Displaying 1 result from an estimated 1 matches for "zerosizeptr".
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zero_size_ptr
2006 Dec 11
2
malloc(0) returns 0x800 on FreeBSD 6.2 ?
...n
by this program:
> more a.c
#include <stdio.h>
int main(int argc, char *argv[])
{
char *p = malloc(0);
printf(" malloc 0 returns %p\n", p);
}
> cc -o a a.c
> ./a
malloc 0 returns 0x800
if you look at the source this is indeed clear - internally
the 0x800 is ZEROSIZEPTR and is set when a zero length is
passed to malloc() unless you have malloc_sysv set.
The thing is, i don't know if this behaviour is intentional or not,
but certainly is not documented -- the manpage documents
something totally different (in the section for the 'V'
MALLOC_OPTION, see b...