diff --git a/src/mzscheme/src/jit.c b/src/mzscheme/src/jit.c
index 0f73cf4cf9..2d66a54733 100644
--- a/src/mzscheme/src/jit.c
+++ b/src/mzscheme/src/jit.c
@@ -2232,6 +2232,7 @@ static void ts_on_demand(void)
 # define mz_direct_only(p) p
 # define ts_scheme_apply_multi_from_native _scheme_apply_multi_from_native
 # define ts_scheme_apply_from_native _scheme_apply_from_native
+# define ts_scheme_tail_apply_from_native _scheme_tail_apply_from_native
 # define ts_on_demand on_demand
 #endif
 
diff --git a/src/mzscheme/src/mzmark.c b/src/mzscheme/src/mzmark.c
index 9736a6962d..236a9f1011 100644
--- a/src/mzscheme/src/mzmark.c
+++ b/src/mzscheme/src/mzmark.c
@@ -5419,7 +5419,7 @@ static int future_SIZE(void *p) {
 }
 
 static int future_MARK(void *p) {
-  future_t *c = (future_t *)p;
+  future_t *f = (future_t *)p;
   gcMARK(f->runstack);
   gcMARK(f->runstack_start);
   gcMARK(f->orig_thread);
@@ -5433,7 +5433,7 @@ static int future_MARK(void *p) {
 }
 
 static int future_FIXUP(void *p) {
-  future_t *c = (future_t *)p;
+  future_t *f = (future_t *)p;
   gcFIXUP(f->runstack);
   gcFIXUP(f->runstack_start);
   gcFIXUP(f->orig_thread);
diff --git a/src/mzscheme/src/mzmarksrc.c b/src/mzscheme/src/mzmarksrc.c
index 7ca1896486..2747210bd8 100644
--- a/src/mzscheme/src/mzmarksrc.c
+++ b/src/mzscheme/src/mzmarksrc.c
@@ -2222,7 +2222,7 @@ START future;
 
 future {
  mark:
-  future_t *c = (future_t *)p;
+  future_t *f = (future_t *)p;
   gcMARK(f->runstack);
   gcMARK(f->runstack_start);
   gcMARK(f->orig_thread);
diff --git a/src/mzscheme/src/schemex.h b/src/mzscheme/src/schemex.h
index 7bc7e0031b..be20335c54 100644
--- a/src/mzscheme/src/schemex.h
+++ b/src/mzscheme/src/schemex.h
@@ -54,7 +54,7 @@ Scheme_Object *(*scheme_current_break_cell)();
 /*                                threads                                 */
 /*========================================================================*/
 #ifndef LINK_EXTENSIONS_BY_TABLE
-# ifndef MZ_USE_PLACES
+# if !defined(MZ_USE_PLACES) || !defined(FUTURES_ENABLED)
 Scheme_Thread *scheme_current_thread;
 # endif
 volatile int scheme_fuel_counter;
diff --git a/src/mzscheme/src/schemex.inc b/src/mzscheme/src/schemex.inc
index 6ac238295f..35233fda6e 100644
--- a/src/mzscheme/src/schemex.inc
+++ b/src/mzscheme/src/schemex.inc
@@ -19,7 +19,7 @@
   scheme_extension_table->scheme_inherit_cells = scheme_inherit_cells;
   scheme_extension_table->scheme_current_break_cell = scheme_current_break_cell;
 #ifndef LINK_EXTENSIONS_BY_TABLE
-# ifndef MZ_USE_PLACES
+# if !defined(MZ_USE_PLACES) || !defined(FUTURES_ENABLED)
   scheme_extension_table->scheme_current_thread = scheme_current_thread;
 # endif
   scheme_extension_table->scheme_fuel_counter = scheme_fuel_counter;
diff --git a/src/mzscheme/src/schemexm.h b/src/mzscheme/src/schemexm.h
index b31346f008..ba5deb8927 100644
--- a/src/mzscheme/src/schemexm.h
+++ b/src/mzscheme/src/schemexm.h
@@ -19,7 +19,7 @@
 #define scheme_inherit_cells (scheme_extension_table->scheme_inherit_cells)
 #define scheme_current_break_cell (scheme_extension_table->scheme_current_break_cell)
 #ifndef LINK_EXTENSIONS_BY_TABLE
-# ifndef MZ_USE_PLACES
+# if !defined(MZ_USE_PLACES) || !defined(FUTURES_ENABLED)
 #define scheme_current_thread (scheme_extension_table->scheme_current_thread)
 # endif
 #define scheme_fuel_counter (scheme_extension_table->scheme_fuel_counter)