. option:: HandleClasses
+
+   A semicolon-separated list of class names that should be treated as handles.
+   By default only ``std::experimental::basic_string_view`` is considered.