diff --git a/include/chibi/sexp.h b/include/chibi/sexp.h
index 200191d0..a870084c 100755
--- a/include/chibi/sexp.h
+++ b/include/chibi/sexp.h
@@ -233,7 +233,7 @@ struct sexp_type_struct {
   unsigned short size_scale;
   short weak_base, weak_len_base, weak_len_off, weak_len_scale, weak_len_extra;
   short depth;
-  sexp name, cpl, slots;
+  sexp name, cpl, slots, dl;
   sexp_proc2 finalize;
   sexp_proc3 print;
 };
@@ -992,6 +992,7 @@ SEXP_API sexp_heap sexp_global_heap;
 #define sexp_type_slots(x)             (sexp_field(x, type, SEXP_TYPE, slots))
 #define sexp_type_finalize(x)          (sexp_field(x, type, SEXP_TYPE, finalize))
 #define sexp_type_print(x)             (sexp_field(x, type, SEXP_TYPE, print))
+#define sexp_type_dl(x)                (sexp_field(x, type, SEXP_TYPE, dl))
 
 #define sexp_bignum_sign(x)            (sexp_field(x, bignum, SEXP_BIGNUM, sign))
 #define sexp_bignum_length(x)          (sexp_field(x, bignum, SEXP_BIGNUM, length))
diff --git a/sexp.c b/sexp.c
index 146f51d2..179b4f39 100644
--- a/sexp.c
+++ b/sexp.c
@@ -120,53 +120,53 @@ sexp sexp_finalize_dl (sexp ctx sexp_api_params(self, n), sexp dl) {
 #endif
 
 static struct sexp_type_struct _sexp_type_specs[] = {
-  {SEXP_OBJECT, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Object", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_TYPE, sexp_offsetof(type, name), 3, 3, 0, 0, sexp_sizeof(type), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Type", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_FIXNUM, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Integer", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_NUMBER, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Number", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_CHAR, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Char", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_BOOLEAN, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Boolean", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_PAIR, sexp_offsetof(pair, car), 2, 3, 0, 0, sexp_sizeof(pair), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Pair", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_SYMBOL, 0, 0, 0, 0, 0, sexp_sizeof(symbol)+1, sexp_offsetof(symbol, length), 1, 0, 0, 0, 0, 0, 0, (sexp)"Symbol", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_BYTES, 0, 0, 0, 0, 0, sexp_sizeof(bytes)+1, sexp_offsetof(bytes, length), 1, 0, 0, 0, 0, 0, 0, (sexp)"Byte-Vector", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
+  {SEXP_OBJECT, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Object", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_TYPE, sexp_offsetof(type, name), 3+SEXP_USE_DL, 3+SEXP_USE_DL, 0, 0, sexp_sizeof(type), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Type", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_FIXNUM, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Integer", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_NUMBER, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Number", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_CHAR, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Char", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_BOOLEAN, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Boolean", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_PAIR, sexp_offsetof(pair, car), 2, 3, 0, 0, sexp_sizeof(pair), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Pair", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_SYMBOL, 0, 0, 0, 0, 0, sexp_sizeof(symbol)+1, sexp_offsetof(symbol, length), 1, 0, 0, 0, 0, 0, 0, (sexp)"Symbol", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_BYTES, 0, 0, 0, 0, 0, sexp_sizeof(bytes)+1, sexp_offsetof(bytes, length), 1, 0, 0, 0, 0, 0, 0, (sexp)"Byte-Vector", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
 #if SEXP_USE_PACKED_STRINGS
-  {SEXP_STRING, 0, 0, 0, 0, 0, sexp_sizeof(string)+1, sexp_offsetof(string, length), 1, 0, 0, 0, 0, 0, 0, (sexp)"String", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
+  {SEXP_STRING, 0, 0, 0, 0, 0, sexp_sizeof(string)+1, sexp_offsetof(string, length), 1, 0, 0, 0, 0, 0, 0, (sexp)"String", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
 #else
-  {SEXP_STRING, sexp_offsetof(string, bytes), 1, 1, 0, 0, sexp_sizeof(string), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"String", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
+  {SEXP_STRING, sexp_offsetof(string, bytes), 1, 1, 0, 0, sexp_sizeof(string), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"String", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
 #endif
-  {SEXP_VECTOR, sexp_offsetof(vector, data), 0, 0, sexp_offsetof(vector, length), 1, sexp_sizeof(vector), sexp_offsetof(vector, length), sizeof(sexp), 0, 0, 0, 0, 0, 0, (sexp)"Vector", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_FLONUM, 0, 0, 0, 0, 0, sexp_sizeof(flonum), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Flonum", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_BIGNUM, 0, 0, 0, 0, 0, sexp_sizeof(bignum), sexp_offsetof(bignum, length), sizeof(sexp_uint_t), 0, 0, 0, 0, 0, 0, (sexp)"Bignum", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
+  {SEXP_VECTOR, sexp_offsetof(vector, data), 0, 0, sexp_offsetof(vector, length), 1, sexp_sizeof(vector), sexp_offsetof(vector, length), sizeof(sexp), 0, 0, 0, 0, 0, 0, (sexp)"Vector", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_FLONUM, 0, 0, 0, 0, 0, sexp_sizeof(flonum), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Flonum", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_BIGNUM, 0, 0, 0, 0, 0, sexp_sizeof(bignum), sexp_offsetof(bignum, length), sizeof(sexp_uint_t), 0, 0, 0, 0, 0, 0, (sexp)"Bignum", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
 #if SEXP_USE_RATIOS
-  {SEXP_RATIO, sexp_offsetof(ratio, numerator), 2, 2, 0, 0, sexp_sizeof(ratio), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Ratio", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
+  {SEXP_RATIO, sexp_offsetof(ratio, numerator), 2, 2, 0, 0, sexp_sizeof(ratio), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Ratio", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
 #endif
 #if SEXP_USE_COMPLEX
-  {SEXP_COMPLEX, sexp_offsetof(complex, real), 2, 2, 0, 0, sexp_sizeof(complex), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Complex", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
+  {SEXP_COMPLEX, sexp_offsetof(complex, real), 2, 2, 0, 0, sexp_sizeof(complex), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Complex", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
 #endif
-  {SEXP_IPORT, sexp_offsetof(port, name), 2, 2, 0, 0, sexp_sizeof(port), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Input-Port", SEXP_FALSE, SEXP_FALSE, SEXP_FINALIZE_PORT, NULL},
-  {SEXP_OPORT, sexp_offsetof(port, name), 2, 2, 0, 0, sexp_sizeof(port), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Output-Port", SEXP_FALSE, SEXP_FALSE, SEXP_FINALIZE_PORT, NULL},
-  {SEXP_EXCEPTION, sexp_offsetof(exception, kind), 6, 6, 0, 0, sexp_sizeof(exception), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Exception", SEXP_FALSE, SEXP_FALSE, NULL, (sexp_proc3)sexp_write_simple_object},
-  {SEXP_PROCEDURE, sexp_offsetof(procedure, bc), 2, 2, 0, 0, sexp_sizeof(procedure), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Procedure", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_MACRO, sexp_offsetof(macro, proc), 3, 3, 0, 0, sexp_sizeof(macro), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Macro", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_SYNCLO, sexp_offsetof(synclo, env), 3, 3, 0, 0, sexp_sizeof(synclo), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Syntactic-Closure", SEXP_FALSE, SEXP_FALSE, NULL, (sexp_proc3)sexp_write_simple_object},
-  {SEXP_ENV, sexp_offsetof(env, parent), 3+SEXP_USE_RENAME_BINDINGS, 3+SEXP_USE_RENAME_BINDINGS, 0, 0, sexp_sizeof(env), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Environment", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_BYTECODE, sexp_offsetof(bytecode, name), 3, 3, 0, 0, sexp_sizeof(bytecode), offsetof(struct sexp_struct, value.bytecode.length), 1, 0, 0, 0, 0, 0, 0, (sexp)"Bytecode", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_CORE, sexp_offsetof(core, name), 1, 1, 0, 0, sexp_sizeof(core), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Core-Form", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
+  {SEXP_IPORT, sexp_offsetof(port, name), 2, 2, 0, 0, sexp_sizeof(port), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Input-Port", SEXP_FALSE, SEXP_FALSE, NULL, SEXP_FINALIZE_PORT, NULL},
+  {SEXP_OPORT, sexp_offsetof(port, name), 2, 2, 0, 0, sexp_sizeof(port), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Output-Port", SEXP_FALSE, SEXP_FALSE, NULL, SEXP_FINALIZE_PORT, NULL},
+  {SEXP_EXCEPTION, sexp_offsetof(exception, kind), 6, 6, 0, 0, sexp_sizeof(exception), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Exception", SEXP_FALSE, SEXP_FALSE, NULL, NULL, (sexp_proc3)sexp_write_simple_object},
+  {SEXP_PROCEDURE, sexp_offsetof(procedure, bc), 2, 2, 0, 0, sexp_sizeof(procedure), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Procedure", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_MACRO, sexp_offsetof(macro, proc), 3, 3, 0, 0, sexp_sizeof(macro), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Macro", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_SYNCLO, sexp_offsetof(synclo, env), 3, 3, 0, 0, sexp_sizeof(synclo), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Syntactic-Closure", SEXP_FALSE, SEXP_FALSE, NULL, NULL, (sexp_proc3)sexp_write_simple_object},
+  {SEXP_ENV, sexp_offsetof(env, parent), 3+SEXP_USE_RENAME_BINDINGS, 3+SEXP_USE_RENAME_BINDINGS, 0, 0, sexp_sizeof(env), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Environment", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_BYTECODE, sexp_offsetof(bytecode, name), 3, 3, 0, 0, sexp_sizeof(bytecode), offsetof(struct sexp_struct, value.bytecode.length), 1, 0, 0, 0, 0, 0, 0, (sexp)"Bytecode", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_CORE, sexp_offsetof(core, name), 1, 1, 0, 0, sexp_sizeof(core), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Core-Form", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
 #if SEXP_USE_DL
-  {SEXP_DL, sexp_offsetof(dl, file), 1, 1, 0, 0, sexp_sizeof(dl), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Dynamic-Library", SEXP_FALSE, SEXP_FALSE, sexp_finalize_dl, NULL},
+  {SEXP_DL, sexp_offsetof(dl, file), 1, 1, 0, 0, sexp_sizeof(dl), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Dynamic-Library", SEXP_FALSE, SEXP_FALSE, NULL, sexp_finalize_dl, NULL},
 #endif
-  {SEXP_OPCODE, sexp_offsetof(opcode, name), 8+SEXP_USE_DL, 8+SEXP_USE_DL, 0, 0, sexp_sizeof(opcode), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Opcode", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_LAMBDA, sexp_offsetof(lambda, name), 11, 11, 0, 0, sexp_sizeof(lambda), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Lambda", SEXP_FALSE, SEXP_FALSE, NULL, (sexp_proc3)sexp_write_simple_object},
-  {SEXP_CND, sexp_offsetof(cnd, test), 4, 4, 0, 0, sexp_sizeof(cnd), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Conditional", SEXP_FALSE, SEXP_FALSE, NULL, (sexp_proc3)sexp_write_simple_object},
-  {SEXP_REF, sexp_offsetof(ref, name), 3, 3, 0, 0, sexp_sizeof(ref), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Reference", SEXP_FALSE, SEXP_FALSE, NULL, (sexp_proc3)sexp_write_simple_object},
-  {SEXP_SET, sexp_offsetof(set, var), 3, 3, 0, 0, sexp_sizeof(set), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Set!", SEXP_FALSE, SEXP_FALSE, NULL, (sexp_proc3)sexp_write_simple_object},
-  {SEXP_SEQ, sexp_offsetof(seq, ls), 2, 2, 0, 0, sexp_sizeof(seq), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Sequence", SEXP_FALSE, SEXP_FALSE, NULL, (sexp_proc3)sexp_write_simple_object},
-  {SEXP_LIT, sexp_offsetof(lit, value), 2, 2, 0, 0, sexp_sizeof(lit), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Literal", SEXP_FALSE, SEXP_FALSE, NULL, (sexp_proc3)sexp_write_simple_object},
-  {SEXP_STACK, sexp_offsetof(stack, data), 1, 1, sexp_offsetof(stack, top), 1, sexp_sizeof(stack), offsetof(struct sexp_struct, value.stack.length), sizeof(sexp), 0, 0, 0, 0, 0, 0, (sexp)"Stack", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_CONTEXT, sexp_offsetof(context, bc), 13+SEXP_USE_DL, 13+SEXP_USE_DL, 0, 0, sexp_sizeof(context), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Context", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
-  {SEXP_CPOINTER, sexp_offsetof(cpointer, parent), 1, 0, 0, 0, sexp_sizeof(cpointer), sexp_offsetof(cpointer, length), 1, 0, 0, 0, 0, 0, 0, (sexp)"Cpointer", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
+  {SEXP_OPCODE, sexp_offsetof(opcode, name), 8+SEXP_USE_DL, 8+SEXP_USE_DL, 0, 0, sexp_sizeof(opcode), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Opcode", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_LAMBDA, sexp_offsetof(lambda, name), 11, 11, 0, 0, sexp_sizeof(lambda), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Lambda", SEXP_FALSE, SEXP_FALSE, NULL, NULL, (sexp_proc3)sexp_write_simple_object},
+  {SEXP_CND, sexp_offsetof(cnd, test), 4, 4, 0, 0, sexp_sizeof(cnd), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Conditional", SEXP_FALSE, SEXP_FALSE, NULL, NULL, (sexp_proc3)sexp_write_simple_object},
+  {SEXP_REF, sexp_offsetof(ref, name), 3, 3, 0, 0, sexp_sizeof(ref), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Reference", SEXP_FALSE, SEXP_FALSE, NULL, NULL, (sexp_proc3)sexp_write_simple_object},
+  {SEXP_SET, sexp_offsetof(set, var), 3, 3, 0, 0, sexp_sizeof(set), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Set!", SEXP_FALSE, SEXP_FALSE, NULL, NULL, (sexp_proc3)sexp_write_simple_object},
+  {SEXP_SEQ, sexp_offsetof(seq, ls), 2, 2, 0, 0, sexp_sizeof(seq), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Sequence", SEXP_FALSE, SEXP_FALSE, NULL, NULL, (sexp_proc3)sexp_write_simple_object},
+  {SEXP_LIT, sexp_offsetof(lit, value), 2, 2, 0, 0, sexp_sizeof(lit), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Literal", SEXP_FALSE, SEXP_FALSE, NULL, NULL, (sexp_proc3)sexp_write_simple_object},
+  {SEXP_STACK, sexp_offsetof(stack, data), 1, 1, sexp_offsetof(stack, top), 1, sexp_sizeof(stack), offsetof(struct sexp_struct, value.stack.length), sizeof(sexp), 0, 0, 0, 0, 0, 0, (sexp)"Stack", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_CONTEXT, sexp_offsetof(context, bc), 13+SEXP_USE_DL, 13+SEXP_USE_DL, 0, 0, sexp_sizeof(context), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Context", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
+  {SEXP_CPOINTER, sexp_offsetof(cpointer, parent), 1, 0, 0, 0, sexp_sizeof(cpointer), sexp_offsetof(cpointer, length), 1, 0, 0, 0, 0, 0, 0, (sexp)"Cpointer", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
 #if SEXP_USE_AUTO_FORCE
-  {SEXP_PROMISE, sexp_offsetof(promise, thunk), 2, 2, 0, 0, sexp_sizeof(promise), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Promise", SEXP_FALSE, SEXP_FALSE, NULL, NULL},
+  {SEXP_PROMISE, sexp_offsetof(promise, thunk), 2, 2, 0, 0, sexp_sizeof(promise), 0, 0, 0, 0, 0, 0, 0, 0, (sexp)"Promise", SEXP_FALSE, SEXP_FALSE, NULL, NULL, NULL},
 #endif
 };
 
@@ -222,9 +222,9 @@ sexp sexp_register_type_op (sexp ctx sexp_api_params(self, n), sexp name,
       sexp_type_weak_len_off(type) = sexp_unbox_fixnum(wo);
       sexp_type_weak_len_scale(type) = sexp_unbox_fixnum(ws);
       sexp_type_weak_len_extra(type) = sexp_unbox_fixnum(we);
-      /* sexp_type_name(type) = strdup(sexp_string_data(name)); */
       sexp_type_name(type) = name;
       sexp_type_finalize(type) = f;
+      if (f) sexp_type_dl(type) = sexp_context_dl(ctx);
       sexp_type_print(type) = p;
       if (sexp_typep(parent)) {
         len = sexp_vectorp(sexp_type_cpl(parent)) ? sexp_vector_length(sexp_type_cpl(parent)) : 1;
@@ -406,7 +406,7 @@ void sexp_destroy_context (sexp ctx) {
     heap = sexp_context_heap(ctx);
     sexp_markedp(ctx) = 1;
     sexp_markedp(sexp_context_globals(ctx)) = 1;
-    sexp_markedp(sexp_global(ctx, SEXP_G_TYPES)) = 1;
+    sexp_mark(ctx, sexp_global(ctx, SEXP_G_TYPES));
     sexp_sweep(ctx, &sum_freed); /* sweep w/o mark to run finalizers */
     sexp_context_heap(ctx) = NULL;
     for ( ; heap; heap=tmp) {