diff --git a/compile.c b/compile.c
index 1c0309ac8502aa..901fcb15c8d090 100644
--- a/compile.c
+++ b/compile.c
@@ -1560,15 +1560,22 @@ iseq_set_sequence(rb_iseq_t *iseq, LINK_ANCHOR *anchor)
 			}
 		      case TS_CDHASH:
 			{
+			    int i;
 			    VALUE map = operands[j];
 			    struct cdhash_set_label_struct data;
-                            data.hash = map;
-                            data.pos = pos;
-                            data.len = len;
-			    rb_hash_foreach(map, cdhash_set_label_i, (VALUE)&data);
+			    data.hash = map;
+			    data.pos = pos;
+			    data.len = len;
+			    if (RB_TYPE_P(map, T_ARRAY)) {
+				data.hash = rb_hash_new();
+				for (i=0; i<RARRAY_LEN(map); i+=2)
+				    cdhash_set_label_i(RARRAY_AREF(map, i), RARRAY_AREF(map, i+1), &data);
+			    } else {
+				rb_hash_foreach(map, cdhash_set_label_i, (VALUE)&data);
+			    }
 
-			    hide_obj(map);
-			    generated_iseq[pos + 1 + j] = map;
+			    hide_obj(data.hash);
+			    generated_iseq[pos + 1 + j] = data.hash;
 			    break;
 			}
 		      case TS_LINDEX:
diff --git a/iseq.c b/iseq.c
index 700a161f6bc3e6..a5823f629daaba 100644
--- a/iseq.c
+++ b/iseq.c
@@ -1718,7 +1718,12 @@ iseq_data_to_ary(rb_iseq_t *iseq)
     for (i=0; i<iseq->local_table_size; i++) {
 	ID lid = iseq->local_table[i];
 	if (lid) {
-	    if (rb_id2str(lid)) rb_ary_push(locals, ID2SYM(lid));
+	    if (rb_id2str(lid)) {
+		rb_ary_push(locals, ID2SYM(lid));
+	    }
+	    else { /* hidden variable from id_internal() */
+		rb_ary_push(locals, ULONG2NUM(iseq->local_table_size-i+1));
+	    }
 	}
 	else {
 	    rb_ary_push(locals, ID2SYM(rb_intern("#arg_rest")));
diff --git a/load.c b/load.c
index e5014c165faef0..4f753f2c521b92 100644
--- a/load.c
+++ b/load.c
@@ -9,6 +9,8 @@
 #include "eval_intern.h"
 #include "probes.h"
 #include "node.h"
+#include "iseq.h"
+#include "vm_debug.h"
 
 VALUE ruby_dln_librefs;
 
@@ -606,12 +608,25 @@ rb_load_internal0(rb_thread_t *th, VALUE fname, int wrap)
     if (state == 0) {
 	NODE *node;
 	VALUE iseq;
-
-	th->mild_compile_error++;
-	node = (NODE *)rb_load_file_str(fname);
-	loaded = TRUE;
-	iseq = rb_iseq_new_top(node, rb_str_new2("<top (required)>"), fname, rb_realpath_internal(Qnil, fname, 1), Qfalse);
-	th->mild_compile_error--;
+	VALUE io;
+	VALUE fcname = rb_str_plus(fname, rb_str_new2("o"));
+
+	if (RTEST(rb_funcall(rb_cFile, rb_intern("exist?"), 1, fcname))) {
+	    dpv("loading bytecode from", fcname);
+	    iseq = rb_iseq_load(rb_marshal_load(rb_funcall(rb_cIO, rb_intern("binread"), 1, fcname)), Qnil, Qnil);
+	    loaded = TRUE;
+	} else {
+	    th->mild_compile_error++;
+	    node = (NODE *)rb_load_file_str(fname);
+	    loaded = TRUE;
+	    iseq = rb_iseq_new_top(node, rb_str_new2("<top (required)>"), fname, rb_realpath_internal(Qnil, fname, 1), Qfalse);
+	    th->mild_compile_error--;
+
+	    io = rb_file_open_str(fcname, "w");
+	    rb_marshal_dump(rb_funcall(iseq, rb_intern("to_a"), 0), io);
+	    rb_io_close(io);
+	    dpv("wrote bytecode to", fcname);
+	}
 	rb_iseq_eval(iseq);
     }
     POP_TAG();