False positive passedByValue for function pointer with using-declaration

[ptomato]

bug.cpp:

#include <vector>
struct S {
    std::vector<int> v;
    using F = void (*)();
    void func(F f);
};
void S::func(S::F f) {}

Output:

 cppcheck bug.cpp --enable=performance
Checking bug.cpp ...
bug.cpp:7:19: performance: Function parameter 'f' should be passed by const reference. [passedByValue]
void S::func(S::F f) {}
                  ^

F should not be marked as being passed by value, because it is a pointer.

Any of the following changes will make this error disappear:

• Remove the v member or replace it by a member with a POD type such as int. (But std::deque<int> v still shows the error, for example)
• Write out the function pointer type instead of a using-declaration.
• Move the body of func inline in the class declaration.
• Change the type alias F to a data pointer, such as void*.

Observed with cppcheck 2.6.

[chrchr]

There's also no warning with typedef void (*F)();.

[chrchr]

Related: #10252

[chrchr]

Variable f doesn't have the pointer flag.

[kidkat]

This started with 2.4 and has been bisected to ​https://github.com/danmar/cppcheck/commit/3c6fae37e439c2b264d1712e5a6d45c6878be276.

It was also previously reported from 1.75 to 1.90.