5 replies to this topic

[Aereshaa]

So, I'm at the moment working on an emulator for the Nintendo Entertainment System, aka the Famicom. This entails writing a simulation of the MOS 6502 processor. However, a error has come up on a very simple function declaration, and I'm flummoxed as to the reason.
When taken alone, the declaration:

//#define PREPROCESSOR_TYPES
#ifdef PREPROCESSOR_TYPES
#define byte unsigned char
#define word unsigned short
#else
typedef unsigned char byte;
typedef unsigned short word;
#endif
word rdwd6502(word addr);

--returns no errors. but, when in its actual context in the program (files attached), it returns the following compiler error:

6502.c:3: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘rdwd6502’
6502.c:43: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘rdwd6502’

So, can anyone explain this phantom to me, or is it something very simple that I've missed?
EDIT: SOLVED.

Attached Files

•  attach.zip   1.62K   9 downloads

Edited by Aereshaa, 26 August 2009 - 01:48 PM.

[WingedPanther]

What happens with this code:

typedef unsigned char byte;
typedef unsigned short word;
word rdwd6502(word addr);

or this:

unsigned short rdwd6502(unsigned short addr);

[Aereshaa]

Both return no errors when on their own, but the first one returns an error when in context, whereas the second one doesn't, even though they should be equivalent. Even when word is defined by a preprocessor macro, it still returns an error unless I specify unsigned short.

[WingedPanther]

what if you explicitly specify int?
"unsigned short int"?

[dcs]

Did you muff the header guard?

#ifdef PROCESSOR_6502

Usually they're written:

#if[COLOR="Red"]n[/COLOR]def PROCESSOR_6502

[Aereshaa]

Okay, dcs, that somehow solved the phantom, and revealed bugs and warnings that it was obscuring. Although I cannot imagine how it was done, thank you.