diff --git a/compiler/go.mod b/compiler/go.mod
index 01c2b18d..9e24daab 100644
--- a/compiler/go.mod
+++ b/compiler/go.mod
@@ -1,6 +1,6 @@
 module github.com/goplus/llgo/compiler
 
-go 1.23
+go 1.22.0
 
 require (
 	github.com/goplus/gogen v1.16.4
diff --git a/compiler/ssa/package.go b/compiler/ssa/package.go
index e8d8ed71..abc6a291 100644
--- a/compiler/ssa/package.go
+++ b/compiler/ssa/package.go
@@ -283,7 +283,7 @@ func (p Program) rtNamed(name string) *types.Named {
 	t := p.runtime().Scope().Lookup(name).Type()
 	for {
 		if alias, ok := t.(*types.Alias); ok {
-			t = alias.Rhs()
+			t = types.Unalias(alias)
 		} else {
 			break
 		}
diff --git a/compiler/ssa/type.go b/compiler/ssa/type.go
index 60a39d7a..900fa542 100644
--- a/compiler/ssa/type.go
+++ b/compiler/ssa/type.go
@@ -388,6 +388,8 @@ func (p Program) toType(raw types.Type) Type {
 		return &aType{llvm.ArrayType(elem.ll, int(t.Len())), typ, vkArray}
 	case *types.Chan:
 		return &aType{llvm.PointerType(p.rtChan(), 0), typ, vkChan}
+	case *types.Alias:
+		return p.toType(types.Unalias(t))
 	}
 	panic(fmt.Sprintf("toLLVMType: todo - %T\n", raw))
 }
diff --git a/compiler/ssa/type_cvt.go b/compiler/ssa/type_cvt.go
index eb347cae..454266a7 100644
--- a/compiler/ssa/type_cvt.go
+++ b/compiler/ssa/type_cvt.go
@@ -115,6 +115,8 @@ func (p goTypes) cvtType(typ types.Type) (raw types.Type, cvt bool) {
 		return p.cvtTuple(t)
 	case *types.TypeParam:
 		return typ.Underlying(), false
+	case *types.Alias:
+		return types.Unalias(t), true
 	default:
 		panic(fmt.Sprintf("cvtType: unexpected type - %T", typ))
 	}