Thread: Noobie C question, quick answer

Hello, I am writing a C compiler in Java and I'm getting the following errors in one of my generated C programs:


output.c:6: warning: data definition has no type or storage class
output.c:6: error: conflicting types for ‘M’
output.c:1: note: previous declaration of ‘M’ was here
output.c:6: error: invalid initializer
output.c:7: warning: data definition has no type or storage class
output.c:7: error: conflicting types for ‘M’
output.c:1: note: previous declaration of ‘M’ was here
output.c:7: error: invalid initializer

and my program looks like:

Code:

int M[5000];
#define base M[0]
#define top M[1]
#define jump_reg M[2]

base = 3;
top = 3;
 #include <stdio.h>
int max ( int a , int b ) 
{
	if ( a > b ) goto AutoGenLabel1;//auto-if
	goto AutoGenLabel0;//auto-if
	AutoGenLabel1://auto-if
	return a;
	AutoGenLabel0://auto-if
	;//auto-if
	return b;
}
int main ( ) 
{
	int a , b;
	scanf ( "%d" , & a );
	scanf ( "%d" , & b );
	M[base] = max ( a , b );//auto
	printf ( "%d\n" , M[base] );
}

What exactly is going on?

Thanks for your fast respone

You can define constants and variables globally (i.e. outside of any function), but statements, including assignments, can only be executed inside a function. Put your assignments

Code:

base = 3;
top = 3;

inside the main function.

You can't declare variables outside of a function. You can define them, but you can't give them a value.

Of course C will let you put those statments outside of main. But you need to specify their type as int base = 3; or float top = 2; They will then become global variables with a preset first value (i.e. initializers)

Yikes... Elysia... did I actually make it into your Sig?

Originally Posted by Elysia

Yes, I couldn't resist quoting that, since I feel the same way!

ROFL... I don't know... should I be flattered or embarassed????

Originally Posted by CommonTater

Of course C will let you put those statments outside of main. But you need to specify their type as int base = 3; or float top = 2; They will then become global variables with a preset first value (i.e. initializers)

That is exactly what "define a variable" means. However, in this case he can't do that, because he has already #define'd base and top in the preprocessor directives at the beginning of the program, so the assignments MUST be inside a function.