Use ptrdiff_t instead of Lisp_Object for collision

* src/alloc.c (purecopy_hash_table): Assign, don’t purecopy.
* src/fns.c (set_hash_next_slot, set_hash_index_slot): Hash index
arg is now ptrdiff_t index (or -1 if empty), not Lisp_Object
integer (or Qnil if empty).  All callers changed.
(larger_vecalloc): New static function.
(larger_vector): Use it.
(HASH_NEXT, HASH_INDEX): Move here from lisp.h.  Return ptrdiff_t
index (or -1) not Lisp_Object integer (or Qnil).  All callers changed.
* src/fns.c (make_hash_table, maybe_resize_hash_table, hash_lookup)
(hash_put, hash_remove_from_table, hash_clear, sweep_weak_table):
* src/profiler.c (evict_lower_half, record_backtrace):
-1, not nil, is now the convention for end of collision list.
* src/fns.c (maybe_resize_hash_table): Avoid double-initialization
of the free list.  Reallocate H->next last, in case other
reallocations exhaust memory.
* src/lisp.h (struct Lisp_Hash_Table): ‘next_free’ is now
ptrdiff_t, not Lisp_Object.  Adjust commentary for ‘next’ and
‘index’, which no longer contain nil.
(HASH_NEXT, HASH_INDEX): Move to src/fns.c.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/alloc.c b/src/alloc.c
index b579e7ed1ae..5da4290701e 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -5459,7 +5459,7 @@ purecopy_hash_table (struct Lisp_Hash_Table *table)
   pure->rehash_size = purecopy (table->rehash_size);
   pure->hash = purecopy (table->hash);
   pure->next = purecopy (table->next);
-  pure->next_free = purecopy (table->next_free);
+  pure->next_free = table->next_free;
   pure->index = purecopy (table->index);
   pure->count = table->count;
   pure->pure = table->pure;