diff --git a/interp.c b/interp.c
index 18d90e5..13e3a35 100644
--- a/interp.c
+++ b/interp.c
@@ -328,21 +328,27 @@ break_for_loop:
 
 static void perform_tail_call(interp_state_t *state)
 {
-  value_t new_lambda, new_argv, new_ctx, new_k;
+  gc_root_t new_lambda, new_argv, new_ctx, new_k;
 
-  new_lambda = get_input(state, get_fixnum(_LAMBDA_SLOT(state->lambda.value, TAIL_CALL)));
-  new_argv   = get_input(state, get_fixnum(_LAMBDA_SLOT(state->lambda.value, ARG_LIST)));
-  new_ctx    = get_input(state, get_fixnum(_LAMBDA_SLOT(state->lambda.value, CONTEXT)));
-  new_k      = get_input(state, get_fixnum(_LAMBDA_SLOT(state->lambda.value, CONTINUATION)));
+  register_gc_root(&new_lambda, get_input(state, get_fixnum(_LAMBDA_SLOT(state->lambda.value, TAIL_CALL))));
+  register_gc_root(&new_argv,   get_input(state, get_fixnum(_LAMBDA_SLOT(state->lambda.value, ARG_LIST))));
+  register_gc_root(&new_ctx,    get_input(state, get_fixnum(_LAMBDA_SLOT(state->lambda.value, CONTEXT))));
+  register_gc_root(&new_k,      get_input(state, get_fixnum(_LAMBDA_SLOT(state->lambda.value, CONTINUATION))));
 
-  /* If new lambda or continuation is a template, instantiate it here. */
-  new_lambda = make_lambda(state, new_lambda);
-  new_k      = make_lambda(state, new_k);
+  /* If new lambda or continuation is a template, instantiate it here */
+  new_lambda.value    = make_lambda(state, new_lambda.value);
+  new_k.value         = make_lambda(state, new_k.value);
 
-  state->lambda.value = new_lambda;
-  state->argv.value   = new_argv;
-  state->ctx.value    = new_ctx;
-  state->k.value      = new_k;
+  /* Transfer control to new function */
+  state->lambda.value = new_lambda.value;
+  state->argv.value   = new_argv.value;
+  state->ctx.value    = new_ctx.value;
+  state->k.value      = new_k.value;
+
+  unregister_gc_root(&new_lambda);
+  unregister_gc_root(&new_argv);
+  unregister_gc_root(&new_ctx);
+  unregister_gc_root(&new_k);
 }
 
 static value_t eval_expression(interp_state_t *state, uint8_t code, uint8_t in1, uint8_t in2)
diff --git a/src/examples/factorial.rla b/src/examples/factorial.rla
index ff28eb1..80b296d 100755
--- a/src/examples/factorial.rla
+++ b/src/examples/factorial.rla
@@ -10,6 +10,7 @@
   ;       (lambda () (string->number number-string))
   ;       (lambda (n) (k (fact n))))))
   #(
+    #="string->number"
     #S(#="template"
       ; (let/cc k
       ;   (lambda (n)
@@ -25,14 +26,13 @@
       0x40  ; i0
       0x41  ; i1
     )
-    #="string->number"  ; g2
   )
   #()
-  1
-  "\x00\x80\x1b\x01"; (set! f0 (lambda g1))
-  0x02  ; g2
+  0
+  ""
+  0x01  ; g1
   0xfd  ; argv
   0xfe  ; ctx
-  0x80  ; f0
+  0x02  ; g2
 )
 ; vim:set syntax= sw=2 expandtab:
diff --git a/src/lib/math/fact.rla b/src/lib/math/fact.rla
index fbea33c..322aa88 100755
--- a/src/lib/math/fact.rla
+++ b/src/lib/math/fact.rla
@@ -50,7 +50,7 @@
         #=0  ; fact
       )
       "\x80"
-      2
+      1
       "\x09\x80\x40\x01\; (set! f0 (fix- i0 g1))
        \x02\x80\x80\x00"; (set! f0 (cons f0 nil))
       0x03  ; g3