diff --git a/src/cmd/compile/internal/ir/type.go b/src/cmd/compile/internal/ir/type.go
index f8aa35da4c..d810a6d60d 100644
--- a/src/cmd/compile/internal/ir/type.go
+++ b/src/cmd/compile/internal/ir/type.go
@@ -93,8 +93,8 @@ type Field struct {
 	Decl     *Name
 }
 
-func NewField(pos src.XPos, sym *types.Sym, ntyp Ntype, typ *types.Type) *Field {
-	return &Field{Pos: pos, Sym: sym, Ntype: ntyp, Type: typ}
+func NewField(pos src.XPos, sym *types.Sym, typ *types.Type) *Field {
+	return &Field{Pos: pos, Sym: sym, Ntype: nil, Type: typ}
 }
 
 func (f *Field) String() string {
diff --git a/src/cmd/compile/internal/reflectdata/alg.go b/src/cmd/compile/internal/reflectdata/alg.go
index de23387ca1..0ed3eb2875 100644
--- a/src/cmd/compile/internal/reflectdata/alg.go
+++ b/src/cmd/compile/internal/reflectdata/alg.go
@@ -129,10 +129,10 @@ func genhash(t *types.Type) *obj.LSym {
 
 	// func sym(p *T, h uintptr) uintptr
 	args := []*ir.Field{
-		ir.NewField(base.Pos, typecheck.Lookup("p"), nil, types.NewPtr(t)),
-		ir.NewField(base.Pos, typecheck.Lookup("h"), nil, types.Types[types.TUINTPTR]),
+		ir.NewField(base.Pos, typecheck.Lookup("p"), types.NewPtr(t)),
+		ir.NewField(base.Pos, typecheck.Lookup("h"), types.Types[types.TUINTPTR]),
 	}
-	results := []*ir.Field{ir.NewField(base.Pos, nil, nil, types.Types[types.TUINTPTR])}
+	results := []*ir.Field{ir.NewField(base.Pos, nil, types.Types[types.TUINTPTR])}
 	tfn := ir.NewFuncType(base.Pos, nil, args, results)
 
 	fn := typecheck.DeclFunc(sym, tfn)
@@ -359,8 +359,8 @@ func geneq(t *types.Type) *obj.LSym {
 
 	// func sym(p, q *T) bool
 	tfn := ir.NewFuncType(base.Pos, nil,
-		[]*ir.Field{ir.NewField(base.Pos, typecheck.Lookup("p"), nil, types.NewPtr(t)), ir.NewField(base.Pos, typecheck.Lookup("q"), nil, types.NewPtr(t))},
-		[]*ir.Field{ir.NewField(base.Pos, typecheck.Lookup("r"), nil, types.Types[types.TBOOL])})
+		[]*ir.Field{ir.NewField(base.Pos, typecheck.Lookup("p"), types.NewPtr(t)), ir.NewField(base.Pos, typecheck.Lookup("q"), types.NewPtr(t))},
+		[]*ir.Field{ir.NewField(base.Pos, typecheck.Lookup("r"), types.Types[types.TBOOL])})
 
 	fn := typecheck.DeclFunc(sym, tfn)
 	np := ir.AsNode(tfn.Type().Params().Field(0).Nname)
diff --git a/src/cmd/compile/internal/reflectdata/reflect.go b/src/cmd/compile/internal/reflectdata/reflect.go
index d6e6b115a4..1804eaefe6 100644
--- a/src/cmd/compile/internal/reflectdata/reflect.go
+++ b/src/cmd/compile/internal/reflectdata/reflect.go
@@ -1856,7 +1856,7 @@ func methodWrapper(rcvr *types.Type, method *types.Field, forItab bool) *obj.LSy
 	typecheck.DeclContext = ir.PEXTERN
 
 	tfn := ir.NewFuncType(base.Pos,
-		ir.NewField(base.Pos, typecheck.Lookup(".this"), nil, rcvr),
+		ir.NewField(base.Pos, typecheck.Lookup(".this"), rcvr),
 		typecheck.NewFuncParams(method.Type.Params(), true),
 		typecheck.NewFuncParams(method.Type.Results(), false))
 
diff --git a/src/cmd/compile/internal/typecheck/subr.go b/src/cmd/compile/internal/typecheck/subr.go
index af16e826bd..8cd81cf12b 100644
--- a/src/cmd/compile/internal/typecheck/subr.go
+++ b/src/cmd/compile/internal/typecheck/subr.go
@@ -40,7 +40,7 @@ func NewFuncParams(tl *types.Type, mustname bool) []*ir.Field {
 			// TODO(mdempsky): Preserve original position, name, and package.
 			s = Lookup(s.Name)
 		}
-		a := ir.NewField(base.Pos, s, nil, t.Type)
+		a := ir.NewField(base.Pos, s, t.Type)
 		a.Pos = t.Pos
 		a.IsDDD = t.IsDDD()
 		args = append(args, a)