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I was using the following to get a memory address for functions pointers to prevent ambiguity, but unsure if this correct
but this also works, but displays a different value, and not sure which is correctCode:void(*f)(void);
std::cout << "Address: " << &(*f) << '\n';
Thank you for your assistance.Code:void(*f)(void);
std::cout << "Address: " << &(&(*f)) << '\n';
//Just thought about it, but this one is also the same as &(f) I think
& and * always eat each other; so the first is f (i.e., the value of f, the pointer it contains), while the second is &f (the memory address where the variable f is stored).
well, that is something i didn't know. Thank you tabstop.
I suppose I should be more specific, since this is C++: & and * will always eat each other, unless you've overloaded one of the operators.
Also, the second is invalid, and it's a quirk of GCC that it is accepted anyway.
Actually I think the first one is invalid, because you're casting a function pointer to a void pointer, which is not allowed, because some architectures make data pointers and function pointer incompatible entities, and C is written to allow for such architectures. The second one looks fine: you're casting a function pointer pointer, which is a data pointer, to void *.
There is no cast in the first. However, you'll only get "1" as an output, since the implicit conversion done for output is to bool.
The second is invalid because address-of anything is an rvalue, and you can't take the address of an rvalue.
I meant implicit cast. But if you're saying that it converts to bool that makes sense. Yet the OP seemed to imply that he was getting something that looked like a memory address. Compiler bug?Quote:
Originally Posted by CornedBee
Oh, right.Quote:
The second is invalid because address-of anything is an rvalue, and you can't take the address of an rvalue.
Good question. GCC 4.1 gives me "1". But then, GCC 4.1 also refuses the compile the second version.Quote:
Yet the OP seemed to imply that he was getting something that looked like a memory address. Compiler bug?
OP: What compiler do you use?