Fix glitches in recent hash table changes

* src/fns.c (Fmake_hash_table): Simplify the machine code slightly
by using 0 rather than -1.
* src/lisp.h (struct Lisp_Hash_Table.pure): Now bool rather
than a bitfield, for speed (the bitfield did not save space).
(struct Lisp_Hash_Table.rehash_threshold): Now double rather than
float, since the float caused unwanted rounding errors, e.g.,
(hash-table-rehash-threshold (make-hash-table)) yielded
0.800000011920929 instead of the correct 0.8.

1 files changed, 2 insertions, 3 deletions

diff --git a/src/fns.c b/src/fns.c
index be00bfd8681..3fed92dfec1 100644
--- a/src/fns.c
+++ b/src/fns.c
@@ -4445,9 +4445,8 @@ usage: (make-hash-table &rest KEYWORD-ARGS)  */)
 
   /* Look for `:rehash-threshold THRESHOLD'.  */
   i = get_key_arg (QCrehash_threshold, nargs, args, used);
-  rehash_threshold =
-    i ? (FLOATP (args[i]) ? XFLOAT_DATA (args[i]) : -1.0)
-    : DEFAULT_REHASH_THRESHOLD;
+  rehash_threshold = (!i ? DEFAULT_REHASH_THRESHOLD
+                      : FLOATP (args[i]) ? XFLOAT_DATA (args[i]) : 0);
   if (! (0 < rehash_threshold && rehash_threshold <= 1))
     signal_error ("Invalid hash table rehash threshold", args[i]);