// RUN: %check_clang_tidy %s cppcoreguidelines-owning-memory %t
namespace gsl {
template <class T>
using owner = T;
} // namespace gsl
template <typename T>
class unique_ptr {
public:
unique_ptr(gsl::owner<T> resource) : memory(resource) {}
unique_ptr(const unique_ptr<T> &) = default;
~unique_ptr() { delete memory; }
private:
gsl::owner<T> memory;
};
void takes_owner(gsl::owner<int *> owned_int) {
}
void takes_pointer(int *unowned_int) {
}
void takes_owner_and_more(int some_int, gsl::owner<int *> owned_int, float f) {
}
template <typename T>
void takes_templated_owner(gsl::owner<T> owned_T) {
}
gsl::owner<int *> returns_owner1() { return gsl::owner<int *>(new int(42)); } // Ok
gsl::owner<int *> returns_owner2() { return new int(42); } // Ok
int *returns_no_owner1() { return nullptr; }
int *returns_no_owner2() {
return new int(42);
// CHECK-NOTES: [[@LINE-1]]:3: warning: returning a newly created resource of type 'int *' or 'gsl::owner<>' from a function whose return type is not 'gsl::owner<>'
}
int *returns_no_owner3() {
int *should_be_owner = new int(42);
// CHECK-NOTES: [[@LINE-1]]:3: warning: initializing non-owner 'int *' with a newly created 'gsl::owner<>'
return should_be_owner;
}
int *returns_no_owner4() {
gsl::owner<int *> owner = new int(42);
return owner;
// CHECK-NOTES: [[@LINE-1]]:3: warning: returning a newly created resource of type 'int *' or 'gsl::owner<>' from a function whose return type is not 'gsl::owner<>'
}
unique_ptr<int *> returns_no_owner5() {
return unique_ptr<int *>(new int(42)); // Ok
}
/// FIXME: CSA finds it, but the report is misleading. Ownersemantics can catch this
/// by flow analysis similar to bugprone-use-after-move.
void csa_not_finding_leak() {
gsl::owner<int *> o1 = new int(42); // Ok
gsl::owner<int *> o2 = o1; // Ok
o2 = new int(45); // conceptual leak, the memory from o1 is now leaked, since its considered moved in the guidelines
delete o2;
// actual leak occurs here, its found, but mixed
delete o1;
}
void test_assignment_and_initialization() {
int stack_int1 = 15;
int stack_int2;
gsl::owner<int *> owned_int1 = &stack_int1; // BAD
// CHECK-NOTES: [[@LINE-1]]:3: warning: expected initialization with value of type 'gsl::owner<>'; got 'int *'
gsl::owner<int *> owned_int2;
owned_int2 = &stack_int2; // BAD since no owner, bad since uninitialized
// CHECK-NOTES: [[@LINE-1]]:3: warning: expected assignment source to be of type 'gsl::owner<>'; got 'int *'
gsl::owner<int *> owned_int3 = new int(42); // Good
owned_int3 = nullptr; // Good
gsl::owner<int *> owned_int4(nullptr); // Ok
owned_int4 = new int(42); // Good
gsl::owner<int *> owned_int5 = owned_int3; // Good
gsl::owner<int *> owned_int6{nullptr}; // Ok
owned_int6 = owned_int4; // Good
// FIXME:, flow analysis for the case of reassignment. Value must be released before
owned_int6 = owned_int3; // BAD, because reassignment without resource release
auto owned_int7 = returns_owner1(); // Ok, since type deduction does not eliminate the owner wrapper
const auto owned_int8 = returns_owner2(); // Ok, since type deduction does not eliminate the owner wrapper
gsl::owner<int *> owned_int9 = returns_owner1(); // Ok
int *unowned_int3 = returns_owner1(); // Bad
// CHECK-NOTES: [[@LINE-1]]:3: warning: initializing non-owner 'int *' with a newly created 'gsl::owner<>'
gsl::owner<int *> owned_int10;
owned_int10 = returns_owner1(); // Ok
int *unowned_int4;
unowned_int4 = returns_owner1(); // Bad
// CHECK-NOTES: [[@LINE-1]]:3: warning: assigning newly created 'gsl::owner<>' to non-owner 'int *'
gsl::owner<int *> owned_int11 = returns_no_owner1(); // Bad since no owner
// CHECK-NOTES: [[@LINE-1]]:3: warning: expected initialization with value of type 'gsl::owner<>'; got 'int *'
gsl::owner<int *> owned_int12;
owned_int12 = returns_no_owner1(); // Bad since no owner
// CHECK-NOTES: [[@LINE-1]]:3: warning: expected assignment source to be of type 'gsl::owner<>'; got 'int *'
int *unowned_int5 = returns_no_owner1(); // Ok
int *unowned_int6;
unowned_int6 = returns_no_owner1(); // Ok
int *unowned_int7 = new int(42); // Bad, since resource not assigned to an owner
// CHECK-NOTES: [[@LINE-1]]:3: warning: initializing non-owner 'int *' with a newly created 'gsl::owner<>'
int *unowned_int8;
unowned_int8 = new int(42);
// CHECK-NOTES: [[@LINE-1]]:3: warning: assigning newly created 'gsl::owner<>' to non-owner 'int *'
gsl::owner<int *> owned_int13 = nullptr; // Ok
}
void test_deletion() {
gsl::owner<int *> owned_int1 = new int(42);
delete owned_int1; // Good
gsl::owner<int *> owned_int2 = new int[42];
delete[] owned_int2; // Good
int *unowned_int1 = new int(42); // BAD, since new creates and owner
// CHECK-NOTES: [[@LINE-1]]:3: warning: initializing non-owner 'int *' with a newly created 'gsl::owner<>'
delete unowned_int1; // BAD, since no owner
// CHECK-NOTES: [[@LINE-1]]:3: warning: deleting a pointer through a type that is not marked 'gsl::owner<>'; consider using a smart pointer instead
// CHECK-NOTES: [[@LINE-4]]:3: note: variable declared here
int *unowned_int2 = new int[42]; // BAD, since new creates and owner
// CHECK-NOTES: [[@LINE-1]]:3: warning: initializing non-owner 'int *' with a newly created 'gsl::owner<>'
delete[] unowned_int2; // BAD since no owner
// CHECK-NOTES: [[@LINE-1]]:3: warning: deleting a pointer through a type that is not marked 'gsl::owner<>'; consider using a smart pointer instead
// CHECK-NOTES: [[@LINE-4]]:3: note: variable declared here
delete new int(42); // Technically ok, but stupid
delete[] new int[42]; // Technically ok, but stupid
}
void test_owner_function_calls() {
int stack_int = 42;
int *unowned_int1 = &stack_int;
takes_owner(&stack_int); // BAD
// CHECK-NOTES: [[@LINE-1]]:15: warning: expected argument of type 'gsl::owner<>'; got 'int *'
takes_owner(unowned_int1); // BAD
// CHECK-NOTES: [[@LINE-1]]:15: warning: expected argument of type 'gsl::owner<>'; got 'int *'
gsl::owner<int *> owned_int1 = new int(42);
takes_owner(owned_int1); // Ok
takes_owner_and_more(42, &stack_int, 42.0f); // BAD
// CHECK-NOTES: [[@LINE-1]]:28: warning: expected argument of type 'gsl::owner<>'; got 'int *'
takes_owner_and_more(42, unowned_int1, 42.0f); // BAD
// CHECK-NOTES: [[@LINE-1]]:28: warning: expected argument of type 'gsl::owner<>'; got 'int *'
takes_owner_and_more(42, new int(42), 42.0f); // Ok, since new is consumed by owner
takes_owner_and_more(42, owned_int1, 42.0f); // Ok, since owner as argument
takes_templated_owner(owned_int1); // Ok
takes_templated_owner(new int(42)); // Ok
takes_templated_owner(unowned_int1); // Bad
// CHECK-NOTES: [[@LINE-1]]:25: warning: expected argument of type 'gsl::owner<>'; got 'int *'
takes_owner(returns_owner1()); // Ok
takes_owner(returns_no_owner1()); // BAD
// CHECK-NOTES: [[@LINE-1]]:15: warning: expected argument of type 'gsl::owner<>'; got 'int *'
}
void test_unowned_function_calls() {
int stack_int = 42;
int *unowned_int1 = &stack_int;
gsl::owner<int *> owned_int1 = new int(42);
takes_pointer(&stack_int); // Ok
takes_pointer(unowned_int1); // Ok
takes_pointer(owned_int1); // Ok
takes_pointer(new int(42)); // Bad, since new creates and owner
// CHECK-NOTES: [[@LINE-1]]:17: warning: initializing non-owner argument of type 'int *' with a newly created 'gsl::owner<>'
takes_pointer(returns_owner1()); // Bad
// CHECK-NOTES: [[@LINE-1]]:17: warning: initializing non-owner argument of type 'int *' with a newly created 'gsl::owner<>'
takes_pointer(returns_no_owner1()); // Ok
}
// FIXME: Typedefing owner<> to something else does not work.
// This might be necessary for code already having a similar typedef like owner<> and
// replacing it with owner<>. This might be the same problem as with templates.
// The canonical type will ignore the owner<> alias, since its a typedef as well.
//
// Check, if owners hidden by typedef are handled the same as 'obvious' owners.
#if 0
using heap_int = gsl::owner<int *>;
typedef gsl::owner<float *> heap_float;
// This tests only a subset, assuming that the check will either see through the
// typedef or not (it doesn't!).
void test_typedefed_values() {
// Modern typedef.
int StackInt1 = 42;
heap_int HeapInt1 = &StackInt1;
// CHECK MESSAGES: [[@LINE-1]]:3: warning: expected assignment source to be of type 'gsl::owner<>'; got 'int *'
//FIXME: Typedef not considered correctly here.
// heap_int HeapInt2 = new int(42); // Ok
takes_pointer(HeapInt1); // Ok
takes_owner(HeapInt1); // Ok
// Traditional typedef.
float StackFloat1 = 42.0f;
heap_float HeapFloat1 = &StackFloat1;
// CHECK MESSAGES: [[@LINE-1]]:3: warning: expected assignment source to be of type 'gsl::owner<>'; got 'float *'
//FIXME: Typedef not considered correctly here.
// heap_float HeapFloat2 = new float(42.0f);
HeapFloat2 = HeapFloat1; // Ok
}
#endif
struct ArbitraryClass {};
struct ClassWithOwner { // Does not define destructor, necessary with owner
ClassWithOwner() : owner_var(nullptr) {} // Ok
ClassWithOwner(ArbitraryClass &other) : owner_var(&other) {}
// CHECK-NOTES: [[@LINE-1]]:43: warning: expected initialization of owner member variable with value of type 'gsl::owner<>'; got 'ArbitraryClass *'
ClassWithOwner(gsl::owner<ArbitraryClass *> other) : owner_var(other) {} // Ok
ClassWithOwner(gsl::owner<ArbitraryClass *> data, int /* unused */) { // Ok
owner_var = data; // Ok
}
ClassWithOwner(ArbitraryClass *bad_data, int /* unused */, int /* unused */) {
owner_var = bad_data;
// CHECK-NOTES: [[@LINE-1]]:5: warning: expected assignment source to be of type 'gsl::owner<>'; got 'ArbitraryClass *'
}
ClassWithOwner(ClassWithOwner &&other) : owner_var{other.owner_var} {} // Ok
ClassWithOwner &operator=(ClassWithOwner &&other) {
owner_var = other.owner_var; // Ok
return *this;
}
// Returning means, that the owner is "moved", so the class should not access this
// variable anymore after this method gets called.
gsl::owner<ArbitraryClass *> buggy_but_returns_owner() { return owner_var; }
gsl::owner<ArbitraryClass *> owner_var;
// CHECK-NOTES: [[@LINE-1]]:3: warning: member variable of type 'gsl::owner<>' requires the class 'ClassWithOwner' to implement a destructor to release the owned resource
};
class DefaultedDestructor { // Bad since default constructor with owner
~DefaultedDestructor() = default; // Bad, since will not destroy the owner
gsl::owner<int *> Owner;
// CHECK-NOTES: [[@LINE-1]]:3: warning: member variable of type 'gsl::owner<>' requires the class 'DefaultedDestructor' to implement a destructor to release the owned resource
};
struct DeletedDestructor {
~DeletedDestructor() = delete;
gsl::owner<int *> Owner;
// CHECK-NOTES: [[@LINE-1]]:3: warning: member variable of type 'gsl::owner<>' requires the class 'DeletedDestructor' to implement a destructor to release the owned resource
};
void test_class_with_owner() {
ArbitraryClass A;
ClassWithOwner C1; // Ok
ClassWithOwner C2{A}; // Bad, since the owner would be initialized with an non-owner, but catched in the class
ClassWithOwner C3{gsl::owner<ArbitraryClass *>(new ArbitraryClass)}; // Ok
const auto Owner1 = C3.buggy_but_returns_owner(); // Ok, deduces Owner1 to owner<ArbitraryClass *> const
auto Owner2 = C2.buggy_but_returns_owner(); // Ok, deduces Owner2 to owner<ArbitraryClass *>
Owner2 = &A; // BAD, since type deduction resulted in owner<ArbitraryClass *>
// CHECK-NOTES: [[@LINE-1]]:3: warning: expected assignment source to be of type 'gsl::owner<>'; got 'ArbitraryClass *'
gsl::owner<ArbitraryClass *> Owner3 = C1.buggy_but_returns_owner(); // Ok, still an owner
Owner3 = &A; // Bad, since assignment of non-owner to owner
// CHECK-NOTES: [[@LINE-1]]:3: warning: expected assignment source to be of type 'gsl::owner<>'; got 'ArbitraryClass *'
}
template <typename T>
struct HeapArray { // Ok, since destructor with owner
HeapArray() : _data(nullptr), size(0) {} // Ok
HeapArray(int size) : _data(new int[size]), size(size) {} // Ok
HeapArray(int size, T val) {
_data = new int[size]; // Ok
size = size;
for (auto i = 0u; i < size; ++i)
_data[i] = val; // Ok
}
HeapArray(int size, T val, int *problematic) : _data{problematic}, size(size) {} // Bad
// CHECK-NOTES: [[@LINE-1]]:50: warning: expected initialization of owner member variable with value of type 'gsl::owner<>'; got 'void'
// FIXME: void is incorrect type, probably wrong thing matched
HeapArray(HeapArray &&other) : _data(other._data), size(other.size) { // Ok
other._data = nullptr; // Ok
// CHECK-NOTES: [[@LINE-1]]:5: warning: expected assignment source to be of type 'gsl::owner<>'; got 'std::nullptr_t'
// FIXME: This warning is emitted because an ImplicitCastExpr for the NullToPointer conversion isn't created for dependent types.
other.size = 0;
}
HeapArray<T> &operator=(HeapArray<T> &&other) {
_data = other._data; // Ok, NOLINT warning here about bad types, why?
size = other.size;
return *this;
}
~HeapArray() { delete[] _data; } // Ok
T *data() { return _data; } // Ok NOLINT, because it "looks" like a factory
gsl::owner<T *> _data;
unsigned int size;
};
void test_inner_template() {
HeapArray<int> Array1;
HeapArray<int> Array2(100);
HeapArray<int> Array3(100, 0);
HeapArray<int> Array4(100, 0, nullptr);
Array1 = static_cast<HeapArray<int> &&>(Array2);
HeapArray<int> Array5(static_cast<HeapArray<int> &&>(Array3));
int *NonOwningPtr = Array1.data(); // Ok
gsl::owner<int *> OwningPtr = Array1.data(); // Bad, since it does not return the owner
// CHECK-NOTES: [[@LINE-1]]:3: warning: expected initialization with value of type 'gsl::owner<>'; got 'int *'
}
// FIXME: Typededuction removes the owner - wrapper, therefore gsl::owner can not be used
// with Template classes like this. Is there a walkaround?
template <typename T>
struct TemplateValue {
TemplateValue() = default;
TemplateValue(T t) : val{t} {}
void setVal(const T &t) { val = t; }
const T getVal() const { return val; }
T val;
};
// FIXME: Same typededcution problems
template <typename T>
void template_function(T t) {
gsl::owner<int *> owner_t = t; // Probably bad, since type deduction still wrong
// CHECK-NOTES: [[@LINE-1]]:3: warning: expected initialization with value of type 'gsl::owner<>'; got 'T'
// CHECK-NOTES: [[@LINE-2]]:3: warning: expected initialization with value of type 'gsl::owner<>'; got 'int *'
}
// FIXME: Same typededcution problems
void test_templates() {
int stack_int = 42;
int *stack_ptr1 = &stack_int;
TemplateValue<gsl::owner<int *>> Owner0; // Ok, T should be owner, but is int*
TemplateValue<gsl::owner<int *>> Owner1(new int(42)); // Ok, T should be owner, but is int*
Owner1.setVal(&stack_int); // Bad since non-owner assignment
Owner1.setVal(stack_ptr1); // Bad since non-owner assignment
//Owner1.setVal(new int(42)); // Ok, but since type deduction is wrong, this one is considered harmful
int *stack_ptr2 = Owner1.getVal(); // Bad, initializing non-owner with owner
TemplateValue<int *> NonOwner1(new int(42)); // Bad, T is int *, hence dynamic memory to non-owner
gsl::owner<int *> IntOwner1 = NonOwner1.getVal(); // Bad, since owner initialized with non-owner
// CHECK-NOTES: [[@LINE-1]]:3: warning: expected initialization with value of type 'gsl::owner<>'; got 'int *'
template_function(IntOwner1); // Ok, but not actually ok, since type deduction removes owner
template_function(stack_ptr1); // Bad, but type deduction gets it wrong
}
namespace PR63994 {
struct A {
virtual ~A() {}
};
struct B : public A {};
A* foo(int x) {
return new B;
// CHECK-NOTES: [[@LINE-1]]:5: warning: returning a newly created resource of type 'A *' or 'gsl::owner<>' from a function whose return type is not 'gsl::owner<>'
}
}
namespace PR59389 {
struct S {
S();
S(int);
int value = 1;
};
void testLambdaInFunctionNegative() {
const auto MakeS = []() -> ::gsl::owner<S*> {
return ::gsl::owner<S*>{new S{}};
};
}
void testLambdaInFunctionPositive() {
const auto MakeS = []() -> S* {
return ::gsl::owner<S*>{new S{}};
// CHECK-NOTES: [[@LINE-1]]:7: warning: returning a newly created resource of type 'S *' or 'gsl::owner<>' from a lambda whose return type is not 'gsl::owner<>'
};
}
void testFunctionInFunctionNegative() {
struct C {
::gsl::owner<S*> test() {
return ::gsl::owner<S*>{new S{}};
}
};
}
void testFunctionInFunctionPositive() {
struct C {
S* test() {
return ::gsl::owner<S*>{new S{}};
// CHECK-NOTES: [[@LINE-1]]:9: warning: returning a newly created resource of type 'S *' or 'gsl::owner<>' from a function whose return type is not 'gsl::owner<>'
}
};
}
::gsl::owner<S*> testReverseLambdaNegative() {
const auto MakeI = [] -> int { return 5; };
return ::gsl::owner<S*>{new S(MakeI())};
}
S* testReverseLambdaPositive() {
const auto MakeI = [] -> int { return 5; };
return ::gsl::owner<S*>{new S(MakeI())};
// CHECK-NOTES: [[@LINE-1]]:5: warning: returning a newly created resource of type 'S *' or 'gsl::owner<>' from a function whose return type is not 'gsl::owner<>'
}
::gsl::owner<S*> testReverseFunctionNegative() {
struct C {
int test() { return 5; }
};
return ::gsl::owner<S*>{new S(C().test())};
}
S* testReverseFunctionPositive() {
struct C {
int test() { return 5; }
};
return ::gsl::owner<S*>{new S(C().test())};
// CHECK-NOTES: [[@LINE-1]]:5: warning: returning a newly created resource of type 'S *' or 'gsl::owner<>' from a function whose return type is not 'gsl::owner<>'
}
void testLambdaInLambdaNegative() {
const auto MakeS = []() -> ::gsl::owner<S*> {
const auto MakeI = []() -> int { return 5; };
return ::gsl::owner<S*>{new S(MakeI())};
};
}
void testLambdaInLambdaPositive() {
const auto MakeS = []() -> S* {
const auto MakeI = []() -> int { return 5; };
return ::gsl::owner<S*>{new S(MakeI())};
// CHECK-NOTES: [[@LINE-1]]:7: warning: returning a newly created resource of type 'S *' or 'gsl::owner<>' from a lambda whose return type is not 'gsl::owner<>'
};
}
void testLambdaInLambdaWithDoubleReturns() {
const auto MakeS = []() -> S* {
const auto MakeS2 = []() -> S* {
return ::gsl::owner<S*>{new S(1)};
// CHECK-NOTES: [[@LINE-1]]:9: warning: returning a newly created resource of type 'S *' or 'gsl::owner<>' from a lambda whose return type is not 'gsl::owner<>' [cppcoreguidelines-owning-memory]
};
return ::gsl::owner<S*>{new S(2)};
// CHECK-NOTES: [[@LINE-1]]:7: warning: returning a newly created resource of type 'S *' or 'gsl::owner<>' from a lambda whose return type is not 'gsl::owner<>'
};
}
void testReverseLambdaInLambdaNegative() {
const auto MakeI = []() -> int {
const auto MakeS = []() -> ::gsl::owner<S*> { return new S(); };
return 5;
};
}
void testReverseLambdaInLambdaPositive() {
const auto MakeI = []() -> int {
const auto MakeS = []() -> S* { return new S(); };
// CHECK-NOTES: [[@LINE-1]]:39: warning: returning a newly created resource of type 'S *' or 'gsl::owner<>' from a lambda whose return type is not 'gsl::owner<>'
return 5;
};
}
}
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