Simplify thread initialization and GC

* src/lisp.h (PVECHEADERSIZE): New macro.
(XSETPVECTYPESIZE): Use it.
* src/search.c (syms_of_search): No need to initialize or
staticpro last_thing_searched or saved_last_thing_searched, as
the thread code arranges for initialization and GC.
* src/thread.c (main_thread): Initialize statically.
(Fmake_mutex, Fmake_condition_variable, Fmake_thread):
Use ALLOCATE_ZEROED_PSEUDOVECTOR rather than zeroing by hand.
(mark_one_thread): No need to mark Lisp_Object members.
(init_main_thread, init_threads_once): Remove.  All uses removed.

1 files changed, 0 insertions, 6 deletions

diff --git a/src/search.c b/src/search.c
index 7a6e680685a..dfbae5c9628 100644
--- a/src/search.c
+++ b/src/search.c
@@ -3387,12 +3387,6 @@ syms_of_search (void)
   Fput (Qinvalid_regexp, Qerror_message,
         build_pure_c_string ("Invalid regexp"));
 
-  last_thing_searched = Qnil;
-  staticpro (&last_thing_searched);
-
-  saved_last_thing_searched = Qnil;
-  staticpro (&saved_last_thing_searched);
-
   re_match_object = Qnil;
   staticpro (&re_match_object);