Error with struct declare ( error: array type has incomplete element type 'struct entry' )-CodePudding

I have this code and I run it and get his error :

error: array type has incomplete element type 'struct entry'

and I try it to solve it and explore same error but got fail

    #ifndef GLOBAL_H
#define GLOBAL_H

#define _CRT_SECURE_NO_WARNINGS

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <getopt.h>

//list of CONSTANTS
#define BSIZE  128
#define NONE   -1
#define EOS    '\0'

#define NUM     256
#define DIV     257
#define MOD     258
#define ID      259
#define DONE    260


//list of prototype function
void init();
int lexan();
int lookup(char s[]);
int insert(char s[], int tok);
void emit(int t,int tval);
void parse();
void expr();
void term();
void factor();
void match(int t);
void error(char* m);

//list of variables
FILE *input, *output, *err;

int tokenval;

int lineno;

int lookahead;

extern struct entry symtable[];

struct entry {
    char *lexptr;
    int token;
};

#endif

and I get error in this line :

extern struct entry symtable[];

this is code for ( global.h ) and other file not get an error

CodePudding user response：

Move the struct entry definition to be placed before it is first used.

struct entry {
    char *lexptr;
    int token;
};

extern struct entry symtable[];