diff --git a/.github/actions/setup-deps/action.yml b/.github/actions/setup-deps/action.yml
index 5ab296b2..ffd0f733 100644
--- a/.github/actions/setup-deps/action.yml
+++ b/.github/actions/setup-deps/action.yml
@@ -34,7 +34,7 @@ runs:
         echo "deb http://apt.llvm.org/$(lsb_release -cs)/ llvm-toolchain-$(lsb_release -cs)-${{inputs.llvm-version}} main" | sudo tee /etc/apt/sources.list.d/llvm.list
         wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
         sudo apt-get update
-        sudo apt-get install -y llvm-${{inputs.llvm-version}}-dev clang-${{inputs.llvm-version}} libclang-${{inputs.llvm-version}}-dev lld-${{inputs.llvm-version}} pkg-config libgc-dev libssl-dev zlib1g-dev libffi-dev libcjson-dev libunwind-dev libuv1-dev
+        sudo apt-get install -y llvm-${{inputs.llvm-version}}-dev clang-${{inputs.llvm-version}} libclang-${{inputs.llvm-version}}-dev lld-${{inputs.llvm-version}} pkg-config libgc-dev libssl-dev zlib1g-dev libffi-dev libcjson-dev libunwind-${{inputs.llvm-version}}-dev libuv1-dev libc++-${{inputs.llvm-version}}-dev 
         echo "PATH=/usr/lib/llvm-${{inputs.llvm-version}}/bin:$PATH" >> $GITHUB_ENV
 
         # Install optional deps for demos.
diff --git a/.github/workflows/llgo.yml b/.github/workflows/llgo.yml
index bc375f97..f3f4ed7b 100644
--- a/.github/workflows/llgo.yml
+++ b/.github/workflows/llgo.yml
@@ -70,11 +70,6 @@ jobs:
         with:
           go-version: ${{matrix.go}}
 
-      - name: _xtool build tests
-        run: |
-          cd _xtool
-          llgo build -v ./...
-
       - name: Test demos
         run: |
           # TODO(lijie): force python3-embed to be linked with python-3.12-embed
@@ -88,6 +83,11 @@ jobs:
           export PKG_CONFIG_PATH=$pcdir
           bash .github/workflows/test_demo.sh
 
+      - name: _xtool build tests
+        run: |
+          cd _xtool
+          llgo build -v ./...
+
       - name: Show test result
         run: cat result.md
 
diff --git a/_demo/cppstr/cppstr.go b/_demo/cppstr/cppstr.go
new file mode 100644
index 00000000..25bb941a
--- /dev/null
+++ b/_demo/cppstr/cppstr.go
@@ -0,0 +1,12 @@
+package main
+
+import (
+	"github.com/goplus/lib/c"
+	"github.com/goplus/lib/cpp/std"
+)
+
+func main() {
+	s := std.Str("Hello world\n")
+	c.Printf(s.CStr())
+	print(s.Str(), s.Size(), "\n")
+}
diff --git a/internal/build/build.go b/internal/build/build.go
index 654b3746..44b01134 100644
--- a/internal/build/build.go
+++ b/internal/build/build.go
@@ -953,6 +953,13 @@ func clFiles(ctx *context, files string, pkg *packages.Package, procFile func(li
 
 func clFile(ctx *context, args []string, cFile, expFile string, procFile func(linkFile string), verbose bool) {
 	llFile := expFile + filepath.Base(cFile) + ".ll"
+	ext := filepath.Ext(cFile)
+
+	// default clang++ will use c++ to compile c file,will cause symbol be mangled
+	if ext == ".c" {
+		args = append(args, "-x", "c")
+	}
+
 	args = append(args, "-emit-llvm", "-S", "-o", llFile, "-c", cFile)
 	args = append(args, ctx.crossCompile.CCFLAGS...)
 	args = append(args, ctx.crossCompile.CFLAGS...)
diff --git a/runtime/internal/clite/debug/debug.go b/runtime/internal/clite/debug/debug.go
index f762cb4d..7a1efc4d 100644
--- a/runtime/internal/clite/debug/debug.go
+++ b/runtime/internal/clite/debug/debug.go
@@ -9,7 +9,7 @@ import (
 )
 
 const (
-	LLGoFiles = "_wrap/debug.c"
+	LLGoFiles = "$(llvm-config --cflags): _wrap/debug.c"
 )
 
 type Info struct {
diff --git a/xtool/env/llvm/llvm.go b/xtool/env/llvm/llvm.go
index 82d0d13e..a34757c9 100644
--- a/xtool/env/llvm/llvm.go
+++ b/xtool/env/llvm/llvm.go
@@ -72,7 +72,7 @@ func (e *Env) BinDir() string { return e.binDir }
 
 // Clang returns a new [clang.Cmd] instance.
 func (e *Env) Clang() *clang.Cmd {
-	bin := filepath.Join(e.BinDir(), "clang")
+	bin := filepath.Join(e.BinDir(), "clang++")
 	return clang.New(bin)
 }