#define statements on variable declarations

Hello. I am trying to find new and exciting ways to optimize (read: shrink down) my current code and want to include an eeprom autorefresh option to cut down on variables. Basically, when I have the AutoRefreshCompile option set, I want it to create the variable "randomvariable". My code is pretty simple:

#define AutoRefreshCompile 1

        #if(AutoRefreshCompile==1)
        {  // line x
                extern signed short randomvariable;
        }  // line y
        #endif

I am getting errors that read as follows:

VARS.H(x) error C141: syntax error near '{'
VARS.H(y) error C141: syntax error near '}'

I'm guessing it is not possible to do this (if I remember correctly, variables have to be declared at the beginning and can't be in the middle of functions/code segments but maybe it's some really simple fix.

I realize this might not work but I figure it's worth a shot. Any suggestions? Thanks!