fix: substitute recursive struct type by interface{} in function argu…

…ments

_test/struct38.go

@@ -0,0 +1,24 @@
+package main
+
+type T struct {
+	f func(t *T1)
+	y *xxx
+}
+
+type T1 struct {
+	T
+}
+
+type xxx struct{}
+
+var (
+	x1 *T1 = x
+	x      = &T1{}
+)
+
+func main() {
+	println("ok")
+}
+
+// Output:
+// ok

interp/gta.go

@@ -1,8 +1,6 @@
 package interp
 
-import (
-	"reflect"
-)
+import "reflect"
 
 // gta performs a global types analysis on the AST, registering types,
 // variables and functions symbols at package level, prior to CFG.

interp/type.go

@@ -905,6 +905,9 @@ var interf = reflect.TypeOf(new(interface{})).Elem()
 
 func (t *itype) refType(defined map[string]*itype, wrapRecursive bool) reflect.Type {
 	if t.rtype != nil {
+		if wrapRecursive && t.cat == structT && defined[t.name] != nil {
+			return interf
+		}
 		return t.rtype
 	}