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- Finish combining into a single matcher
- Rename option and add docs


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D141569/new/

https://reviews.llvm.org/D141569

Files:
  clang-tools-extra/clang-tidy/cppcoreguidelines/CMakeLists.txt
  clang-tools-extra/clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp
  
clang-tools-extra/clang-tidy/cppcoreguidelines/RvalueReferenceParamNotMovedCheck.cpp
  
clang-tools-extra/clang-tidy/cppcoreguidelines/RvalueReferenceParamNotMovedCheck.h
  clang-tools-extra/docs/ReleaseNotes.rst
  
clang-tools-extra/docs/clang-tidy/checks/cppcoreguidelines/rvalue-reference-param-not-moved.rst
  clang-tools-extra/docs/clang-tidy/checks/list.rst
  
clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/rvalue-reference-param-not-moved.cpp

Index: clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/rvalue-reference-param-not-moved.cpp
===================================================================
--- /dev/null
+++ clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/rvalue-reference-param-not-moved.cpp
@@ -0,0 +1,331 @@
+// RUN: %check_clang_tidy -std=c++11 %s cppcoreguidelines-rvalue-reference-param-not-moved %t -- \
+// RUN: -config="{CheckOptions: [{key: cppcoreguidelines-rvalue-reference-param-not-moved.AllowAnySubExpr, value: true},{key: cppcoreguidelines-rvalue-reference-param-not-moved.IgnoreUnnamedParams, value: true}]}" -- -fno-delayed-template-parsing
+// RUN: %check_clang_tidy -check-suffix=,CXX14 -std=c++14 %s cppcoreguidelines-rvalue-reference-param-not-moved %t -- -- -fno-delayed-template-parsing
+// RUN: %check_clang_tidy -check-suffix=,NOSUBEXPR -std=c++11 %s cppcoreguidelines-rvalue-reference-param-not-moved %t -- \
+// RUN: -config="{CheckOptions: [{key: cppcoreguidelines-rvalue-reference-param-not-moved.AllowAnySubExpr, value: false},{key: cppcoreguidelines-rvalue-reference-param-not-moved.IgnoreUnnamedParams, value: true}]}" -- -fno-delayed-template-parsing
+// RUN: %check_clang_tidy -check-suffix=,UNNAMED -std=c++11 %s cppcoreguidelines-rvalue-reference-param-not-moved %t -- -- -fno-delayed-template-parsing
+
+// NOLINTBEGIN
+namespace std {
+template <typename>
+struct remove_reference;
+
+template <typename _Tp> struct remove_reference { typedef _Tp type; };
+template <typename _Tp> struct remove_reference<_Tp&> { typedef _Tp type; };
+template <typename _Tp> struct remove_reference<_Tp&&> { typedef _Tp type; };
+
+template <typename _Tp>
+constexpr typename std::remove_reference<_Tp>::type &&move(_Tp &&__t) noexcept;
+
+template <typename _Tp>
+constexpr _Tp &&
+forward(typename remove_reference<_Tp>::type &__t) noexcept;
+
+}
+// NOLINTEND
+
+struct Obj {
+  Obj();
+  Obj(const Obj&);
+  Obj& operator=(const Obj&);
+  Obj(Obj&&);
+  Obj& operator=(Obj&&);
+  void member() const;
+};
+
+void consumes_object(Obj);
+
+void never_moves_param(Obj&& o) {
+  // CHECK-MESSAGES: :[[@LINE-1]]:30: warning: rvalue reference parameter 'o' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+  o.member();
+}
+
+void just_a_declaration(Obj&& o);
+
+void copies_object(Obj&& o) {
+  // CHECK-MESSAGES: :[[@LINE-1]]:26: warning: rvalue reference parameter 'o' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+  Obj copy = o;
+}
+
+template <typename T>
+void never_moves_param_template(Obj&& o, T t) {
+  // CHECK-MESSAGES: :[[@LINE-1]]:39: warning: rvalue reference parameter 'o' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+  o.member();
+}
+
+void never_moves_params(Obj&& o1, Obj&& o2) {
+  // CHECK-MESSAGES: :[[@LINE-1]]:31: warning: rvalue reference parameter 'o1' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+  // CHECK-MESSAGES: :[[@LINE-2]]:41: warning: rvalue reference parameter 'o2' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+}
+
+void never_moves_some_params(Obj&& o1, Obj&& o2) {
+  // CHECK-MESSAGES: :[[@LINE-1]]:36: warning: rvalue reference parameter 'o1' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+
+  Obj other{std::move(o2)};
+}
+
+void never_moves_unnamed(Obj&&) {}
+// CHECK-MESSAGES-UNNAMED: :[[@LINE-1]]:31: warning: rvalue reference parameter '' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+// CHECK-MESSAGES-CXX14: :[[@LINE-2]]:31: warning: rvalue reference parameter '' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+
+void never_moves_mixed(Obj o1, Obj&& o2) {
+  // CHECK-MESSAGES: :[[@LINE-1]]:38: warning: rvalue reference parameter 'o2' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+}
+
+void lambda_captures_parameter_as_value(Obj&& o) {
+  auto f = [o]() {
+    consumes_object(std::move(o));
+  };
+  // CHECK-MESSAGES: :[[@LINE-4]]:47: warning: rvalue reference parameter 'o' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+}
+
+void lambda_captures_parameter_as_value_nested(Obj&& o) {
+  // CHECK-MESSAGES: :[[@LINE-1]]:54: warning: rvalue reference parameter 'o' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+  auto f = [&o]() {
+    auto f_nested = [o]() {
+      consumes_object(std::move(o));
+    };
+  };
+  auto f2 = [o]() {
+    auto f_nested = [&o]() {
+      consumes_object(std::move(o));
+    };
+  };
+  auto f3 = [o]() {
+    auto f_nested = [&o]() {
+      auto f_nested_inner = [&o]() {
+        consumes_object(std::move(o));
+      };
+    };
+  };
+  auto f4 = [&o]() {
+    auto f_nested = [&o]() {
+      auto f_nested_inner = [o]() {
+        consumes_object(std::move(o));
+      };
+    };
+  };
+}
+
+void misc_lambda_checks() {
+  auto never_moves = [](Obj&& o1) {
+    Obj other{o1};
+  };
+  // CHECK-MESSAGES: :[[@LINE-3]]:31: warning: rvalue reference parameter 'o1' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+
+#if __cplusplus >= 201402L
+  auto never_moves_with_auto_param = [](Obj&& o1, auto& v) {
+    Obj other{o1};
+  };
+  // CHECK-MESSAGES-CXX14: :[[@LINE-3]]:47: warning: rvalue reference parameter 'o1' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+#endif
+}
+
+template <typename T>
+void forwarding_ref(T&& t) {
+  t.member();
+}
+
+template <typename T>
+void forwarding_ref_forwarded(T&& t) {
+  forwarding_ref(std::forward<T>(t));
+}
+
+template <typename... Ts>
+void type_pack(Ts&&... ts) {
+  (forwarding_ref(std::forward<Ts>(ts)), ...);
+}
+
+void call_forwarding_functions() {
+  Obj o;
+
+  forwarding_ref(Obj{});
+  type_pack(Obj{});
+  type_pack(Obj{}, o);
+  type_pack(Obj{}, Obj{});
+}
+
+void moves_parameter(Obj&& o) {
+  Obj moved = std::move(o);
+}
+
+void moves_parameter_extra_parens(Obj&& o) {
+  Obj moved = std::move((o));
+}
+
+template <typename T1, typename T2>
+struct mypair {
+  T1 first;
+  T2 second;
+};
+
+void moves_member_of_parameter(mypair<Obj, Obj>&& pair) {
+  // CHECK-MESSAGES-NOSUBEXPR: :[[@LINE-1]]:51: warning: rvalue reference parameter 'pair' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+  // CHECK-MESSAGES-UNNAMED: :[[@LINE-2]]:51: warning: rvalue reference parameter 'pair' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+  // CHECK-MESSAGES-CXX14: :[[@LINE-3]]:51: warning: rvalue reference parameter 'pair' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+  Obj a = std::move(pair.first);
+  Obj b = std::move(pair.second);
+}
+
+template <typename T>
+struct myoptional {
+  T& operator*() &;
+  T&& operator*() &&;
+};
+
+void moves_deref_optional(myoptional<Obj>&& opt) {
+  // CHECK-MESSAGES-NOSUBEXPR: :[[@LINE-1]]:45: warning: rvalue reference parameter 'opt' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+  // CHECK-MESSAGES-UNNAMED: :[[@LINE-2]]:45: warning: rvalue reference parameter 'opt' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+  // CHECK-MESSAGES-CXX14: :[[@LINE-3]]:45: warning: rvalue reference parameter 'opt' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+  Obj other = std::move(*opt);
+}
+
+void moves_optional_then_deref_resulting_rvalue(myoptional<Obj>&& opt) {
+  Obj other = *std::move(opt);
+}
+
+void pass_by_lvalue_reference(Obj& o) {
+  o.member();
+}
+
+void pass_by_value(Obj o) {
+  o.member();
+}
+
+void pass_by_const_lvalue_reference(const Obj& o) {
+  o.member();
+}
+
+void pass_by_const_lvalue_reference(const Obj&& o) {
+  o.member();
+}
+
+void lambda_captures_parameter_as_reference(Obj&& o) {
+  auto f = [&o]() {
+    consumes_object(std::move(o));
+  };
+}
+
+void lambda_captures_parameter_as_reference_nested(Obj&& o) {
+  auto f = [&o]() {
+    auto f_nested = [&o]() {
+      auto f_nested2 = [&o]() {
+        consumes_object(std::move(o));
+      };
+    };
+  };
+}
+
+#if __cplusplus >= 201402L
+void lambda_captures_parameter_generalized(Obj&& o) {
+  auto f = [o = std::move(o)]() {
+    consumes_object(std::move(o));
+  };
+}
+#endif
+
+void negative_lambda_checks() {
+  auto never_moves_nested = [](Obj&& o1) {
+    auto nested = [&]() {
+      Obj other{std::move(o1)};
+    };
+  };
+
+#if __cplusplus >= 201402L
+  auto auto_lvalue_ref_param = [](auto& o1) {
+    Obj other{o1};
+  };
+
+  auto auto_forwarding_ref_param = [](auto&& o1) {
+    Obj other{o1};
+  };
+
+  auto does_move_auto_rvalue_ref_param = [](auto&& o1) {
+    Obj other{std::forward(o1)};
+  };
+#endif
+
+  auto does_move = [](Obj&& o1) {
+    Obj other{std::move(o1)};
+  };
+
+  auto not_rvalue_ref = [](Obj& o1) {
+    Obj other{std::move(o1)};
+  };
+
+  Obj local;
+  auto captures = [local]() { };
+}
+
+struct AClass {
+  void member_with_lambda_no_move(Obj&& o) {
+    // CHECK-MESSAGES: :[[@LINE-1]]:41: warning: rvalue reference parameter 'o' is never moved from inside the function body [cppcoreguidelines-rvalue-reference-param-not-moved]
+    auto captures_this = [=, this]() {
+      Obj other = std::move(o);
+    };
+  }
+  void member_with_lambda_that_moves(Obj&& o) {
+    auto captures_this = [&, this]() {
+      Obj other = std::move(o);
+    };
+  }
+};
+
+void useless_move(Obj&& o) {
+  // FIXME - The object is not actually moved from - this should probably be
+  // flagged by *some* check. Which one?
+  std::move(o);
+}
+
+template <typename>
+class TemplatedClass;
+
+template <typename T>
+void unresolved_lookup(TemplatedClass<T>&& o) {
+  TemplatedClass<T> moved = std::move(o);
+}
+
+struct DefinesMove {
+  DefinesMove(DefinesMove&& rhs) : o(std::move(rhs.o)) { }
+  DefinesMove& operator=(DefinesMove&& rhs) {
+    if (this != &rhs) {
+      o = std::move(rhs.o);
+    }
+    return *this;
+  }
+  Obj o;
+};
+
+struct DeclaresMove {
+  DeclaresMove(DeclaresMove&& rhs);
+  DeclaresMove& operator=(DeclaresMove&& rhs);
+};
+
+struct AnotherObj {
+  AnotherObj(Obj&& o) : o(std::move(o)) {}
+  AnotherObj(Obj&& o, int) { o = std::move(o); }
+  Obj o;
+};
+
+template <class T>
+struct AClassTemplate {
+  void moves(T&& t) {
+    T other = std::move(t);
+  }
+  void never_moves(T&& t) {}
+  // FIXME - 'T' is non-deduced here, and, in an instantiation of AClassTemplate,
+  // never_moves indeed is suspicious. In many cases, AClassTemplate would
+  // either have a different specialization for T being a reference or
+  // non-reference (example, std::future), or restrict AClassTemplate to only
+  // allow instantiations where 'T' is a reference or non-reference, but not
+  // both. For now, we don't flag this code.
+};
+
+void instantiate_a_class_template() {
+  Obj o;
+  AClassTemplate<Obj> withObj;
+  withObj.never_moves(std::move(o));
+
+  AClassTemplate<Obj&> withObjRef;
+  withObjRef.never_moves(o);
+}
Index: clang-tools-extra/docs/clang-tidy/checks/list.rst
===================================================================
--- clang-tools-extra/docs/clang-tidy/checks/list.rst
+++ clang-tools-extra/docs/clang-tidy/checks/list.rst
@@ -202,6 +202,7 @@
    `cppcoreguidelines-pro-type-static-cast-downcast <cppcoreguidelines/pro-type-static-cast-downcast.html>`_, "Yes"
    `cppcoreguidelines-pro-type-union-access <cppcoreguidelines/pro-type-union-access.html>`_,
    `cppcoreguidelines-pro-type-vararg <cppcoreguidelines/pro-type-vararg.html>`_,
+   `cppcoreguidelines-rvalue-reference-param-not-moved <cppcoreguidelines/rvalue-reference-param-not-moved.html>`_,
    `cppcoreguidelines-slicing <cppcoreguidelines/slicing.html>`_,
    `cppcoreguidelines-special-member-functions <cppcoreguidelines/special-member-functions.html>`_,
    `cppcoreguidelines-virtual-class-destructor <cppcoreguidelines/virtual-class-destructor.html>`_, "Yes"
Index: clang-tools-extra/docs/clang-tidy/checks/cppcoreguidelines/rvalue-reference-param-not-moved.rst
===================================================================
--- /dev/null
+++ clang-tools-extra/docs/clang-tidy/checks/cppcoreguidelines/rvalue-reference-param-not-moved.rst
@@ -0,0 +1,50 @@
+.. title:: clang-tidy - cppcoreguidelines-rvalue-reference-param-not-moved
+
+cppcoreguidelines-rvalue-reference-param-not-moved
+==================================================
+
+Warns when an rvalue reference function parameter is never moved within
+the function body.
+
+Rvalue reference parameters indicate a parameter that should be moved with
+``std::move`` from within the function body. Any such parameter that is
+never moved is confusing and potentially indicative of a buggy program.
+
+Example:
+
+.. code-block:: c++
+
+  void logic(std::string&& Input) {
+    std::string Copy(Input); // Oops - forgot to std::move
+  }
+
+Options
+-------
+
+.. option:: AllowAnyMoveExpr
+
+   If set to `true`, the check accepts ``std::move`` calls containing any
+   subexpression containing the parameter. CppCoreGuideline F.18 officially
+   mandates that the parameter itself must be moved. Default is `false`.
+
+  .. code-block:: c++
+
+    // 'p' is flagged by this check if and only if AllowAnyMoveExpr is false
+    void move_members_of(pair<Obj, Obj>&& p) {
+      pair<Obj, Obj> other;
+      other.first = std::move(p.first);
+      other.second = std::move(p.second);
+    }
+
+    // 'p' is never flagged by this check
+    void move_whole_pair(pair<Obj, Obj>&& p) {
+      pair<Obj, Obj> other = std::move(p);
+    }
+
+.. option:: IgnoreUnnamedParams
+
+   If set to `true`, the check ignores unnamed rvalue reference parameters.
+   Default is `false`.
+
+This check implements
+`CppCoreGuideline F.18 <http://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#f18-for-will-move-from-parameters-pass-by-x-and-stdmove-the-parameter>`_.
Index: clang-tools-extra/docs/ReleaseNotes.rst
===================================================================
--- clang-tools-extra/docs/ReleaseNotes.rst
+++ clang-tools-extra/docs/ReleaseNotes.rst
@@ -110,6 +110,12 @@
 
   Warns when lambda specify a capture default and capture ``this``.
 
+- New :doc:`cppcoreguidelines-rvalue-reference-param-not-moved
+  <clang-tidy/checks/cppcoreguidelines/rvalue-reference-param-not-moved>` check.
+
+  Warns when an rvalue reference function parameter is never moved within
+  the function body.
+
 - New :doc: `llvmlibc-inline-function-decl
   <clang-tidy/checks/llvmlibc/inline-function-decl>` check.
 
Index: clang-tools-extra/clang-tidy/cppcoreguidelines/RvalueReferenceParamNotMovedCheck.h
===================================================================
--- /dev/null
+++ clang-tools-extra/clang-tidy/cppcoreguidelines/RvalueReferenceParamNotMovedCheck.h
@@ -0,0 +1,38 @@
+//===--- RvalueReferenceParamNotMovedCheck.h - clang-tidy -------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CPPCOREGUIDELINES_RVALUEREFERENCEPARAMNOTMOVEDCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CPPCOREGUIDELINES_RVALUEREFERENCEPARAMNOTMOVEDCHECK_H
+
+#include "../ClangTidyCheck.h"
+
+namespace clang::tidy::cppcoreguidelines {
+
+/// Warns when an rvalue reference function parameter is never moved within
+/// the function body. This check implements CppCoreGuideline F.18.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/cppcoreguidelines/rvalue-reference-param-not-moved.html
+class RvalueReferenceParamNotMovedCheck : public ClangTidyCheck {
+public:
+  RvalueReferenceParamNotMovedCheck(StringRef Name, ClangTidyContext *Context);
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+  bool isLanguageVersionSupported(const LangOptions &LangOpts) const override {
+    return LangOpts.CPlusPlus11;
+  }
+  void storeOptions(ClangTidyOptions::OptionMap &Opts) override;
+
+private:
+  const bool AllowAnySubExpr;
+  const bool IgnoreUnnamedParams;
+};
+
+} // namespace clang::tidy::cppcoreguidelines
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CPPCOREGUIDELINES_RVALUEREFERENCEPARAMNOTMOVEDCHECK_H
Index: clang-tools-extra/clang-tidy/cppcoreguidelines/RvalueReferenceParamNotMovedCheck.cpp
===================================================================
--- /dev/null
+++ clang-tools-extra/clang-tidy/cppcoreguidelines/RvalueReferenceParamNotMovedCheck.cpp
@@ -0,0 +1,109 @@
+//===--- RvalueReferenceParamNotMovedCheck.cpp - clang-tidy ---------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "RvalueReferenceParamNotMovedCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::cppcoreguidelines {
+
+namespace {
+AST_MATCHER_P(LambdaExpr, valueCapturesVar, DeclarationMatcher, VarMatcher) {
+  return std::find_if(Node.capture_begin(), Node.capture_end(),
+                      [&](const LambdaCapture &Capture) {
+                        return Capture.capturesVariable() &&
+                               VarMatcher.matches(*Capture.getCapturedVar(),
+                                                  Finder, Builder) &&
+                               Capture.getCaptureKind() == LCK_ByCopy;
+                      }) != Node.capture_end();
+}
+AST_MATCHER_P2(Stmt, argumentOf, bool, AllowAnySubExpr, StatementMatcher, Ref) {
+  if (AllowAnySubExpr) {
+    return stmt(anyOf(Ref, hasDescendant(Ref))).matches(Node, Finder, Builder);
+  } else {
+    return Ref.matches(Node, Finder, Builder);
+  }
+}
+} // namespace
+
+void RvalueReferenceParamNotMovedCheck::registerMatchers(MatchFinder *Finder) {
+  auto ToParam = hasAnyParameter(parmVarDecl(equalsBoundNode("param")));
+
+  StatementMatcher MoveCallMatcher =
+      callExpr(
+          anyOf(callee(functionDecl(hasName("::std::move"))),
+                callee(unresolvedLookupExpr(hasAnyDeclaration(
+                    namedDecl(hasUnderlyingDecl(hasName("::std::move"))))))),
+          argumentCountIs(1),
+          hasArgument(
+              0, argumentOf(
+                     AllowAnySubExpr,
+                     declRefExpr(to(equalsBoundNode("param"))).bind("ref"))),
+          unless(hasAncestor(
+              lambdaExpr(hasDescendant(declRefExpr(equalsBoundNode("ref"))),
+                         valueCapturesVar(equalsBoundNode("param"))))))
+          .bind("move-call");
+
+  Finder->addMatcher(
+      parmVarDecl(
+          parmVarDecl(hasType(type(rValueReferenceType()))).bind("param"),
+          parmVarDecl(
+              unless(hasType(references(qualType(anyOf(
+                  isConstQualified(),
+                  templateTypeParmType(hasDeclaration(templateTypeParmDecl())),
+                  substTemplateTypeParmType()))))),
+              anyOf(
+                  hasAncestor(compoundStmt(hasParent(lambdaExpr(
+                      has(cxxRecordDecl(
+                          has(cxxMethodDecl(ToParam, hasName("operator()"))))),
+                      optionally(hasDescendant(MoveCallMatcher)))))),
+                  hasAncestor(cxxConstructorDecl(
+                      ToParam, isDefinition(), unless(isMoveConstructor()),
+                      optionally(hasDescendant(MoveCallMatcher)))),
+                  hasAncestor(functionDecl(
+                      unless(cxxConstructorDecl()), ToParam,
+                      unless(cxxMethodDecl(isMoveAssignmentOperator())),
+                      hasBody(optionally(hasDescendant(MoveCallMatcher)))))))),
+      this);
+}
+
+void RvalueReferenceParamNotMovedCheck::check(
+    const MatchFinder::MatchResult &Result) {
+  const auto *Param = Result.Nodes.getNodeAs<ParmVarDecl>("param");
+
+  if (!Param)
+    return;
+
+  if (IgnoreUnnamedParams && Param->getName().empty())
+    return;
+
+  const auto *MoveCall = Result.Nodes.getNodeAs<CallExpr>("move-call");
+  if (!MoveCall) {
+    diag(Param->getLocation(),
+         "rvalue reference parameter %0 is never moved from "
+         "inside the function body")
+        << Param;
+  }
+}
+
+RvalueReferenceParamNotMovedCheck::RvalueReferenceParamNotMovedCheck(
+    StringRef Name, ClangTidyContext *Context)
+    : ClangTidyCheck(Name, Context),
+      AllowAnySubExpr(Options.getLocalOrGlobal("AllowAnySubExpr", false)),
+      IgnoreUnnamedParams(
+          Options.getLocalOrGlobal("IgnoreUnnamedParams", false)) {}
+
+void RvalueReferenceParamNotMovedCheck::storeOptions(
+    ClangTidyOptions::OptionMap &Opts) {
+  Options.store(Opts, "AllowAnySubExpr", AllowAnySubExpr);
+  Options.store(Opts, "IgnoreUnnamedParams", IgnoreUnnamedParams);
+}
+
+} // namespace clang::tidy::cppcoreguidelines
Index: clang-tools-extra/clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp
===================================================================
--- clang-tools-extra/clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp
+++ clang-tools-extra/clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp
@@ -37,6 +37,7 @@
 #include "ProTypeStaticCastDowncastCheck.h"
 #include "ProTypeUnionAccessCheck.h"
 #include "ProTypeVarargCheck.h"
+#include "RvalueReferenceParamNotMovedCheck.h"
 #include "SlicingCheck.h"
 #include "SpecialMemberFunctionsCheck.h"
 #include "VirtualClassDestructorCheck.h"
@@ -101,6 +102,8 @@
         "cppcoreguidelines-pro-type-union-access");
     CheckFactories.registerCheck<ProTypeVarargCheck>(
         "cppcoreguidelines-pro-type-vararg");
+    CheckFactories.registerCheck<RvalueReferenceParamNotMovedCheck>(
+        "cppcoreguidelines-rvalue-reference-param-not-moved");
     CheckFactories.registerCheck<SpecialMemberFunctionsCheck>(
         "cppcoreguidelines-special-member-functions");
     CheckFactories.registerCheck<SlicingCheck>("cppcoreguidelines-slicing");
Index: clang-tools-extra/clang-tidy/cppcoreguidelines/CMakeLists.txt
===================================================================
--- clang-tools-extra/clang-tidy/cppcoreguidelines/CMakeLists.txt
+++ clang-tools-extra/clang-tidy/cppcoreguidelines/CMakeLists.txt
@@ -28,6 +28,7 @@
   ProTypeStaticCastDowncastCheck.cpp
   ProTypeUnionAccessCheck.cpp
   ProTypeVarargCheck.cpp
+  RvalueReferenceParamNotMovedCheck.cpp
   SlicingCheck.cpp
   SpecialMemberFunctionsCheck.cpp
   VirtualClassDestructorCheck.cpp
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