http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49330
--- Comment #1 from Harald van Dijk <harald at gigawatt dot nl> 2011-06-08 20:42:04 UTC --- A similar example, but one which does not convert the integer back to a pointer: #include <stdio.h> #include <stdlib.h> int a; int main() { unsigned long b = (unsigned long) &a - 134518548; volatile unsigned long c = b; if (c == 0) { if (b != 0) abort (); } printf("%lu\n", c); return a; } This should never abort. It aborts on my system (with -m32).