Why am I getting this error: "data definition has no type or storage class"?

c pointers struct bison cc
Daivid picture Daivid · Sep 20, 2013 · Viewed 33.9k times · Source 
#include <stdio.h>
#include <stdlib.h>

struct NODE {
    char* name;
    int val;
    struct NODE* next;
};
typedef struct NODE Node;

Node *head, *tail;
head = (Node*) malloc( sizeof( Node ) ); //line 21

And I compiling like this:

cc -g -c -o file.tab.o file.tab.c

I'm getting this error message:

file.y:21:1 warning: data definition has no type or storage class [enabled by default]

Answer

Natan Streppel picture Natan Streppel · Sep 20, 2013

It looks like the line

head = (Node*) malloc( sizeof( Node ) ); //line 21

is outside the main() function. You can't do that, because you can't execute code outside functions. The only thing you can do at global scope is declaring variables. Just move it inside the main() or any other function, and the problem should go away.

(PS: Take a look at this question on why you shouldn't type-cast malloc)

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