[En-Nut-Discussion] H8/300 Question: Print Format Specifier For size_t

[Jan Dubiec]

On Wed, 17 Mar 2004 18:20:09 +0100, Harald Kipp <harald.kipp at egnite.de> wrote:
> In the H8 port, several format specifiers have been
> changed from %X to %lX.
> 
> Example, found in app/httpserv.c
> 
> #if defined(__AVR_ATmega128__) || defined(__AVR_ATmega103__)
>          printf("[%u] Connected, %u bytes free\n", id, NutHeapAvailable());
> #else
>          printf("[%u] Connected, %lu bytes free\n", id, NutHeapAvailable());
> #endif
> 
> 
> Is that really required? Isn't size_t (like int) 32 bit by
> default?
Yes, size_t is 32 bit but when I tried to compile the original code
using h8300-elf-gcc (or arm-elf-gcc) I got following warning:

httpserv.c:442: warning: unsigned int format, size_t arg (arg 3)

As an example you may try to compile following program using one of
the mentioned compilers with -Wall option.

#include <stdio.h>
#include <stddef.h>

int main(int argc, char *argv[])
{
    size_t i = 10;

    printf("size_t = %u\n", sizeof(size_t));

    printf("i (%%d) = %d\n", i);
    printf("i (%%u) = %u\n", i);

    printf("i (%%ld) = %ld\n", i);
    printf("i (%%lu) = %lu\n", i);

    return 0;
}

BTW. Maybe we should use type casting instead of defines in such places? 

Regards,
/J.D.
-- 
Jan Dubiec, jdx at slackware.pl, mobile: +48 602 101787

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