start = (char*) Perl_get_arena(aTHX_ arena_size, sv_type);
- end = start + arena_size - 2 * body_size;
+ /* Get the address of the byte after the end of the last body we can fit.
+ Remember, this is integer division: */
+ end = start + arena_size / body_size * body_size;
/* computed count doesnt reflect the 1st slot reservation */
#if defined(MYMALLOC) || defined(HAS_MALLOC_GOOD_SIZE)
#endif
*root = (void *)start;
- while (start <= end) {
+ while (1) {
+ /* Where the next body would start: */
char * const next = start + body_size;
+
+ if (next >= end) {
+ /* This is the last body: */
+ assert(next == end);
+
+ *(void **)start = 0;
+ return *root;
+ }
+
*(void**) start = (void *)next;
start = next;
}
- *(void **)start = 0;
-
- return *root;
}
/* grab a new thing from the free list, allocating more if necessary.