Conflicting types error and invalid type argument of unary * have int

Question

I have very simple program here, I get errors like :

conflicting type of 'f' 

previous declaration of 'f' was here

error : initializer element is not computable at load time 

in function queue_ready: 

invalid type argument of unary '*' (have'int') 

in function dequeue_ready : 

invalid type argument of unary '*' (have'int') 

Where are my mistakes?

#include<stdio.h> 

int Queue_ready[1000]; 
int *r ;
int *f ; 
r=&Queue_ready[0];
f=&Queue_ready[0];

void queue_ready (int process) 
{
   *r=process; 
    r = r+1;
} 

void dequeue_ready (void) 
{
   *f = 10000; 
   f=f+1;
}

int main() 
{
   queue_ready(1); 
   queue_ready(2);
   printf("%d %d" , Queue_ready[0] ,Queue_ready[1]); 
   dequeue_ready();
   dequeue_ready();
   return 0;  
} 

Answer 1

The problem is here:

int *r;
int *f; 
r=&Queue_ready[0];
f=&Queue_ready[0];

These lines lie outside of a function. The first two are OK, since they declare variables, but the next two are not since they are statements , and statements are not allowed outside of a function.

The reason you're getting a "conflicting type" error is because the statement (that the compiler isn't expecting) is being read as a declaration . Since this "declaration" doesn't specify a type, it has an implied type of int which conflicts with the prior definition of type int * .

Because what you actually want to do is initialize these variables (as opposed to assign), you do so at the time they are declared:

int *r = &Queue_ready[0];
int *f = &Queue_ready[0];