Thread: C structure basic code not compiling

hello sirs, why is this code not working? it does nothing special just trying to understand.

Code:

#include <stdio.h>
#include <stdlib.h>

struct node

{
    int a;
    struct node *next;

};
struct node *a;
a = (struct node *)malloc(sizeof(struct node));
int main(){

//d nothing

}

the error on the compiler logs(code blocks)

are

Code:

||=== Build file: "no target" in "no project" (compiler: unknown) ===|
C:\Users\xx\Documents\strcts\struct_stack.c|12|warning: data definition has no type or storage class|
C:\Users\xx\Documents\strcts\struct_stack.c|12|error: conflicting types for 'a'|
C:\Users\xx\Documents\strcts\struct_stack.c|11|note: previous declaration of 'a' was here|
C:\Users\xx\Documents\strcts\struct_stack.c|12|warning: initialization makes integer from pointer without a cast|
C:\Users\xx\Documents\strcts\struct_stack.c|12|error: initializer element is not constant|
||=== Build failed: 2 error(s), 2 warning(s) (0 minute(s), 0 second(s)) ===|