Julian Seward 31b741dc9b Merge the Ptrcheck tool from branches/PTRCHECK r8619.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@8620
2008-09-18 14:43:05 +00:00

28 lines
698 B
C

#include <stdlib.h>
// The comparisons use SUB instructions, and this can result in having a
// (nonptr - ptr) situation legitimately; at one point I was flagging
// errors when that happened.
int main(void)
{
char* buf = malloc(sizeof(char) * 6);
// Known zero non-pointer
char* nz = (char*)((long)buf^(long)buf); // known non-pointer
// Unknown zero nonptr; make them zero but unknown
char* unz;
((char*)&unz)[0] = '\0';
((char*)&unz)[1] = '\0';
((char*)&unz)[2] = '\0';
((char*)&unz)[3] = '\0';
if (buf == nz) return 1;
if (nz == buf) return 1; // --> n - p, but legitimate
if (buf == unz) return 1;
if (unz == buf) return 1;
return 0;
}