bugprone-unique-ptr-array-mismatch¶
Finds initializations of C++ unique pointers to non-array type that are initialized with an array.
If a pointer std::unique_ptr<T>
is initialized with a new-expression
new T[]
the memory is not deallocated correctly. A plain delete
is used
in this case to deallocate the target memory. Instead a delete[]
call is
needed. A std::unique_ptr<T[]>
uses the correct delete operator. The check
does not emit warning if an unique_ptr
with user-specified deleter type is
used.
The check offers replacement of unique_ptr<T>
to unique_ptr<T[]>
if it
is used at a single variable declaration (one variable in one statement).
Example:
std::unique_ptr<Foo> x(new Foo[10]); // -> std::unique_ptr<Foo[]> x(new Foo[10]);
// ^ warning: unique pointer to non-array is initialized with array
std::unique_ptr<Foo> x1(new Foo), x2(new Foo[10]); // no replacement
// ^ warning: unique pointer to non-array is initialized with array
D d;
std::unique_ptr<Foo, D> x3(new Foo[10], d); // no warning (custom deleter used)
struct S {
std::unique_ptr<Foo> x(new Foo[10]); // no replacement in this case
// ^ warning: unique pointer to non-array is initialized with array
};
This check partially covers the CERT C++ Coding Standard rule
MEM51-CPP. Properly deallocate dynamically allocated resources
However, only the std::unique_ptr
case is detected by this check.