+ unsigned long ul_size = (unsigned long) size;
+
+ if (size != ul_size
+ /* Note - although objalloc_alloc takes an unsigned long as its
+ argument, internally the size is treated as a signed long. This can
+ lead to problems where, for example, a request to allocate -1 bytes
+ can result in just 1 byte being allocated, rather than
+ ((unsigned long) -1) bytes. Also memory checkers will often
+ complain about attempts to allocate a negative amount of memory.
+ So to stop these problems we fail if the size is negative. */
+ || ((signed long) ul_size) < 0)