Thread: array type has incomplete element type

hello I've just been trying to get this lines of code to compile in gcc. It does in visual studio 2017 so I just don't really understand this errors

Code:

 
In file included from contacts.c:19:0:
contactHelpers.h:54:35: error: array type has incomplete element type
contactHelpers.h:54:35: warning: ‘struct Contact’ declared inside parameter list [enabled by default]
contactHelpers.h:54:35: warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default]
contactHelpers.h:63:34: warning: ‘struct Contact’ declared inside parameter list [enabled by default]
contactHelpers.h:66:35: error: array type has incomplete element type
contactHelpers.h:66:35: warning: ‘struct Contact’ declared inside parameter list [enabled by default]
contactHelpers.h:69:34: error: array type has incomplete element type
contactHelpers.h:69:34: warning: ‘struct Contact’ declared inside parameter list [enabled by default]
contactHelpers.h:72:24: error: array type has incomplete element type
contactHelpers.h:72:24: warning: ‘struct Contact’ declared inside parameter list [enabled by default]
contactHelpers.h:75:27: error: array type has incomplete element type
contactHelpers.h:75:27: warning: ‘struct Contact’ declared inside parameter list [enabled by default]
contactHelpers.h:78:27: error: array type has incomplete element type
contactHelpers.h:78:27: warning: ‘struct Contact’ declared inside parameter list [enabled by default]
In file included from contactHelpers.c:23:0:
contactHelpers.h:54:35: error: array type has incomplete element type
contactHelpers.h:54:35: warning: ‘struct Contact’ declared inside parameter list [enabled by default]
contactHelpers.h:54:35: warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default]
contactHelpers.h:63:34: warning: ‘struct Contact’ declared inside parameter list [enabled by default]
contactHelpers.h:66:35: error: array type has incomplete element type
contactHelpers.h:66:35: warning: ‘struct Contact’ declared inside parameter list [enabled by default]
contactHelpers.h:69:34: error: array type has incomplete element type
contactHelpers.h:69:34: warning: ‘struct Contact’ declared inside parameter list [enabled by default]
contactHelpers.h:72:24: error: array type has incomplete element type
contactHelpers.h:72:24: warning: ‘struct Contact’ declared inside parameter list [enabled by default]
contactHelpers.h:75:27: error: array type has incomplete element type
contactHelpers.h:75:27: warning: ‘struct Contact’ declared inside parameter list [enabled by default]
contactHelpers.h:78:27: error: array type has incomplete element type
contactHelpers.h:78:27: warning: ‘struct Contact’ declared inside parameter list [enabled by default]
contactHelpers.c: In function ‘ContactManagerSystem’:
contactHelpers.c:178:4: error: type of formal parameter 1 is incomplete
contactHelpers.c:183:4: error: type of formal parameter 1 is incomplete
contactHelpers.c:188:4: error: type of formal parameter 1 is incomplete
contactHelpers.c:193:4: error: type of formal parameter 1 is incomplete
contactHelpers.c:198:4: error: type of formal parameter 1 is incomplete
contactHelpers.c: At top level:
contactHelpers.c:269:6: error: conflicting types for ‘displayContact’
contactHelpers.h:63:6: note: previous declaration of ‘displayContact’ was here
contactHelpers.c:178: confused by earlier errors, bailing out

here are my code:
contactHelpers.h

Code:

#ifndef contactHelpers_H


#define contactHelpers_H

// Clear the standard input buffer
// clearKeyboard:
void clearKeyboard(void);

// pause:
void pause(void);

// getInt:
int getInt(void);

// getIntInRange:
int getIntInRange(int minRange, int Maxrange);

// yes:
int yes(void);

// menu:
int menu(void);

// ContactManagerSystem:
void ContactManagerSystem(void);

// Generic function to get a ten-digit phone number:
// getTenDigitPhone:
void getTenDigitPhone(char[]);

// findContactIndex:
int findContactIndex(const struct Contact[], int, const char[]);

// displayContactHeader:
void displaycontactHeader(void);

// displayContactFooter:
void displayContactFooter(int);

// displayContact:
void displayContact(const struct Contact*);

// displayContacts:
void displayContacts(const struct Contact[], int);

// searchContacts:
void searchContacts(const struct Contact[], int);

// addContact:
void addContact(struct Contact[], int);

// updateContact:
void updateContact(struct Contact[], int);

// deleteContact:
void deleteContact(struct Contact[], int);

#endif // !contactHelpers_H

contacts.h

Code:

ifndef CONTACTS_H_
#define CONTACTS_H_

#include <stdio.h>


struct Name
{
    char firstName[31];
    char middleName[7];
    char lastName[36];
};

struct Address
{
    int streetNumber;
    char street[41];
    int apartmentNumber;
    char postalCode[8];
    char city[41];
};

struct Numbers
{
    char cell[11];
    char home[11];
    char business[11];
};

struct Contact
{
    struct Name name;
    struct Address address;
    struct Numbers numbers;
};

void displayTitle (void);

void getName (struct Name *);

void getAddress (struct Address *);

void getNumbers (struct Numbers *);

void getContact(struct Contact *);


#endif // !CONTACTS_H_

a2ms4.c

Code:

#define _CRT_SECURE_NO_WARNINGS

#include <stdio.h>
#include "contacts.h"
#include "contactHelpers.h"

void printSectionHeader(const char*);

int main(void)
{
    ContactManagerSystem();

    return 0;
}

// Display specified test section header
void printSectionHeader(const char* testName)
{
    printf("\n");
    printf("------------------------------------------\n");
    printf("Testing: %s\n", testName);
    printf("------------------------------------------\n");
}

contacts.c

Code:

#define _CRT_SECURE_NO_WARNINGS

#include <stdio.h>


#include "contactHelpers.h"
#include "contacts.h"


// getName:
void getName(struct Name * name) {
    int yesNo = 0;
    printf("Please enter the contact's first name: ");
    scanf(" %[^\n]", name->firstName);
    clearKeyboard();
    printf("Do you want to enter a middle initial(s)? (y or n): ");
    yesNo = yes();
    if (yesNo == 1) {
        printf("Please enter the contact's middle initial(s): ");
        scanf(" %[^\n]", name->middleInitial);
        clearKeyboard();
    }

    printf("Please enter the contact's last name: ");
    scanf(" %[^\n]", name->lastName);
    clearKeyboard();
}
// getAddress:
void getAddress(struct Address * address) {
    int yesNo = 0;
    printf("Please enter the contact's street number: ");
    address->streetNumber = getInt();
    if (address->streetNumber > 0) {
    }
    else {
        printf("*** INVALID INTEGER *** <Please enter an integer>: ");
        address->streetNumber = getInt();
    }
    printf("Please enter the contact's street name: ");
    scanf(" %40[^\n]", address->street);
    clearKeyboard();
    printf("Do you want to enter an apartment number? (y or n): ");
    yesNo = yes();
    if (yesNo == 1) {
        printf("Please enter the contact's apartment number: ");
        address->apartmentNumber = getInt();
        if (address->apartmentNumber > 0) {
        }
        else {
            printf("*** INVALID INTEGER *** <Please enter an integer>: ");
            address->apartmentNumber = getInt();
        }
    }
    printf("Please enter the contact's postal code: ");
    scanf(" %7[^\n]", address->postalCode);
    clearKeyboard();
    printf("Please enter the contact's city: ");
    scanf(" %40[^\n]", address->city);
    clearKeyboard();
}

// getNumbers:
void getNumbers(struct Numbers * numbers) {
    int yesNo = 0;
    printf("Please enter the contact's cell phone number: ");
    getTenDigitPhone(numbers->cell);
    printf("Do you want to enter a home phone number? (y or n): ");
    yesNo = yes();
    if (yesNo == 1) {
        printf("Please enter the contact's home phone number: ");
        getTenDigitPhone(numbers->home);
    }

    printf("Do you want to enter a business phone number? (y or n): ");
    yesNo = yes();
    if (yesNo == 1) {
        printf("Please enter the contact's business phone number: ");
        getTenDigitPhone(numbers->business);
    }
}
// getContact:
void getContact(struct Contact * contact) {
    getName(&contact->name);
    getAddress(&contact->address);
    getNumbers(&contact->numbers);
}

contactHelpers.c

Code:

#define _CRT_SECURE_NO_WARNINGS

#include <stdio.h>


#include <string.h>
// ----------------------------------------------------------
#include "contactHelpers.h"
#include "contacts.h"


#define MAXCONTACTS 5


// clearKeyboard
void clearKeyboard(void)
{
    while (getchar() != '\n')
        ; 
}

// pause:
void pause(void)
{
    printf("(Press Enter to Continue)");
    clearKeyboard();
}

// getInt:
int getInt(void)
{
    char NL = 'x';
    int value = 0;
    int boolean = 0;

    scanf(" %d%c", &value, &NL);

    do {
        if (NL != '\n') {
            clearKeyboard();
            printf("*** INVALID INTEGER *** <Please enter an integer>: ");
            scanf(" %d%c", &value, &NL);
            boolean = 1;
        }
        else {
            boolean = 0;
        }
    } while (boolean == 1);
    return value;
}

// getIntInRange:
int getIntInRange(int minRange, int maxRange)
{
    int tstInteger;
    int boolean = 0;

    tstInteger = getInt();
    do {
        if (tstInteger < minRange || tstInteger > maxRange) {
            printf("*** OUT OF RANGE *** <Enter a number between %d and %d>: ", minRange, maxRange);
            tstInteger = getInt();
            boolean = 1;
        }
        else {
            boolean = 0;
        }
    } while (boolean != 0);
    return tstInteger;
}

// yes:
int yes(void)
{
    int boolean = 0;
    int result = 0;
    char input;
    char NL = 'x';
    do {
        scanf(" %c%c", &input, &NL);

        if (NL != '\n') {
            printf("*** INVALID ENTRY *** <Only (Y)es or (N)o are acceptable>: ");
            boolean = 1;
        }
        else {
            switch (input) {
            case 'Y':
            case 'y':
                result = 1;
                boolean = 0;
                break;
            case 'N':
            case'n':
                result = 0;
                boolean = 0;
                break;
            }
        }
    } while (boolean == 1);
    return result;
}

// menu:
int menu(void)
{
    int input = 0;
    printf("Contact Management System\n");
    printf("-------------------------\n");
    printf("1. Display contacts\n");
    printf("2. Add a contact\n");
    printf("3. Update a contact\n");
    printf("4. Delete a contact\n");
    printf("5. Search contacts by cell phone number\n");
    printf("6. Sort contacts by cell phone number\n");
    printf("0. Exit\n\n");
    printf("Select an option:> ");

    input = getIntInRange(0, 6);
    printf("\n");

    return input;
}

// ContactManagerSystem:
void ContactManagerSystem(void)
{
    struct Contact contact[MAXCONTACTS] =
    { { { "Rick",{ '\0' }, "Grimes" },
    { 11, "Trailer Park", 0, "A7A 2J2", "King City" },
    { "4161112222", "2162223333", "4163334444" } },
    {
        { "Maggie", "R.", "Greene" },
        { 55, "Hightop House", 0, "A9A 3K3", "Bolton" },
        { "9051112222", "9052223333", "9053334444" } },
        {
            { "Morgan", "A.", "Jones" },
            { 77, "Cottage Lane", 0, "C7C 9Q9", "Peterborough" },
            { "7051112222", "7052223333", "7053334444" } },
            {
                { "Sasha",{ '\0' }, "Williams" },
                { 55, "Hightop House", 0, "A9A 3K3", "Bolton" },
                { "9052223333", "9052223333", "9054445555" } },
    };

    int menuInput = 0;
    int exitInput = 0;
    int boolean = 0;

    do {
        menuInput = menu();
        switch (menuInput) {
        case 1:
            displayContacts(contact, MAXCONTACTS);
            pause();
            printf("\n");
            break;
        case 2:
            addContact(contact, MAXCONTACTS);
            pause();
            printf("\n");
            break;
        case 3:
            updateContact(contact, MAXCONTACTS);
            pause();
            printf("\n");
            break;
        case 4:
            deleteContact(contact, MAXCONTACTS);
            pause();
            printf("\n");
            break;
        case 5:
            searchContacts(contact, MAXCONTACTS);
            pause();
            printf("\n");
            break;
        case 6:
            printf("<<< Feature to sort is unavailable >>>\n");
            pause();
            break;
        case 0:
            printf("Exit the program? (Y)es/(N)o: ");
            exitInput = yes();
            printf("\n");
            if (exitInput == 1) {
                printf("Contact Management System: terminated");
                printf("\n");
                boolean = 1;
            }
        }
    } while (boolean == 0);
}

// getTenDigitPhone
void getTenDigitPhone(char telNum[11])
{
    int needInput = 1;

    while (needInput == 1) {
        scanf("%10s", telNum);
        clearKeyboard();

        if (strlen(telNum) == 10)
            needInput = 0;
        else
            printf("Enter a 10-digit phone number: ");
    }
}

// findContactIndex:
int findContactIndex(const struct Contact contact[], int size, const char cellNum[])
{
    int i = 0;
    int output;
    for (i = 0; i < size; i++) {
        output = strcmp(contact[i].numbers.cell, cellNum);
        if (output == 0) {
            return i;
        }
    }
    return -1;
}

// displayContactHeader
void displayContactHeader(void) {
    printf("+-----------------------------------------------------------------------------+\n");
    printf("|                              Contacts Listing                               |\n");
    printf("+-----------------------------------------------------------------------------+\n");
}

// displayContactFooter
void displayContactFooter(int totalContact) {
    printf("+-----------------------------------------------------------------------------+\n");
    printf("Total contacts: %d\n\n", totalContact);
}

// displayContact:
void displayContact(const struct Contact* contact) {
    if (contact->name.middleInitial[0] != '\0') {
        printf("%s %s %s\n", contact->name.firstName, contact->name.middleInitial, contact->name.lastName);
    }
    else {
        printf("%s %s\n", contact->name.firstName, contact->name.lastName);
    }
    printf("    C: %-10s    H: %-10s    B: %-10s\n", contact->numbers.cell, contact->numbers.home, contact->numbers.business);
    printf("       %d %s, ", contact->address.streetNumber, contact->address.street);
    if (contact->address.apartmentNumber > 0) {
        printf("Apt# %d, ", contact->address.apartmentNumber);
    }
    printf("%s, %s\n", contact->address.city, contact->address.postalCode);
}

// displayContacts:
void displayContacts(const struct Contact contact[], int num) {
    int i;
    int totalContact = 0;

    displayContactHeader();

    for (i = 0; i < num; i++) {
        if (strlen(contact[i].numbers.cell) > 0) {
            displayContact(&contact[i]);
            totalContact++;
        }
    }
    displayContactFooter(totalContact);
}

// searchContacts:
void searchContacts(const struct Contact contact[], int num) {
    char cellNum[11];
    int contactIndex = 0;

    printf("Enter the cell number for the contact: ");
    getTenDigitPhone(cellNum);
    contactIndex = findContactIndex(contact, num, cellNum);

    if (contactIndex == -1) {
        printf("*** Contact NOT FOUND ***\n");
    }
    else {
        printf("\n");
        displayContact(&contact[contactIndex]);
        printf("\n");
    }
}

// addContact:
void addContact(struct Contact contact[], int num) {
    char emptyIndex[11] = { '\0' };
    int newContact;
    struct Contact tempContact = { { { 0 } } };

    newContact = findContactIndex(contact, num, emptyIndex);

    if (newContact != -1) {
        getContact(&tempContact);
        contact[newContact] = tempContact;
        printf("--- New contact added! ---\n");
    }
    else {
        printf("*** ERROR: The contact list is full! ***\n");
    }
}

// updateContact:
void updateContact(struct Contact contact[], int i) {
    char contactInput[11] = { '\0' };
    int input = 0;
    int contactIndex;
    int contactIn;
    printf("Enter the cell phone number for the contact: ");
    getTenDigitPhone(contactInput);
    contactIndex = findContactIndex(contact, i, contactInput);
    contactIn = findContactIndex(contact, i, contactInput);

    if (contactIn == -1) {
        printf("*** Contact NOT FOUND ***\n");
    }
    else {
        printf("\nContact found:\n");
        displayContact(&contact[contactIndex]);

        printf("Do you want to update the name? (y or n): ");
        input = yes();

        if (input == 1) {
            getName(&contact[contactIndex].name);
        }
        printf("Do you want to update the address? (y or n): ");
        input = yes();

        if (input == 1) {
            getAddress(&contact[contactIndex].address);
        }
        printf("Do you want to update the numbers? (y or n): ");
        input = yes();

        if (input == 1) {
            getNumbers(&contact[contactIndex].numbers);
        }

        printf("--- Contact Updated! ---\n");
    }
}

// deleteContact:
void deleteContact(struct Contact contact[], int i) {
    char contactInput[11] = { '\0' };
    int input = 0;
    int contactIndex;

    printf("Enter the cell phone number for the contact: ");
    getTenDigitPhone(contactInput);

    contactIndex = findContactIndex(contact, i, contactInput);

    if (contactIndex == -1)
        printf("*** Contact NOT FOUND ***\n");

    else {
        printf("\nContact found:\n");

        displayContact(&contact[contactIndex]);
        printf("\n");

        printf("CONFIRM: Delete this contact? (y or n): ");
        input = yes();

        if (input == 1) {
            contact[contactIndex].numbers.cell[0] = '\0';
            printf("--- Contact deleted! ---\n");
        }
    }
}

how can I fix my errors? thank you for the help!

Originally Posted by Salem

Check the order you include files.

Thank you it worked, can't believe I spent hours on that. I need more practice, still a newb.