diff --git a/cl/_testgo/runextest/bar/bar.go b/cl/_testgo/runextest/bar/bar.go
new file mode 100644
index 00000000..5730a5c5
--- /dev/null
+++ b/cl/_testgo/runextest/bar/bar.go
@@ -0,0 +1,5 @@
+package bar
+
+func Bar() int {
+	return 2
+}
diff --git a/cl/_testgo/runextest/bar/bar_test.go b/cl/_testgo/runextest/bar/bar_test.go
new file mode 100644
index 00000000..8d4c0438
--- /dev/null
+++ b/cl/_testgo/runextest/bar/bar_test.go
@@ -0,0 +1,13 @@
+package bar_test
+
+import (
+	"testing"
+
+	"github.com/goplus/llgo/cl/_testgo/runextest/bar"
+)
+
+func TestBar(t *testing.T) {
+	if bar.Bar() != 2 {
+		t.Fatal("Bar() != 2")
+	}
+}
diff --git a/cl/_testgo/runextest/bar/barinner/barinner.go b/cl/_testgo/runextest/bar/barinner/barinner.go
new file mode 100644
index 00000000..b37a5d6d
--- /dev/null
+++ b/cl/_testgo/runextest/bar/barinner/barinner.go
@@ -0,0 +1,5 @@
+package barinner
+
+func BarInner() int {
+	return 2
+}
diff --git a/cl/_testgo/runextest/bar/barinner/barinner_test.go b/cl/_testgo/runextest/bar/barinner/barinner_test.go
new file mode 100644
index 00000000..12c543cd
--- /dev/null
+++ b/cl/_testgo/runextest/bar/barinner/barinner_test.go
@@ -0,0 +1,13 @@
+package barinner_test
+
+import (
+	"testing"
+
+	"github.com/goplus/llgo/cl/_testgo/runextest/bar/barinner"
+)
+
+func TestBarInner(t *testing.T) {
+	if barinner.BarInner() != 2 {
+		t.Fatal("BarInner() != 2")
+	}
+}
diff --git a/cl/_testgo/runextest/foo/foo.go b/cl/_testgo/runextest/foo/foo.go
new file mode 100644
index 00000000..96b79fa4
--- /dev/null
+++ b/cl/_testgo/runextest/foo/foo.go
@@ -0,0 +1,5 @@
+package foo
+
+func Foo() int {
+	return 1
+}
diff --git a/cl/_testgo/runextest/foo/foo_test.go b/cl/_testgo/runextest/foo/foo_test.go
new file mode 100644
index 00000000..5c2125e7
--- /dev/null
+++ b/cl/_testgo/runextest/foo/foo_test.go
@@ -0,0 +1,13 @@
+package foo_test
+
+import (
+	"testing"
+
+	"github.com/goplus/llgo/cl/_testgo/runextest/foo"
+)
+
+func TestFoo(t *testing.T) {
+	if foo.Foo() != 1 {
+		t.Fatal("Foo() != 1")
+	}
+}
diff --git a/cl/_testgo/runextest/main.go b/cl/_testgo/runextest/main.go
new file mode 100644
index 00000000..b3fd473c
--- /dev/null
+++ b/cl/_testgo/runextest/main.go
@@ -0,0 +1,16 @@
+package main
+
+import (
+	"github.com/goplus/llgo/cl/_testgo/runextest/bar"
+	"github.com/goplus/llgo/cl/_testgo/runextest/foo"
+)
+
+func Zoo() int {
+	return 3
+}
+
+func main() {
+	println("foo.Foo()", foo.Foo())
+	println("bar.Bar()", bar.Bar())
+	println("Zoo()", Zoo())
+}
diff --git a/cl/_testgo/runextest/main_test.go b/cl/_testgo/runextest/main_test.go
new file mode 100644
index 00000000..385de527
--- /dev/null
+++ b/cl/_testgo/runextest/main_test.go
@@ -0,0 +1,11 @@
+package main
+
+import (
+	"testing"
+)
+
+func TestZoo(t *testing.T) {
+	if Zoo() != 3 {
+		t.Fatal("Zoo() != 3")
+	}
+}
diff --git a/cl/_testgo/runextest/out.ll b/cl/_testgo/runextest/out.ll
new file mode 100644
index 00000000..1c8a0e79
--- /dev/null
+++ b/cl/_testgo/runextest/out.ll
@@ -0,0 +1 @@
+;
\ No newline at end of file
diff --git a/internal/build/build.go b/internal/build/build.go
index 3c45dac1..1c480b25 100644
--- a/internal/build/build.go
+++ b/internal/build/build.go
@@ -252,7 +252,7 @@ func Do(args []string, conf *Config) ([]Package, error) {
 	output := conf.OutFile != ""
 	export, err := crosscompile.Use(conf.Goos, conf.Goarch, IsWasiThreadsEnabled(), IsRpathChangeEnabled())
 	check(err)
-	ctx := &context{env, cfg, progSSA, prog, dedup, patches, make(map[string]none), initial, mode, 0, output, make(map[*packages.Package]bool), make(map[*packages.Package]bool), conf, export}
+	ctx := &context{env, cfg, progSSA, prog, dedup, patches, make(map[string]none), initial, mode, 0, output, make(map[*packages.Package]bool), make(map[*packages.Package]bool), conf, export, false}
 	pkgs, err := buildAllPkgs(ctx, initial, verbose)
 	check(err)
 	if mode == ModeGen {
@@ -282,6 +282,10 @@ func Do(args []string, conf *Config) ([]Package, error) {
 		}
 	}
 
+	if mode == ModeTest && ctx.testFail {
+		mockable.Exit(1)
+	}
+
 	return dpkg, nil
 }
 
@@ -342,6 +346,8 @@ type context struct {
 
 	buildConf    *Config
 	crossCompile crosscompile.Export
+
+	testFail bool
 }
 
 func (c *context) compiler() *clang.Cmd {
@@ -587,7 +593,9 @@ func linkMainPkg(ctx *context, pkg *packages.Package, pkgs []*aPackage, global l
 		if s := cmd.ProcessState; s != nil {
 			exitCode := s.ExitCode()
 			fmt.Fprintf(os.Stderr, "%s: exit code %d\n", app, exitCode)
-			mockable.Exit(exitCode)
+			if !ctx.testFail && exitCode != 0 {
+				ctx.testFail = true
+			}
 		}
 	case ModeRun:
 		args := make([]string, 0, len(conf.RunArgs)+1)
diff --git a/internal/build/build_test.go b/internal/build/build_test.go
index e7e599fd..f2f8730f 100644
--- a/internal/build/build_test.go
+++ b/internal/build/build_test.go
@@ -4,7 +4,9 @@
 package build
 
 import (
+	"bytes"
 	"fmt"
+	"io"
 	"os"
 	"testing"
 
@@ -58,9 +60,36 @@ func TestRun(t *testing.T) {
 }
 
 func TestTest(t *testing.T) {
+	// FIXME(zzy): with builtin package test in a llgo test ./... will cause duplicate symbol error
 	mockRun([]string{"../../cl/_testgo/runtest"}, &Config{Mode: ModeTest})
 }
 
+func TestExtest(t *testing.T) {
+	originalStdout := os.Stdout
+	defer func() { os.Stdout = originalStdout }()
+
+	r, w, err := os.Pipe()
+	if err != nil {
+		t.Fatalf("os.Pipe failed: %v", err)
+	}
+	os.Stdout = w
+	outputChan := make(chan string)
+	go func() {
+		var data bytes.Buffer
+		io.Copy(&data, r)
+		outputChan <- data.String()
+	}()
+
+	mockRun([]string{"../../cl/_testgo/runextest/..."}, &Config{Mode: ModeTest})
+
+	w.Close()
+	got := <-outputChan
+	expected := "PASS\nPASS\nPASS\nPASS\n"
+	if got != expected {
+		t.Errorf("Expected output %q, but got %q", expected, got)
+	}
+}
+
 func TestCmpTest(t *testing.T) {
 	mockRun([]string{"../../cl/_testgo/runtest"}, &Config{Mode: ModeCmpTest})
 }