cgen: fix codegen for nested selector option ptr (fix #24339) (#24345)

vlib/v/gen/c/cgen.v

@@ -4065,11 +4065,12 @@ fn (mut g Gen) selector_expr(node ast.SelectorExpr) {
 			g.write('*')
 		}
 		g.write('${tmp_var} = ')
-		if is_ptr {
+		mut needs_addr := false
+		needs_deref := is_ptr && !is_option_unwrap
+		if needs_deref {
 			g.write('*(')
-		}
-		needs_addr := is_option_unwrap && node.expr !in [ast.Ident, ast.PrefixExpr]
-		if is_option_unwrap {
+		} else if is_option_unwrap && !is_ptr {
+			needs_addr = node.expr !in [ast.Ident, ast.PrefixExpr]
 			if !needs_addr {
 				g.write('&')
 			} else {
@@ -4098,7 +4099,7 @@ fn (mut g Gen) selector_expr(node ast.SelectorExpr) {
 			g.write('.')
 		}
 		g.write(field_name)
-		if is_ptr {
+		if needs_deref {
 			g.write(')')
 		}
 		if needs_addr {

vlib/v/tests/options/option_nested_selector_test.v

@@ -0,0 +1,48 @@
+module main
+
+@[heap]
+interface IGameObject {
+mut:
+	name       string
+	parent     ?&IGameObject
+	next       ?&IGameObject
+	child      ?&IGameObject
+	last_child ?&IGameObject
+	add_child(mut o IGameObject)
+}
+
+@[heap]
+struct GameObject implements IGameObject {
+mut:
+	name       string
+	parent     ?&IGameObject
+	next       ?&IGameObject
+	child      ?&IGameObject
+	last_child ?&IGameObject
+}
+
+fn (mut gameobject GameObject) add_child(mut o IGameObject) {
+	o.parent = gameobject
+	if gameobject.last_child != none {
+		gameobject.last_child.next = o
+	} else {
+		gameobject.child = o
+	}
+	gameobject.last_child = o
+}
+
+fn test_main() {
+	mut v1 := &GameObject{
+		name: 'v1'
+	}
+	mut v2 := &GameObject{
+		name: 'v2'
+	}
+	mut v3 := &GameObject{
+		name: 'v3'
+	}
+	v1.add_child(mut v2)
+	v1.add_child(mut v3)
+
+	assert v1.child?.next?.name == 'v3'
+}