// RUN: %clang_cc1 -analyze -analyzer-checker=alpha.cplusplus.MisusedMovedObject -std=c++11 -verify -analyzer-output=text %s namespace std { template struct remove_reference; template struct remove_reference { typedef _Tp type; }; template struct remove_reference<_Tp &> { typedef _Tp type; }; template struct remove_reference<_Tp &&> { typedef _Tp type; }; template typename remove_reference<_Tp>::type &&move(_Tp &&__t) { return static_cast::type &&>(__t); } template _Tp &&forward(typename remove_reference<_Tp>::type &__t) noexcept { return static_cast<_Tp &&>(__t); } template void swap(T &a, T &b) { T c(std::move(a)); a = std::move(b); b = std::move(c); } } // namespace std class B { public: B() = default; B(const B &) = default; B(B &&) = default; void operator=(B &&b) { return; } void foo() { return; } }; class A { int i; double d; public: B b; A(int ii = 42, double dd = 1.0) : d(dd), i(ii), b(B()) {} void moveconstruct(A &&other) { std::swap(b, other.b); std::swap(d, other.d); std::swap(i, other.i); return; } static A get() { A v(12, 13); return v; } A(A *a) { moveconstruct(std::move(*a)); } A(const A &other) : i(other.i), d(other.d), b(other.b) {} A(A &&other) : i(other.i), d(other.d), b(std::move(other.b)) { // expected-note {{'b' became 'moved-from' here}} } A(A &&other, char *k) { moveconstruct(std::move(other)); } void operator=(A &&other) { moveconstruct(std::move(other)); return; } int getI() { return i; } int foo() const; void bar() const; void reset(); void destroy(); void clear(); bool empty() const; bool isEmpty() const; operator bool() const; }; int bignum(); void moveInsideFunctionCall(A a) { A b = std::move(a); } void leftRefCall(A &a) { a.foo(); } void rightRefCall(A &&a) { a.foo(); } void constCopyOrMoveCall(const A a) { a.foo(); } void copyOrMoveCall(A a) { a.foo(); } void simpleMoveCtorTest() { A a; A b; b = std::move(a); // expected-note {{'a' became 'moved-from' here}} a.foo(); // expected-warning {{Method call on a 'moved-from' object 'a'}} expected-note {{Method call on a 'moved-from' object 'a'}} } void simpleMoveAssignementTest() { A a; A b; b = std::move(a); // expected-note {{'a' became 'moved-from' here}} a.foo(); // expected-warning {{Method call on a 'moved-from' object 'a'}} expected-note {{Method call on a 'moved-from' object 'a'}} } void moveInInitListTest() { struct S { A a; }; A a; S s{std::move(a)}; // expected-note {{'a' became 'moved-from' here}} a.foo(); // expected-warning {{Method call on a 'moved-from' object 'a'}} expected-note {{Method call on a 'moved-from' object 'a'}} } // Don't report a bug if the variable was assigned to in the meantime. void reinitializationTest(int i) { { A a; A b; b = std::move(a); a = A(); a.foo(); } { A a; if (i == 1) { // expected-note {{Assuming 'i' is not equal to 1}} expected-note {{Taking false branch}} // expected-note@-1 {{Assuming 'i' is not equal to 1}} expected-note@-1 {{Taking false branch}} A b; b = std::move(a); a = A(); } if (i == 2) { // expected-note {{Assuming 'i' is not equal to 2}} expected-note {{Taking false branch}} //expected-note@-1 {{Assuming 'i' is not equal to 2}} expected-note@-1 {{Taking false branch}} a.foo(); // no-warning } } { A a; if (i == 1) { // expected-note {{Taking false branch}} expected-note {{Taking false branch}} std::move(a); } if (i == 2) { // expected-note {{Taking false branch}} expected-note {{Taking false branch}} a = A(); a.foo(); } } // The built-in assignment operator should also be recognized as a // reinitialization. (std::move() may be called on built-in types in template // code.) { int a1 = 1, a2 = 2; std::swap(a1, a2); } // A std::move() after the assignment makes the variable invalid again. { A a; A b; b = std::move(a); a = A(); b = std::move(a); // expected-note {{'a' became 'moved-from' here}} a.foo(); // expected-warning {{Method call on a 'moved-from' object 'a'}} expected-note {{Method call on a 'moved-from' object 'a'}} } // If a path exist where we not reinitialize the variable we report a bug. { A a; A b; b = std::move(a); // expected-note {{'a' became 'moved-from' here}} if (i < 10) { // expected-note {{Assuming 'i' is >= 10}} expected-note {{Taking false branch}} a = A(); } if (i > 5) { // expected-note {{Taking true branch}} a.foo(); // expected-warning {{Method call on a 'moved-from' object 'a'}} expected-note {{Method call on a 'moved-from' object 'a'}} } } } // Using decltype on an expression is not a use. void decltypeIsNotUseTest() { A a; // A b(std::move(a)); decltype(a) other_a; // no-warning } void loopTest() { { A a; for (int i = 0; i < bignum(); i++) { // expected-note {{Loop condition is false. Execution jumps to the end of the function}} rightRefCall(std::move(a)); // no-warning } } { A a; for (int i = 0; i < 2; i++) { // expected-note {{Loop condition is true. Entering loop body}} //expected-note@-1 {{Loop condition is true. Entering loop body}} //expected-note@-2 {{Loop condition is false. Execution jumps to the end of the function}} rightRefCall(std::move(a)); // no-warning } } { A a; for (int i = 0; i < bignum(); i++) { // expected-note {{Loop condition is false. Execution jumps to the end of the function}} leftRefCall(a); // no-warning } } { A a; for (int i = 0; i < 2; i++) { // expected-note {{Loop condition is true. Entering loop body}} //expected-note@-1 {{Loop condition is true. Entering loop body}} //expected-note@-2 {{Loop condition is false. Execution jumps to the end of the function}} leftRefCall(a); // no-warning } } { A a; for (int i = 0; i < bignum(); i++) { // expected-note {{Loop condition is false. Execution jumps to the end of the function}} constCopyOrMoveCall(a); // no-warning } } { A a; for (int i = 0; i < 2; i++) { // expected-note {{Loop condition is true. Entering loop body}} //expected-note@-1 {{Loop condition is true. Entering loop body}} //expected-note@-2 {{Loop condition is false. Execution jumps to the end of the function}} constCopyOrMoveCall(a); // no-warning } } { A a; for (int i = 0; i < bignum(); i++) { // expected-note {{Loop condition is false. Execution jumps to the end of the function}} moveInsideFunctionCall(a); // no-warning } } { A a; for (int i = 0; i < 2; i++) { // expected-note {{Loop condition is true. Entering loop body}} //expected-note@-1 {{Loop condition is true. Entering loop body}} //expected-note@-2 {{Loop condition is false. Execution jumps to the end of the function}} moveInsideFunctionCall(a); // no-warning } } { A a; for (int i = 0; i < bignum(); i++) { // expected-note {{Loop condition is false. Execution jumps to the end of the function}} copyOrMoveCall(a); // no-warning } } { A a; for (int i = 0; i < 2; i++) { // expected-note {{Loop condition is true.}} //expected-note@-1 {{Loop condition is true. Entering loop body}} //expected-note@-2 {{Loop condition is false. Execution jumps to the end of the function}} copyOrMoveCall(a); // no-warning } } { A a; for (int i = 0; i < bignum(); i++) { // expected-note {{Loop condition is true. Entering loop body}} expected-note {{Loop condition is true. Entering loop body}} constCopyOrMoveCall(std::move(a)); // expected-warning {{Copying a 'moved-from' object 'a'}} expected-note {{Copying a 'moved-from' object 'a'}} // expected-note@-1 {{'a' became 'moved-from' here}} } } // Don't warn if we return after the move. { A a; for (int i = 0; i < 3; ++i) { a.bar(); if (a.foo() > 0) { A b; b = std::move(a); // no-warning return; } } } } //report a usage of a moved-from object only at the first use void uniqueTest(bool cond) { A a(42, 42.0); A b; b = std::move(a); // expected-note {{'a' became 'moved-from' here}} if (cond) { // expected-note {{Assuming 'cond' is not equal to 0}} expected-note {{Taking true branch}} a.foo(); // expected-warning {{Method call on a 'moved-from' object 'a'}} expected-note {{Method call on a 'moved-from' object 'a'}} } if (cond) { a.bar(); // no-warning } a.bar(); // no-warning } void uniqueTest2() { A a; A a1 = std::move(a); // expected-note {{'a' became 'moved-from' here}} a.foo(); // expected-warning {{Method call on a 'moved-from' object 'a'}} expected-note {{Method call on a 'moved-from' object 'a'}} A a2 = std::move(a); // no-warning a.foo(); // no-warning } // There are exceptions where we assume in general that the method works fine //even on moved-from objects. void moveSafeFunctionsTest() { A a; A b = std::move(a); // expected-note {{'a' became 'moved-from' here}} a.empty(); // no-warning a.isEmpty(); // no-warning (void)a; // no-warning (bool)a; // expected-warning {{expression result unused}} a.foo(); // expected-warning {{Method call on a 'moved-from' object 'a'}} expected-note {{Method call on a 'moved-from' object 'a'}} } void moveStateResetFunctionsTest() { { A a; A b = std::move(a); a.reset(); // no-warning a.foo(); // no-warning } { A a; A b = std::move(a); a.destroy(); // no-warning a.foo(); // no-warning } { A a; A b = std::move(a); a.clear(); // no-warning a.foo(); // no-warning } } // Moves or uses that occur as part of template arguments. template class ClassTemplate { public: void foo(A a); }; template void functionTemplate(A a); void templateArgIsNotUseTest() { { // A pattern like this occurs in the EXPECT_EQ and ASSERT_EQ macros in // Google Test. A a; ClassTemplate().foo(std::move(a)); // no-warning } { A a; functionTemplate(std::move(a)); // no-warning } } // Moves of global variables are not reported. A global_a; void globalVariablesTest() { std::move(global_a); global_a.foo(); // no-warning } // Moves of member variables. class memberVariablesTest { A a; static A static_a; void f() { A b; b = std::move(a); // expected-note {{'a' became 'moved-from' here}} a.foo(); // expected-warning {{Method call on a 'moved-from' object}} expected-note {{Method call on a 'moved-from' object 'a'}} b = std::move(static_a); // expected-note {{'static_a' became 'moved-from' here}} static_a.foo(); // expected-warning {{Method call on a 'moved-from' object 'static_a'}} expected-note {{Method call on a 'moved-from' object 'static_a'}} } }; void PtrAndArrayTest() { A *Ptr = new A(1, 1.5); A Arr[10]; Arr[2] = std::move(*Ptr); // expected-note {{Became 'moved-from' here}} (*Ptr).foo(); // expected-warning {{Method call on a 'moved-from' object}} expected-note {{Method call on a 'moved-from' object}} Ptr = &Arr[1]; Arr[3] = std::move(Arr[1]); // expected-note {{Became 'moved-from' here}} Ptr->foo(); // expected-warning {{Method call on a 'moved-from' object}} expected-note {{Method call on a 'moved-from' object}} Arr[3] = std::move(Arr[2]); // expected-note {{Became 'moved-from' here}} Arr[2].foo(); // expected-warning {{Method call on a 'moved-from' object}} expected-note {{Method call on a 'moved-from' object}} Arr[2] = std::move(Arr[3]); // reinitialization Arr[2].foo(); // no-warning } void exclusiveConditionsTest(bool cond) { A a; if (cond) { A b; b = std::move(a); } if (!cond) { a.bar(); // no-warning } } void differentBranchesTest(int i) { // Don't warn if the use is in a different branch from the move. { A a; if (i > 0) { // expected-note {{Assuming 'i' is > 0}} expected-note {{Taking true branch}} A b; b = std::move(a); } else { a.foo(); // no-warning } } // Same thing, but with a ternary operator. { A a, b; i > 0 ? (void)(b = std::move(a)) : a.bar(); // no-warning // expected-note {{'?' condition is true}} } // A variation on the theme above. { A a; a.foo() > 0 ? a.foo() : A(std::move(a)).foo(); // expected-note {{Assuming the condition is false}} expected-note {{'?' condition is false}} } // Same thing, but with a switch statement. { A a, b; switch (i) { // expected-note {{Control jumps to 'case 1:' at line 448}} case 1: b = std::move(a); // no-warning break; // expected-note {{Execution jumps to the end of the function}} case 2: a.foo(); // no-warning break; } } // However, if there's a fallthrough, we do warn. { A a, b; switch (i) { // expected-note {{Control jumps to 'case 1:' at line 460}} case 1: b = std::move(a); // expected-note {{'a' became 'moved-from' here}} case 2: a.foo(); // expected-warning {{Method call on a 'moved-from' object}} expected-note {{Method call on a 'moved-from' object 'a'}} break; } } } void tempTest() { A a = A::get(); A::get().foo(); // no-warning for (int i = 0; i < bignum(); i++) { A::get().foo(); // no-warning } } void interFunTest1(A &a) { a.bar(); // expected-warning {{Method call on a 'moved-from' object 'a'}} expected-note {{Method call on a 'moved-from' object 'a'}} } void interFunTest2() { A a; A b; b = std::move(a); // expected-note {{'a' became 'moved-from' here}} interFunTest1(a); // expected-note {{Calling 'interFunTest1'}} } void foobar(A a, int i); void foobar(int i, A a); void paramEvaluateOrderTest() { A a; foobar(std::move(a), a.getI()); // expected-warning {{Method call on a 'moved-from' object 'a'}} expected-note {{Method call on a 'moved-from' object 'a'}} // expected-note@-1 {{'a' became 'moved-from' here}} //FALSE NEGATIVE since parameters evaluate order is undefined foobar(a.getI(), std::move(a)); //no-warning } void not_known(A &a); void not_known(A *a); void regionAndPointerEscapeTest() { { A a; A b; b = std::move(a); not_known(a); a.foo(); //no-warning } { A a; A b; b = std::move(a); not_known(&a); a.foo(); // no-warning } } // A declaration statement containing multiple declarations sequences the // initializer expressions. void declarationSequenceTest() { { A a; A a1 = a, a2 = std::move(a); // no-warning } { A a; A a1 = std::move(a), a2 = a; // expected-warning {{Copying a 'moved-from' object 'a'}} expected-note {{Copying a 'moved-from' object 'a'}} // expected-note@-1 {{'a' became 'moved-from' here}} } } // The logical operators && and || sequence their operands. void logicalOperatorsSequenceTest() { { A a; if (a.foo() > 0 && A(std::move(a)).foo() > 0) { // expected-note {{Assuming the condition is false}} expected-note {{Assuming the condition is false}} // expected-note@-1 {{Left side of '&&' is false}} expected-note@-1 {{Left side of '&&' is false}} //expected-note@-2 {{Taking false branch}} expected-note@-2 {{Taking false branch}} A().bar(); } } // A variation: Negate the result of the && (which pushes the && further down // into the AST). { A a; if (!(a.foo() > 0 && A(std::move(a)).foo() > 0)) { // expected-note {{Assuming the condition is false}} expected-note {{Assuming the condition is false}} // expected-note@-1 {{Left side of '&&' is false}} expected-note@-1 {{Left side of '&&' is false}} // expected-note@-2 {{Taking true branch}} expected-note@-2 {{Taking true branch}} A().bar(); } } { A a; if (A(std::move(a)).foo() > 0 && a.foo() > 0) { // expected-warning {{Method call on a 'moved-from' object 'a'}} expected-note {{Method call on a 'moved-from' object 'a'}} // expected-note@-1 {{'a' became 'moved-from' here}} expected-note@-1 {{Assuming the condition is true}} expected-note@-1 {{Assuming the condition is false}} // expected-note@-2 {{Left side of '&&' is false}} expected-note@-2 {{Left side of '&&' is true}} // expected-note@-3 {{Taking false branch}} A().bar(); } } { A a; if (a.foo() > 0 || A(std::move(a)).foo() > 0) { // expected-note {{Assuming the condition is true}} //expected-note@-1 {{Left side of '||' is true}} //expected-note@-2 {{Taking true branch}} A().bar(); } } { A a; if (A(std::move(a)).foo() > 0 || a.foo() > 0) { // expected-warning {{Method call on a 'moved-from' object 'a'}} expected-note {{Method call on a 'moved-from' object 'a'}} // expected-note@-1 {{'a' became 'moved-from' here}} expected-note@-1 {{Assuming the condition is false}} expected-note@-1 {{Left side of '||' is false}} A().bar(); } } } // A range-based for sequences the loop variable declaration before the body. void forRangeSequencesTest() { A v[2] = {A(), A()}; for (A &a : v) { A b; b = std::move(a); // no-warning } } // If a variable is declared in an if statement, the declaration of the variable // (which is treated like a reinitialization by the check) is sequenced before // the evaluation of the condition (which constitutes a use). void ifStmtSequencesDeclAndConditionTest() { for (int i = 0; i < 3; ++i) { if (A a = A()) { A b; b = std::move(a); // no-warning } } } void subRegionMoveTest() { { A a; B b = std::move(a.b); // expected-note {{'b' became 'moved-from' here}} a.b.foo(); // expected-warning {{Method call on a 'moved-from' object 'b'}} expected-note {{Method call on a 'moved-from' object 'b'}} } { A a; A a1 = std::move(a); // expected-note {{Calling move constructor for 'A'}} expected-note {{Returning from move constructor for 'A'}} a.b.foo(); // expected-warning {{Method call on a 'moved-from' object 'b'}} expected-note {{Method call on a 'moved-from' object 'b'}} } // Don't report a misuse if any SuperRegion is already reported. { A a; A a1 = std::move(a); // expected-note {{'a' became 'moved-from' here}} a.foo(); // expected-warning {{Method call on a 'moved-from' object 'a'}} expected-note {{Method call on a 'moved-from' object 'a'}} a.b.foo(); // no-warning } }