On 23/02/19 12:49, Natanael Copa wrote:
> I suspect this happens due to the Alpine toolchain will enable
> _FORTIFY_SOURCE=2 by default and the way this is implemented via
> fortify-headers:
> http://git.2f30.org/fortify-headers/file/include/string.h.html#l39
The call to __orig_memcpy is the culprit there, is there any reason not
to do something like
_FORTIFY_FN(memcpy)
void *__memcpy_chk(void *__od, const void *__os, size_t __n)
{
size_t __bd = __builtin_object_size(__od, 0);
size_t __bs = __builtin_object_size(__os, 0);
char *__d = (char *)__od;
const char *__s = (const char *)__os;
/* trap if pointers are overlapping but not if dst == src.
* gcc seems to like to generate code that relies on dst == src */
if ((__d < __s && __d + __n > __s) ||
(__s < __d && __s + __n > __d))
__builtin_trap();
if (__n > __bd || __n > __bs)
__builtin_trap();
return memcpy(__od, __os, __n);
}
#define memcpy __memcpy_chk
? That is, getting rid of _FORTIFY_ORIG altogether.
Paolo
