- fprintf(stderr,
- "ensure_space: failed to validate %ld bytes at 0x%08lx\n",
- size,
- (unsigned long)start);
- fprintf(stderr,
- "(hint: Try \"ulimit -a\"; maybe you should increase memory limits.)\n");
- exit(1);
+ fprintf(stderr,
+ "ensure_space: failed to validate %ld bytes at 0x%08lx\n",
+ size,
+ (unsigned long)start);
+ fprintf(stderr,
+ "(hint: Try \"ulimit -a\"; maybe you should increase memory limits.)\n");
+ exit(1);
+ }
+}
+
+os_vm_address_t undefined_alien_address = 0;
+
+static void
+ensure_undefined_alien(void) {
+ os_vm_address_t start = os_validate(NULL, os_vm_page_size);
+ if (start) {
+ os_protect(start, os_vm_page_size, OS_VM_PROT_NONE);
+ undefined_alien_address = start;
+ } else {
+ lose("could not allocate guard page for undefined alien\n");