Strange C behaviour

[Michael Meskes <meskes@debian.org>]

Could anyone explain this to me?

Here's the program:

#include <stdio.h>

main()
{
	char ptr[10];
	
	printf("%p %p\n", ptr, &ptr);
}

And the output:

0xbffffbf0 0xbffffbf0

Or in other words, the '&' operator does not do anything. In particular that
means that the following program will dump core:

#include <stdio.h>
#include <stdarg.h>

void set(int s, ...)
{
	va_list args;
	void *p;	
	
	va_start(args, s);
	p = va_arg(args, void *);
	**((char **)p) = 'm';
	va_end(args);
}

void test1(ptr)
char ptr[];
{
	printf ("test1: ptr=%p %p\n", ptr, &ptr);
	set(1, &ptr);
	printf ("test1: ptr=%p\n", ptr);
}

main()
{
	char ptr[14];
	
	printf("main: ptr=%p\n", ptr);
	test1(ptr);
	set(2, &ptr);
	printf("main: ptr=%p\n", ptr);
}

So how do I call set() correctly so that it works from main() as well as from
test1()?

Michael
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