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cpointersprintfc-stringsconversion-specifier

How to fix warning "Format specifies type 'void *' but the argument has type 'char' warning"


I am getting the output that I want but can't figure out how to get rid of these warnings. Any help is appreciated.

Warnings:

  1. Format specifies type 'void *' but the argument has type 'char' [-Wformat] printf("\nThe pointer variable's value is %p\n", *myString);

  2. "Format specifies type 'void *' but the argument has type 'char' [-Wformat] printf("%p\n", myString[x]);

     #include <stdio.h>
     #include <stdlib.h>
    
     int main() {
    
       char *myString = "Daniel";
       int x;
    
       printf("\nThe pointer variable's value is %p\n", *myString);
       printf("\nThe pointer variable points to %s\n", myString);
       printf("\nThe memory location for each character are: \n");
    
    
       for (x = 0;x < 7;x++){
        printf("%p\n", myString[x]);
       }
    
     return 0;
     }
    

Ouput:

     The pointer variable's value is 0x44

     The pointer variable points to Daniel

     The memory location for each character are: 
     0x44
     0x61
     0x6e
     0x69
     0x65
     0x6c
     (nil)

Solution

  • For starters these calls

    printf("\nThe pointer variable's value is %p\n", *myString);
    

    and

    printf("%p\n", myString[x]);
    

    do not make sense because you are trying to use a value of a character as a pointer value.

    As for the other warning then just cast pointers to the type void *. For example

    printf("\nThe pointer variable's value is %p\n", ( void * )myString);
    printf("\nThe pointer variable points to %s\n", myString);
    printf("\nThe memory location for each character are: \n");
    
    
    for (x = 0;x < 7;x++){
     printf("%p\n", ( void * )( myString + x ));
    }