[parisc-linux] The printf fiasco

[Matthew Wilcox]

On Mon, Mar 26, 2001 at 12:55:38AM +0100, Alan Cox wrote:
> Actually you cant take the address. Instead your 
> 
> 	(void *)printf
> 
> generates
> 	(void *)fprintf
> 
> and your program core dumps mysteriously at run time

No it doesn't.

# cat ./def-test.c 
#include <stdio.h>

int main(void)
{
        void *a = (void *)printf;
        void *b = (void *)fprintf;
#undef printf
        void *c = (void *)printf;

        printf("a = %p, b = %p, c = %p\n", a, b, c);
        return 0;
}

# gcc -O2 -Wall -W def-test.c -o def-test
# gcc --version
3.0
# ./def-test 
a = 0x26f2, b = 0x271a, c = 0x26f2

that's because

# if __GNUC_PREREQ (2,97)
#  define printf(fmt, args...) fprintf (stdout, fmt, ##args)
# endif

doesn't match printf, but only printf(...)

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