diff --git a/chore/_xtool/llcppsigfetch/parse/cvt.go b/chore/_xtool/llcppsigfetch/parse/cvt.go
index c77863e3..26c66fab 100644
--- a/chore/_xtool/llcppsigfetch/parse/cvt.go
+++ b/chore/_xtool/llcppsigfetch/parse/cvt.go
@@ -14,11 +14,17 @@ import (
 	"github.com/goplus/llgo/chore/llcppg/token"
 )
 
+type FileEntry struct {
+	Path string
+	Doc  *ast.File
+}
+
 type Converter struct {
-	Files  map[string]*ast.File
-	curLoc ast.Location
-	index  *clang.Index
-	unit   *clang.TranslationUnit
+	Files     []*FileEntry
+	FileOrder []string // todo(zzy): more efficient struct
+	curLoc    ast.Location
+	index     *clang.Index
+	unit      *clang.TranslationUnit
 
 	typeDecls map[string]ast.Decl // cursorUsr -> ast.Decl
 
@@ -64,7 +70,7 @@ func NewConverter(config *Config) (*Converter, error) {
 	}
 
 	return &Converter{
-		Files:        make(map[string]*ast.File),
+		Files:        make([]*FileEntry, 0),
 		index:        index,
 		unit:         unit,
 		anonyTypeMap: make(map[string]bool),
@@ -169,16 +175,19 @@ func (ct *Converter) GetCurFile() *ast.File {
 	if ct.curLoc.File == "" {
 		return nil
 	}
-	file, ok := ct.Files[ct.curLoc.File]
-	if !ok {
-		file = &ast.File{
-			Decls:    make([]ast.Decl, 0),
-			Includes: make([]*ast.Include, 0),
-			Macros:   make([]*ast.Macro, 0),
+	// todo(zzy): more efficient
+	for i, entry := range ct.Files {
+		if entry.Path == ct.curLoc.File {
+			return ct.Files[i].Doc
 		}
-		ct.Files[ct.curLoc.File] = file
 	}
-	return file
+	newDoc := &ast.File{
+		Decls:    make([]ast.Decl, 0),
+		Includes: make([]*ast.Include, 0),
+		Macros:   make([]*ast.Macro, 0),
+	}
+	ct.Files = append(ct.Files, &FileEntry{Path: ct.curLoc.File, Doc: newDoc})
+	return newDoc
 }
 
 func (ct *Converter) SetAnonyType(cursor clang.Cursor) {
@@ -300,7 +309,7 @@ func visitTop(cursor, parent clang.Cursor, clientData unsafe.Pointer) clang.Chil
 	return clang.ChildVisit_Continue
 }
 
-func (ct *Converter) Convert() (map[string]*ast.File, error) {
+func (ct *Converter) Convert() ([]*FileEntry, error) {
 	cursor := ct.unit.Cursor()
 	// visit top decls (struct,class,function & macro,include)
 	clang.VisitChildren(cursor, visitTop, c.Pointer(ct))
diff --git a/chore/_xtool/llcppsigfetch/parse/dump.go b/chore/_xtool/llcppsigfetch/parse/dump.go
index 553de95c..bb58a02c 100644
--- a/chore/_xtool/llcppsigfetch/parse/dump.go
+++ b/chore/_xtool/llcppsigfetch/parse/dump.go
@@ -6,22 +6,22 @@ import (
 	"github.com/goplus/llgo/chore/llcppg/ast"
 )
 
-func MarshalOutputASTFiles(files map[string]*ast.File) *cjson.JSON {
+func MarshalOutputASTFiles(files []*FileEntry) *cjson.JSON {
 	root := cjson.Array()
-	for path, file := range files {
+	for _, entry := range files {
 		f := cjson.Object()
-		path := cjson.String(c.AllocaCStr(path))
+		path := cjson.String(c.AllocaCStr(entry.Path))
 		f.SetItem(c.Str("path"), path)
-		f.SetItem(c.Str("doc"), MarshalASTFile(file))
+		f.SetItem(c.Str("doc"), MarshalASTFile(entry.Doc))
 		root.AddItem(f)
 	}
 	return root
 }
 
-func MarshalASTFiles(files map[string]*ast.File) *cjson.JSON {
+func MarshalASTFiles(files []*FileEntry) *cjson.JSON {
 	root := cjson.Object()
-	for path, file := range files {
-		root.SetItem(c.AllocaCStr(path), MarshalASTFile(file))
+	for _, entry := range files {
+		root.SetItem(c.AllocaCStr(entry.Path), MarshalASTFile(entry.Doc))
 	}
 	return root
 }
diff --git a/chore/_xtool/llcppsigfetch/parse/parse.go b/chore/_xtool/llcppsigfetch/parse/parse.go
index 90684c80..9a1c3978 100644
--- a/chore/_xtool/llcppsigfetch/parse/parse.go
+++ b/chore/_xtool/llcppsigfetch/parse/parse.go
@@ -4,17 +4,16 @@ import (
 	"errors"
 
 	"github.com/goplus/llgo/c/cjson"
-	"github.com/goplus/llgo/chore/llcppg/ast"
 )
 
 type Context struct {
-	Files map[string]*ast.File
+	Files []*FileEntry
 	IsCpp bool
 }
 
 func NewContext(isCpp bool) *Context {
 	return &Context{
-		Files: make(map[string]*ast.File),
+		Files: make([]*FileEntry, 0),
 		IsCpp: isCpp,
 	}
 }
@@ -35,23 +34,21 @@ func (p *Context) ProcessFiles(files []string) error {
 
 // parse file and add it to the context,avoid duplicate parsing
 func (p *Context) processFile(path string) error {
-	if _, exists := p.Files[path]; exists {
-		return nil
+	for _, entry := range p.Files {
+		if entry.Path == path {
+			return nil
+		}
 	}
-	parsedfiles, err := p.parseFile(path)
+	parsedFiles, err := p.parseFile(path)
 	if err != nil {
 		return errors.New("failed to parse file: " + path)
 	}
 
-	for path, file := range parsedfiles {
-		if _, exist := p.Files[path]; !exist {
-			p.Files[path] = file
-		}
-	}
+	p.Files = append(p.Files, parsedFiles...)
 	return nil
 }
 
-func (p *Context) parseFile(path string) (map[string]*ast.File, error) {
+func (p *Context) parseFile(path string) ([]*FileEntry, error) {
 	converter, err := NewConverter(&Config{
 		File:  path,
 		Temp:  false,