diff --git a/src/comp/middle/typeck.rs b/src/comp/middle/typeck.rs
index 1ec4fe2531a..ca8c26fe94f 100644
--- a/src/comp/middle/typeck.rs
+++ b/src/comp/middle/typeck.rs
@@ -18,11 +18,11 @@ import std.option.some;
 
 type ty_table = hashmap[ast.def_id, @ty];
 type crate_ctxt = rec(session.session sess,
-                      @ty_table item_types,
-                      mutable int next_var_id);
+                      @ty_table item_types);
 
 type fn_ctxt = rec(@ty ret_ty,
                    @ty_table locals,
+                   mutable int next_var_id,
                    @crate_ctxt ccx);
 
 type arg = rec(ast.mode mode, @ty ty);
@@ -1695,8 +1695,8 @@ fn check_expr(&fn_ctxt fcx, @ast.expr expr) -> @ast.expr {
 }
 
 fn next_ty_var(&fn_ctxt fcx) -> @ty {
-    auto t = plain_ty(ty_var(fcx.ccx.next_var_id));
-    fcx.ccx.next_var_id += 1;
+    auto t = plain_ty(ty_var(fcx.next_var_id));
+    fcx.next_var_id += 1;
     ret t;
 }
 
@@ -1814,6 +1814,7 @@ fn check_const(&@crate_ctxt ccx, &span sp, ast.ident ident, @ast.ty t,
     auto rty = ann_to_type(ann);
     let fn_ctxt fcx = rec(ret_ty = rty,
                           locals = @common.new_def_hash[@ty](),
+                          mutable next_var_id = 0,
                           ccx = ccx);
     auto e_ = check_expr(fcx, e);
     // FIXME: necessary? Correct sequence?
@@ -1845,6 +1846,7 @@ fn check_fn(&@crate_ctxt ccx, &span sp, ast.ident ident, &ast._fn f,
 
     let fn_ctxt fcx = rec(ret_ty = output_ty,
                           locals = local_ty_table,
+                          mutable next_var_id = 0,
                           ccx = ccx);
 
     // TODO: Make sure the type of the block agrees with the function type.
@@ -1861,8 +1863,7 @@ fn check_crate(session.session sess, @ast.crate crate) -> @ast.crate {
     auto result = collect_item_types(crate);
 
     auto ccx = @rec(sess=sess,
-                    item_types=result._1,
-                    mutable next_var_id=0);
+                    item_types=result._1);
 
     auto fld = fold.new_identity_fold[@crate_ctxt]();
     auto f = check_fn;  // FIXME: trans_const_lval bug