diff --git a/core/gc.c b/core/gc.c
index 3d71d430..890bbf2c 100644
--- a/core/gc.c
+++ b/core/gc.c
@@ -145,8 +145,8 @@ void gst_mark(Gst *vm, GstValueUnion x, GstType type) {
                 gc_header(thread->data)->color = vm->black;
                 while (frame <= end)
                     frame = gst_mark_stackframe(vm, frame);
-                if (x.thread->parent)
-                    gst_mark_value(vm, gst_wrap_thread(x.thread->parent));
+                if (thread->parent)
+                    gst_mark_value(vm, gst_wrap_thread(thread->parent));
             }
             break;
 
diff --git a/core/parse.c b/core/parse.c
index 6ed40d03..ef4c5990 100644
--- a/core/parse.c
+++ b/core/parse.c
@@ -62,7 +62,7 @@ static GstParseState *parser_peek(GstParser *p) {
     if (!p->count) {
         return NULL;
     }
-    return p->data + p->count - 1;
+    return p->data + (p->count - 1);
 }
 
 /* Remove the top state from the ParseStack */
@@ -88,8 +88,9 @@ static GstValue quote(GstParser *p, GstValue x) {
 static void parser_push(GstParser *p, ParseType type, uint8_t character) {
     GstParseState *top;
     if (p->count >= p->cap) {
-        uint32_t newCap = 2 * p->count;
-        GstParseState *data = gst_alloc(p->vm, newCap);
+        uint32_t newCap = 2 * p->count + 2;
+        GstParseState *data = gst_alloc(p->vm, newCap * sizeof(GstParseState));
+        gst_memcpy(data, p->data, p->cap * sizeof(GstParseState));
         p->data = data;
         p->cap = newCap;
     }
diff --git a/core/thread.c b/core/thread.c
index ada5f96d..ee572c0b 100644
--- a/core/thread.c
+++ b/core/thread.c
@@ -32,7 +32,6 @@ GstThread *gst_thread(Gst *vm, GstValue callee, uint32_t capacity) {
     thread->count = GST_FRAME_SIZE;
     thread->data = data;
     thread->status = GST_THREAD_PENDING;
-    thread->retindex = 0;
     stack = data + GST_FRAME_SIZE;
     gst_frame_size(stack) = 0;
     gst_frame_prevsize(stack) = 0;
diff --git a/core/vm.c b/core/vm.c
index eba8c37b..81ffd4f3 100644
--- a/core/vm.c
+++ b/core/vm.c
@@ -398,6 +398,7 @@ int gst_continue(Gst *vm) {
                 }
             }
             stack = vm->thread->data + vm->thread->count;
+            stack[gst_frame_ret(stack)] = vm->ret;
             pc = gst_frame_pc(stack);
             continue;
 
diff --git a/include/gst/gst.h b/include/gst/gst.h
index 9fbdea14..93c77df8 100644
--- a/include/gst/gst.h
+++ b/include/gst/gst.h
@@ -204,7 +204,6 @@ struct GstValue {
 struct GstThread {
     uint32_t count;
     uint32_t capacity;
-    uint32_t retindex;
     GstValue *data;
     GstThread *parent;
     enum {
diff --git a/libs/repl.gst b/libs/repl.gst
index 16a1748a..229107ac 100644
--- a/libs/repl.gst
+++ b/libs/repl.gst
@@ -1,8 +1,5 @@
 (namespace-set! "gst.repl")
 
-"Hold all compile time evaluators"
-(export! "evaluators" {})
-
 "Read a line"
 (export! "readline" (fn []
     (: b (buffer))
@@ -16,14 +13,15 @@
 "Create a parser"
 (export! "p" (parser))
 
-"Run a simple repl. Does not handle errors and other
-such details."
+"Run a simple repl."
 (while 1
-    (: t (thread (fn []
-        (write stdout ">> ")
-        (: line (readline))
+    (write stdout ">> ")
+    (: t (thread (fn [line]
+        (: ret 1)
         (while line
             (: line (parse-charseq p line))
             (if (parse-hasvalue p)
-                ((compile (parse-consume p))))))))
-    (transfer t))
+                (: ret ((compile (parse-consume p))))))
+        ret)))
+    (: res (tran t (readline)))
+    (if (= (status t) "dead") (print res) (print "Error: " res)))