diff --git a/cl/classfile.go b/cl/classfile.go
index 6f09e2379..e0c7579c8 100644
--- a/cl/classfile.go
+++ b/cl/classfile.go
@@ -22,6 +22,7 @@ import (
 	"go/types"
 	"log"
 	"path/filepath"
+	"strconv"
 	"strings"
 
 	"github.com/goplus/gogen"
@@ -338,4 +339,42 @@ func makeMainSig(recv *types.Var, f *types.Func) *types.Signature {
 	return types.NewSignatureType(recv, nil, nil, types.NewTuple(params...), nil, false)
 }
 
+func astFnClassfname(c *gmxClass) *ast.FuncDecl {
+	return &ast.FuncDecl{
+		Name: &ast.Ident{
+			Name: "Classfname",
+		},
+		Type: &ast.FuncType{
+			Params: &ast.FieldList{},
+			Results: &ast.FieldList{
+				List: []*ast.Field{
+					{Type: &ast.Ident{Name: "string"}},
+				},
+			},
+		},
+		Body: &ast.BlockStmt{
+			List: []ast.Stmt{
+				&ast.ReturnStmt{
+					Results: []ast.Expr{
+						&ast.BasicLit{Kind: token.STRING, Value: strconv.Quote(c.clsfile)},
+					},
+				},
+			},
+		},
+	}
+}
+
+func astEmptyFunc(entry string) *ast.FuncDecl {
+	return &ast.FuncDecl{
+		Name: &ast.Ident{
+			Name: entry,
+		},
+		Type: &ast.FuncType{
+			Params: &ast.FieldList{},
+		},
+		Body:   &ast.BlockStmt{},
+		Shadow: true,
+	}
+}
+
 // -----------------------------------------------------------------------------
diff --git a/cl/compile.go b/cl/compile.go
index 5359e50c2..c80bfdea4 100644
--- a/cl/compile.go
+++ b/cl/compile.go
@@ -854,28 +854,7 @@ func preloadGopFile(p *gogen.Package, ctx *blockCtx, file string, f *ast.File, c
 		}}}
 		// func Classfname() string
 		if spxClass {
-			f.Decls = append(f.Decls, &ast.FuncDecl{
-				Name: &ast.Ident{
-					Name: "Classfname",
-				},
-				Type: &ast.FuncType{
-					Params: &ast.FieldList{},
-					Results: &ast.FieldList{
-						List: []*ast.Field{
-							{Type: &ast.Ident{Name: "string"}},
-						},
-					},
-				},
-				Body: &ast.BlockStmt{
-					List: []ast.Stmt{
-						&ast.ReturnStmt{
-							Results: []ast.Expr{
-								&ast.BasicLit{Kind: token.STRING, Value: strconv.Quote(c.clsfile)},
-							},
-						},
-					},
-				},
-			})
+			f.Decls = append(f.Decls, astFnClassfname(c))
 		}
 	}
 	if d := f.ShadowEntry; d != nil {
@@ -892,16 +871,7 @@ func preloadGopFile(p *gogen.Package, ctx *blockCtx, file string, f *ast.File, c
 			}
 		}
 		if !hasEntry {
-			f.Decls = append(f.Decls, &ast.FuncDecl{
-				Name: &ast.Ident{
-					Name: entry,
-				},
-				Type: &ast.FuncType{
-					Params: &ast.FieldList{},
-				},
-				Body:   &ast.BlockStmt{},
-				Shadow: true,
-			})
+			f.Decls = append(f.Decls, astEmptyFunc(entry))
 		}
 	}
 	preloadFile(p, ctx, f, goFile, !conf.Outline)