Unknown error in array initilization

Question

I was trying to make a Intel 8080 CPU emulator (then I'd like to emulate Space Invaders, which use it).

I coded nearly complete implementation of this CPU (thanks to MAME and Tickle project (mostly) ;) ) except undocument instructions (0x08, 0x10, 0x18, 0x20, 0x28, 0x30, 0x38, 0x0CB, 0x0D9, 0x0DD, 0x0ED, 0x0FD).

I've have only problems when I compile it, I don't know why.

This is the code:

static const unsigned char cycles_table[256] =
{
    /*                       8080's Cycles Table                         */
    /*     0   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F */
    /*0*/  4, 10,  7,  5,  5,  5,  7,  4,  0, 10,  7,  5,  5,  5,  7,  4,
    /*1*/  0, 10,  7,  5,  5,  5,  7,  4,  0, 10,  7,  5,  5,  5,  7,  4,
    /*2*/  0, 10, 16,  5,  5,  5,  7,  4,  0, 10, 16,  5,  5,  5,  7,  4,
    /*3*/  0, 10, 13,  5, 10, 10, 10,  4,  0, 10, 13,  5,  5,  5,  7,  4,
    /*4*/  5,  5,  5,  5,  5,  5,  7,  5,  5,  5,  5,  5,  5,  5,  7,  5,
    /*5*/  5,  5,  5,  5,  5,  5,  7,  5,  5,  5,  5,  5,  5,  5,  7,  5,
    /*6*/  5,  5,  5,  5,  5,  5,  7,  5,  5,  5,  5,  5,  5,  5,  7,  5,
    /*7*/  7,  7,  7,  7,  7,  7,  7,  7,  5,  5,  5,  5,  5,  5,  7,  5,
    /*8*/  4,  4,  4,  4,  4,  4,  7,  4,  4,  4,  4,  4,  4,  4,  7,  4,
    /*9*/  4,  4,  4,  4,  4,  4,  7,  4,  4,  4,  4,  4,  4,  4,  7,  4,
    /*A*/  4,  4,  4,  4,  4,  4,  7,  4,  4,  4,  4,  4,  4,  4,  7,  4,
    /*B*/  4,  4,  4,  4,  4,  4,  7,  4,  4,  4,  4,  4,  4,  4,  7,  4,
    /*C*/  5, 10, 10, 10, 11, 11,  7, 11,  5, 10, 10,  0, 11, 17,  7, 11,
    /*D*/  5, 10, 10, 10, 11, 11,  7, 11,  5,  0, 10, 10, 11,  0,  7, 11,
    /*E*/  5, 10, 10, 18, 11, 11,  7, 11,  5,  5, 10,  4, 11,  0,  7, 11,
    /*F*/  5, 10, 10,  4, 11, 11,  7, 11,  5,  5, 10,  4, 11,  0,  7, 11
};

g++ takes me this error:

8080.h:521: error: invalid in-class initialization of static data member of non- integral type `const unsigned char[256]'

This array is in a class called i8080.

Answer 1

Like it says, you cannot initialize static non-integral types in a class definition. That is, you could do this:

static const unsigned value = 123;
static const bool value_again = true;

But not anything else.

What you should do is place this in your class definition:

static const unsigned char cycles_table[256];

And in the corresponding source file, place what you have:

const unsigned char i8080::cycles_table[256] = // ...

What this does is say (in the definition), "Hey, there's gonna be this array." and in the source file, "Hey, here's that array."

Answer 2

Static data members need to be initialised outside of the class.

Answer 3

You cannot initialize a static array embedded within a class like this:

class Thing
{
public:
    static const int [3] = {1, 2, 3};
};

You have to do it like this:

thing.h:

class Thing
{
public:
    static const int vals[3];;
};

thing.cpp:

const int Thing::vals[3] = {1, 2, 3};