Thread: enum

Enum's are basically just ints:

Code:

enum data {one,two,three};
data test;
cout << sizeof(test);

Outputs "4" (4 bytes, 32 bits) on my machine.

They might not be, though. The standard only requires them to be large enough to hold all values. The data enum, the highest value being 2, might be anything from 1 to 8 bytes long. All DirectX enums have for that reason a member called FORCE_DWORD (or some variant) that has the value 0xffffffff and forces 4 bytes size.

bool isn't 1 bit large btw, it's usually 1, 2 or 4 bytes large.

Originally posted by CornedBee
They might not be, though. The standard only requires them to be large enough to hold all values. The data enum, the highest value being 2, might be anything from 1 to 8 bytes long.

According to my copy of the standard (C89):

Each enumerated type shall be compatible with an integer type: the choice of type is implementation-defined."

IOW, the compiler may define a special type for an enum, but will ultimately be an int or int look-alike.

I'm not certain if the C-99 or C++ standard has redefined this or not, but I doubt it.

char and short are integer types too.