c++ - Can a preexisting return of a typecast NULL be safely compared to a newer nullptr? -

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i required use library written before c++11, , 1 of functions can return typecast null. i'm trying write program following c++11 standards, when protecting against null reference, use like:

if(retptr==nullptr){...}

is safe comparison? arguments sake between (int*)null , (int*)nullptr? or should use an:

if(retptr){...}?

can preexisting return of typecast null safely compared newer nullptr?

yes. cppreference.com:

there exist implicit conversions nullptr null pointer value of pointer type , pointer member type. similar conversions exist value of type std::nullptr_t macro null, null pointer constant.

as praetorian kindly pointed out, corresponding section of standard 4.10 [conv.ptr].

see what nullptr?


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