c++ - Misleading performance warning for auto_ptr type passed by value -

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i'm checking 1 of projects cppcheck 1.75, , code (reduced clarity):

class tjob { public:     tjob(std::auto_ptr<itask> task);     // ... private:     std::auto_ptr<itask> m_task; };  tjob::tjob(     std::auto_ptr<itask> task // <-- here performance warning     ): m_task(task) {     trace("tjob ctr"); }

i'm getting new performance warning:

id: passedbyvalue

summary: function parameter 'task' should passed reference.

message: parameter 'task' passed value. passed (const) reference faster , recommended in c++.

which false positive. in opinion it's bug, because following suggestion leads serious bug[1], maybe there switch missed set, or template can provide declare ownership passed auto_ptr?

i searched web , found far cppcheck incorporates checks check invalid usage of stl, example

- using auto pointer (auto_ptr)

i'm aware, auto_ptr isn't best choice wouldn't same unique_ptr? 2 checks interfere here?

besides using inline supression, possible suppress warnings cases?

edit: added footnote.
[1] there no serious bug, misunderstanding using std::auto_ptr. somehow mixed compile-time run-time semantics: ownership isn't passed compile-time magic, rather @ runtime invoking "copy" constructor.

it has correctly detected passing value copy constructor when pass reference , amortise 1 of copies. optimiser fix 'issue' there not real need rely on it.

i expression of interface preferable in auto_ptr's case because tells caller taking pointer, core issue auto_ptr bad citizen (can left in invalid state copy operation), why deprecated.


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