* futures.h, futures.c: Wrap whole contents in "#if 0"/"#endif".

* eval.c, init.c: Comment out all 'future' related things.

libguile/eval.c

@@ -2102,6 +2102,10 @@ unmemoize_at_call_with_values (const SCM expr, const SCM env)
                      unmemoize_exprs (SCM_CDR (expr), env));
 }
 
+#if 0
+
+/* See futures.h for a comment why futures are not enabled.
+ */
 
 SCM_SYNTAX (s_future, "future", scm_i_makbimacro, scm_m_future);
 SCM_GLOBAL_SYMBOL (scm_sym_future, s_future);
@@ -2126,6 +2130,7 @@ unmemoize_future (const SCM expr, const SCM env)
   return scm_list_2 (scm_sym_future, unmemoize_expression (thunk_expr, env));
 }
 
+#endif
 
 SCM_SYNTAX (s_gset_x, "set!", scm_i_makbimacro, scm_m_generalized_set_x);
 SCM_SYMBOL (scm_sym_setter, "setter");
@@ -2393,8 +2398,12 @@ unmemoize_builtin_macro (const SCM expr, const SCM env)
     case (ISYMNUM (SCM_IM_CALL_WITH_VALUES)):
       return unmemoize_at_call_with_values (expr, env);
 
+#if 0
+    /* See futures.h for a comment why futures are not enabled.
+     */
     case (ISYMNUM (SCM_IM_FUTURE)):
       return unmemoize_future (expr, env);
+#endif
 
     case (ISYMNUM (SCM_IM_SLOT_REF)):
       return unmemoize_atslot_ref (expr, env);
@@ -3748,10 +3757,12 @@ dispatch:
 	case (ISYMNUM (SCM_IM_DELAY)):
 	  RETURN (scm_makprom (scm_closure (SCM_CDR (x), env)));
 
-
+#if 0
+	  /* See futures.h for a comment why futures are not enabled.
+	   */
 	case (ISYMNUM (SCM_IM_FUTURE)):
 	  RETURN (scm_i_make_future (scm_closure (SCM_CDR (x), env)));
-
+#endif
 
 	  /* PLACEHOLDER for case (ISYMNUM (SCM_IM_DISPATCH)): The following
 	     code (type_dispatch) is intended to be the tail of the case

libguile/futures.c

@@ -18,6 +18,12 @@
 
 
 
+#if 0
+
+/* This whole file is not being compiled.  See futures.h for the
+   reason.
+*/
+
 #include "libguile/_scm.h"
 #include "libguile/eval.h"
 #include "libguile/ports.h"
@@ -360,6 +366,8 @@ scm_init_futures ()
 #include "libguile/futures.x"
 }
 
+#endif
+
 /*
   Local Variables:
   c-file-style: "gnu"

libguile/futures.h

@@ -22,6 +22,18 @@
 
 
 
+#if 0
+
+/* Futures have the following known bugs, which should be fixed before
+   including them in Guile:
+
+   - The implementation of the thread cache needs to be better so that
+     it behaves reasonable under heavy use.
+
+   - The dynamic state of a thread needs to be properly initialized
+     when it is retrieved from the cache.
+*/
+
 #include "libguile/__scm.h"
 #include "libguile/threads.h"
 
@@ -67,6 +79,8 @@ SCM_API SCM scm_future_ref (SCM future);
 
 void scm_init_futures (void);
 
+#endif  /* Futures are disabled for now. */
+
 #endif  /* SCM_FUTURES_H */
 
 /*

libguile/init.c

@@ -455,7 +455,11 @@ scm_i_init_guile (SCM_STACKITEM *base)
   scm_init_dynwind ();
   scm_init_eq ();
   scm_init_error ();
+#if 0
+  /* See futures.h for a comment why futures are not enabled.
+   */
   scm_init_futures ();
+#endif
   scm_init_fluids ();
   scm_init_feature ();          /* Requires fluids */
   scm_init_backtrace ();	/* Requires fluids */