diff --git a/racket/src/racket/src/jitcommon.c b/racket/src/racket/src/jitcommon.c
index 4e1addb40a..b016422b19 100644
--- a/racket/src/racket/src/jitcommon.c
+++ b/racket/src/racket/src/jitcommon.c
@@ -877,6 +877,8 @@ static int common2(mz_jit_state *jitter, void *_data)
   jit_jmpr(JIT_R2);
   CHECK_LIMIT();
 
+  scheme_jit_register_sub_func(jitter, sjc.stack_cache_pop_code, scheme_false);
+
   /* *** bad_app_vals_target *** */
   /* Non-proc is in R0 */
   sjc.bad_app_vals_target = jit_get_ip();
diff --git a/racket/src/racket/src/jitstack.c b/racket/src/racket/src/jitstack.c
index 9b54edadc8..81c219134b 100644
--- a/racket/src/racket/src/jitstack.c
+++ b/racket/src/racket/src/jitstack.c
@@ -161,10 +161,10 @@ static void set_cache(void *p, Scheme_Object *last)
 
 Scheme_Object *scheme_native_stack_trace(void)
 {
-  void *p, *q, *prev_frame_p;
+  void *p, *q, *cache_frame_p;
   uintptr_t stack_end, real_stack_end, stack_start, halfway;
   Scheme_Object *name, *last = NULL, *first = NULL, *tail;
-  int prev_had_name = 0;
+  int cache_had_name = 0;
 #ifdef MZ_USE_DWARF_LIBUNWIND
   unw_context_t cx;
   unw_cursor_t c;
@@ -318,15 +318,14 @@ Scheme_Object *scheme_native_stack_trace(void)
   }
 #endif
 
-  prev_frame_p = NULL;
+  cache_frame_p = NULL;
 
   while (unsuccess < UNKNOWN_FRAME_LIMIT) {
 #ifdef MZ_USE_DWARF_LIBUNWIND
-    if (use_unw) {
+    if (use_unw)
       q = (void *)unw_get_ip(&c);
-    } else {
+    else
       q = NULL;
-    }
 #endif
 
     if (!use_unw) {
@@ -407,6 +406,21 @@ Scheme_Object *scheme_native_stack_trace(void)
         name = NULL;
     }
 
+#ifdef MZ_USE_DWARF_LIBUNWIND
+    if (use_unw) {
+      if (manual_unw) {
+	cache_frame_p = (void **)unw_get_frame_pointer(&c);
+	if (!(STK_COMP((uintptr_t)cache_frame_p, stack_end)
+	      && STK_COMP(stack_start, (uintptr_t)cache_frame_p)))
+	  break;
+	cache_had_name = name && (last || !SCHEME_NULLP(name));
+      } else {
+	cache_frame_p = NULL;
+	cache_had_name = 0;
+      }
+    }
+#endif
+
     if (name && !SCHEME_NULLP(name)) { /* null is used to help unwind without a true name */
       name = scheme_make_pair(name, scheme_null);
       if (last)
@@ -433,16 +447,17 @@ Scheme_Object *scheme_native_stack_trace(void)
        might not be used (depending on how the C compiler optimized the
        code); any frame whose procedure has a name is JITted code, so
        it will use the return address from the stack. */
-    if (STK_COMP((uintptr_t)halfway, (uintptr_t)prev_frame_p)
-	&& prev_had_name) {
-      set_cache(prev_frame_p, last);
+    if (STK_COMP((uintptr_t)halfway, (uintptr_t)cache_frame_p)
+	&& cache_had_name) {
+      set_cache(cache_frame_p, last);
       if (!added_list_elem)
 	shift_cache_to_next = 1;
       halfway = stack_end;
-      unsuccess = -100000; /* if we got halfway, no need to bail out later */
+      unsuccess = -8 * UNKNOWN_FRAME_LIMIT; /* if we got halfway, less likely to bail out later */
     }
 
-    prev_had_name = !!name;
+    if (!use_unw)
+      cache_had_name = !!name;
     
 #ifdef MZ_USE_DWARF_LIBUNWIND
     if (use_unw) {
@@ -453,7 +468,6 @@ Scheme_Object *scheme_native_stack_trace(void)
 	if (!(STK_COMP((uintptr_t)pp, stack_end)
 	      && STK_COMP(stack_start, (uintptr_t)pp)))
 	  break;
-	prev_frame_p = pp;
 # ifdef MZ_USE_JIT_ARM
         stack_addr = (unw_word_t)&(pp[JIT_NEXT_FP_OFFSET+2]);
 	unw_manual_step(&c, 
@@ -468,7 +482,6 @@ Scheme_Object *scheme_native_stack_trace(void)
 # endif
 	manual_unw = 0;
       } else {
-	prev_frame_p = NULL;
         unw_step(&c);
         q = (void *)unw_get_ip(&c);
         if (unw_reset_bad_ptr_flag(&c))
@@ -482,12 +495,12 @@ Scheme_Object *scheme_native_stack_trace(void)
       if (STK_COMP((uintptr_t)q, (uintptr_t)p))
         break;
       p = q;
-      prev_frame_p = p;
+      cache_frame_p = p;
     }
   }
 
   if (shift_cache_to_next)
-    stack_cache_stack[stack_cache_stack_pos].cache = scheme_null;
+    stack_cache_stack[stack_cache_stack_pos].cache = tail;
 
 #ifdef MZ_USE_DWARF_LIBUNWIND
   unw_destroy_local(&c);