Compile disabled code for thread cache always

thread.c

@@ -5437,6 +5437,9 @@ Init_Thread(void)
     rb_thread_create_timer_thread();
 
     Init_thread_sync();
+
+    // TODO: Suppress unused function warning for now
+    if (0) rb_thread_sched_destroy(NULL);
 }
 
 int

thread_none.c

@@ -46,12 +46,10 @@ rb_thread_sched_init(struct rb_thread_sched *sched)
 {
 }
 
-#if 0
 static void
 rb_thread_sched_destroy(struct rb_thread_sched *sched)
 {
 }
-#endif
 
 // Do nothing for mutex guard
 void

thread_pthread.c

@@ -617,7 +617,6 @@ rb_thread_sched_init(struct rb_thread_sched *sched)
     sched->wait_yield = 0;
 }
 
-#if 0
 // TODO
 
 static void clear_thread_cache_altstack(void);
@@ -637,7 +636,6 @@ rb_thread_sched_destroy(struct rb_thread_sched *sched)
     }
     clear_thread_cache_altstack();
 }
-#endif
 
 #if defined(HAVE_WORKING_FORK)
 static void thread_cache_reset(void);
@@ -747,8 +745,12 @@ Init_native_thread(rb_thread_t *main_th)
     native_thread_init(main_th->nt);
 }
 
-#ifndef USE_THREAD_CACHE
-#define USE_THREAD_CACHE 1
+#if defined(USE_THREAD_CACHE) && !(USE_THREAD_CACHE+0)
+# undef USE_THREAD_CACHE
+# define USE_THREAD_CACHE 0
+#else
+# undef USE_THREAD_CACHE
+# define USE_THREAD_CACHE 1
 #endif
 
 static void
@@ -1092,10 +1094,7 @@ thread_start_func_1(void *th_ptr)
 #endif
 
     RB_ALTSTACK_INIT(void *altstack, th->nt->altstack);
-#if USE_THREAD_CACHE
-  thread_start:
-#endif
-    {
+    do {
 #if !defined USE_NATIVE_THREAD_INIT
         VALUE stack_start;
 #endif
@@ -1114,15 +1113,12 @@ thread_start_func_1(void *th_ptr)
 #else
         thread_start_func_2(th, &stack_start);
 #endif
+    } while (USE_THREAD_CACHE &&
+             /* cache thread */
+             (th = register_cached_thread_and_wait(RB_ALTSTACK(altstack))) != 0);
+    if (!USE_THREAD_CACHE) {
+        RB_ALTSTACK_FREE(altstack);
     }
-#if USE_THREAD_CACHE
-    /* cache thread */
-    if ((th = register_cached_thread_and_wait(RB_ALTSTACK(altstack))) != 0) {
-        goto thread_start;
-    }
-#else
-    RB_ALTSTACK_FREE(altstack);
-#endif
     return 0;
 }
 
@@ -1196,7 +1192,8 @@ static void thread_cache_reset(void) { }
 static int
 use_cached_thread(rb_thread_t *th)
 {
-#if USE_THREAD_CACHE
+    if (!USE_THREAD_CACHE) return 0;
+
     struct cached_thread_entry *entry;
 
     rb_native_mutex_lock(&thread_cache_lock);
@@ -1209,16 +1206,14 @@ use_cached_thread(rb_thread_t *th)
     }
     rb_native_mutex_unlock(&thread_cache_lock);
     return !!entry;
-#endif
-    return 0;
 }
 
-#if 0
 // TODO
 static void
 clear_thread_cache_altstack(void)
 {
-#if USE_THREAD_CACHE
+    if (!USE_THREAD_CACHE) return;
+
     struct cached_thread_entry *entry;
 
     rb_native_mutex_lock(&thread_cache_lock);
@@ -1228,9 +1223,7 @@ clear_thread_cache_altstack(void)
         RB_ALTSTACK_FREE(altstack);
     }
     rb_native_mutex_unlock(&thread_cache_lock);
-#endif
 }
-#endif
 
 static struct rb_native_thread *
 native_thread_alloc(void)

thread_win32.c

@@ -154,14 +154,12 @@ rb_thread_sched_init(struct rb_thread_sched *sched)
     sched->lock = w32_mutex_create();
 }
 
-#if 0
 void
 rb_thread_sched_destroy(struct rb_thread_sched *sched)
 {
     if (GVL_DEBUG) fprintf(stderr, "sched destroy\n");
     CloseHandle(sched->lock);
 }
-#endif
 
 rb_thread_t *
 ruby_thread_from_native(void)