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| // RUN: %clang_cc1 -fsyntax-only -Wredundant-move -std=c++11 -verify %s
// RUN: %clang_cc1 -fsyntax-only -Wredundant-move -std=c++11 -fdiagnostics-parseable-fixits %s 2>&1 | FileCheck %s
// RUN: %clang_cc1 -fsyntax-only -std=c++11 %s -ast-dump | FileCheck %s --check-prefix=CHECK-AST
// definitions for std::move
namespace std {
inline namespace foo {
template <class T> struct remove_reference { typedef T type; };
template <class T> struct remove_reference<T&> { typedef T type; };
template <class T> struct remove_reference<T&&> { typedef T type; };
template <class T> typename remove_reference<T>::type &&move(T &&t);
}
}
// test1 and test2 should not warn until after implementation of DR1579.
struct A {};
struct B : public A {};
A test1(B b1) {
B b2;
return b1;
return b2;
return std::move(b1);
return std::move(b2);
}
struct C {
C() {}
C(A) {}
};
C test2(A a1, B b1) {
A a2;
B b2;
return a1;
return a2;
return b1;
return b2;
return std::move(a1);
return std::move(a2);
return std::move(b1);
return std::move(b2);
}
// Copy of tests above with types changed to reference types.
A test3(B& b1) {
B& b2 = b1;
return b1;
return b2;
return std::move(b1);
return std::move(b2);
}
C test4(A& a1, B& b1) {
A& a2 = a1;
B& b2 = b1;
return a1;
return a2;
return b1;
return b2;
return std::move(a1);
return std::move(a2);
return std::move(b1);
return std::move(b2);
}
// PR23819, case 2
struct D {};
D test5(D d) {
return d;
// Verify the implicit move from the AST dump
// CHECK-AST: ReturnStmt{{.*}}line:[[@LINE-2]]
// CHECK-AST-NEXT: CXXConstructExpr{{.*}}D{{.*}}void (D &&)
// CHECK-AST-NEXT: ImplicitCastExpr
// CHECK-AST-NEXT: DeclRefExpr{{.*}}ParmVar{{.*}}'d'
return std::move(d);
// expected-warning@-1{{redundant move in return statement}}
// expected-note@-2{{remove std::move call here}}
// CHECK: fix-it:"{{.*}}":{[[@LINE-3]]:10-[[@LINE-3]]:20}:""
// CHECK: fix-it:"{{.*}}":{[[@LINE-4]]:21-[[@LINE-4]]:22}:""
}
namespace templates {
struct A {};
struct B { B(A); };
// Warn once here since the type is not dependent.
template <typename T>
A test1(A a) {
return std::move(a);
// expected-warning@-1{{redundant move in return statement}}
// expected-note@-2{{remove std::move call here}}
// CHECK: fix-it:"{{.*}}":{[[@LINE-3]]:12-[[@LINE-3]]:22}:""
// CHECK: fix-it:"{{.*}}":{[[@LINE-4]]:23-[[@LINE-4]]:24}:""
}
void run_test1() {
test1<A>(A());
test1<B>(A());
}
// T1 and T2 may not be the same, the warning may not always apply.
template <typename T1, typename T2>
T1 test2(T2 t) {
return std::move(t);
}
void run_test2() {
test2<A, A>(A());
test2<B, A>(A());
}
}
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