diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
index 44e1a60ce24..a098ae1830d 100644
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -1229,6 +1229,10 @@ Wselector
 ObjC ObjC++ Var(warn_selector) Warning
 Warn if a selector has multiple methods.
 
+Wself-move
+C++ ObjC++ Var(warn_self_move) Warning LangEnabledBy(C++ ObjC++, Wall)
+Warn when a value is moved to itself with std::move.
+
 Wsequence-point
 C ObjC C++ ObjC++ Var(warn_sequence_point) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
 Warn about possible violations of sequence point rules.
diff --git a/gcc/cp/typeck.cc b/gcc/cp/typeck.cc
index 6e4f23af982..f05913c0fac 100644
--- a/gcc/cp/typeck.cc
+++ b/gcc/cp/typeck.cc
@@ -8897,7 +8897,51 @@ cp_build_c_cast (location_t loc, tree type, tree expr,
 
   return error_mark_node;
 }
-
+
+/* Warn when a value is moved to itself with std::move.  LHS is the target,
+   RHS may be the std::move call, and LOC is the location of the whole
+   assignment.  */
+
+static void
+maybe_warn_self_move (location_t loc, tree lhs, tree rhs)
+{
+  if (!warn_self_move)
+    return;
+
+  /* C++98 doesn't know move.  */
+  if (cxx_dialect < cxx11)
+    return;
+
+  if (processing_template_decl)
+    return;
+
+  /* We're looking for *std::move<T&> ((T &) &arg), or
+     *std::move<T&> ((T &) (T *) r) if the argument it a reference.  */
+  if (!REFERENCE_REF_P (rhs)
+      || TREE_CODE (TREE_OPERAND (rhs, 0)) != CALL_EXPR)
+    return;
+  tree fn = TREE_OPERAND (rhs, 0);
+  if (!is_std_move_p (fn))
+    return;
+  tree arg = CALL_EXPR_ARG (fn, 0);
+  if (TREE_CODE (arg) != NOP_EXPR)
+    return;
+  /* Strip the (T &).  */
+  arg = TREE_OPERAND (arg, 0);
+  /* Strip the (T *) or &.  */
+  arg = TREE_OPERAND (arg, 0);
+  arg = convert_from_reference (arg);
+  /* So that we catch (i) = std::move (i);.  */
+  lhs = maybe_undo_parenthesized_ref (lhs);
+  STRIP_ANY_LOCATION_WRAPPER (lhs);
+  if (cp_tree_equal (lhs, arg))
+    {
+      auto_diagnostic_group d;
+      if (warning_at (loc, OPT_Wself_move, "moving a variable to itself"))
+	inform (loc, "remove %<std::move%> call");
+    }
+}
+
 /* For use from the C common bits.  */
 tree
 build_modify_expr (location_t location,
@@ -9101,6 +9145,8 @@ cp_build_modify_expr (location_t loc, tree lhs, enum tree_code modifycode,
 
       if (modifycode == NOP_EXPR)
 	{
+	  maybe_warn_self_move (loc, lhs, rhs);
+
 	  if (c_dialect_objc ())
 	    {
 	      result = objc_maybe_build_modify_expr (lhs, rhs);
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index f3e9429b2ca..28cf36b94c6 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -264,7 +264,7 @@ in the following sections.
 -Wreorder  -Wregister @gol
 -Wstrict-null-sentinel  -Wno-subobject-linkage  -Wtemplates @gol
 -Wno-non-template-friend  -Wold-style-cast @gol
--Woverloaded-virtual  -Wno-pmf-conversions -Wsign-promo @gol
+-Woverloaded-virtual  -Wno-pmf-conversions -Wself-move -Wsign-promo @gol
 -Wsized-deallocation  -Wsuggest-final-methods @gol
 -Wsuggest-final-types  -Wsuggest-override  @gol
 -Wno-terminate  -Wuseless-cast  -Wno-vexing-parse  @gol
@@ -5841,6 +5841,7 @@ Options} and @ref{Objective-C and Objective-C++ Dialect Options}.
 -Wreorder   @gol
 -Wrestrict   @gol
 -Wreturn-type  @gol
+-Wself-move @r{(only for C++)}  @gol
 -Wsequence-point  @gol
 -Wsign-compare @r{(only in C++)}  @gol
 -Wsizeof-array-div @gol
@@ -6826,6 +6827,26 @@ of a declaration:
 
 This warning is enabled by @option{-Wall}.
 
+@item -Wno-self-move @r{(C++ and Objective-C++ only)}
+@opindex Wself-move
+@opindex Wno-self-move
+This warning warns when a value is moved to itself with @code{std::move}.
+Such a @code{std::move} has no effect.
+
+@smallexample
+struct T @{
+@dots{}
+@};
+void fn()
+@{
+  T t;
+  @dots{}
+  t = std::move (t);
+@}
+@end smallexample
+
+This warning is enabled by @option{-Wall}.
+
 @item -Wsequence-point
 @opindex Wsequence-point
 @opindex Wno-sequence-point
diff --git a/gcc/testsuite/g++.dg/warn/Wself-move1.C b/gcc/testsuite/g++.dg/warn/Wself-move1.C
new file mode 100644
index 00000000000..4a6dbad4533
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/Wself-move1.C
@@ -0,0 +1,87 @@
+// PR c++/81159
+// { dg-do compile { target c++11 } }
+// { dg-options "-Wself-move" }
+
+// Define std::move.
+namespace std {
+  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
+    { return static_cast<typename std::remove_reference<_Tp>::type&&>(__t); }
+}
+
+int g;
+
+struct S {
+  int x;
+  S(S&& o) {
+    x = std::move (x); // { dg-warning "moving a variable to itself" }
+    x = std::move (o.x);
+    o.x = std::move (x);
+    o.x = std::move (o.x); // { dg-warning "moving a variable to itself" }
+  }
+  void foo (int x) {
+    x = std::move (x); // { dg-warning "moving a variable to itself" }
+  }
+};
+
+struct X {
+  int x;
+  X(int x) : x(std::move (x)) { }
+};
+
+struct A {};
+struct B { A a; };
+struct C { C(); ~C(); };
+struct D { D(); D(const D&); D(D&&); D& operator=(const D&); };
+
+void
+test ()
+{
+  int i = 42;
+  i = std::move (i); // { dg-warning "moving a variable to itself" }
+  (i) = std::move (i); // { dg-warning "moving a variable to itself" }
+
+  g = std::move (g); // { dg-warning "moving a variable to itself" }
+  (g) = std::move (g); // { dg-warning "moving a variable to itself" }
+
+  A a;
+  a = std::move (a); // { dg-warning "moving a variable to itself" }
+
+  B b;
+  b = std::move (b); // { dg-warning "moving a variable to itself" }
+  b.a = std::move (b.a); // { dg-warning "moving a variable to itself" }
+
+  C c;
+  c = std::move (c); // { dg-warning "moving a variable to itself" }
+  D d;
+  d = std::move (d); // { dg-warning "moving a variable to itself" }
+}
+
+template<typename T>
+void ttest ()
+{
+  T t;
+  t = std::move (t); // { dg-warning "moving a variable to itself" }
+}
+
+template void ttest<A>();
+
+void
+testref (int &r, int &&rr)
+{
+  r = std::move (r); // { dg-warning "moving a variable to itself" }
+  rr = std::move (rr); // { dg-warning "moving a variable to itself" }
+}
