checker: skip init check for options (fix #25798) (#25830)

Author: dy-tea

vlib/v/checker/struct.v

@@ -1188,6 +1188,10 @@ fn (mut c Checker) check_ref_fields_initialized(struct_sym &ast.TypeSymbol, mut
 				// an embedded struct field
 				continue
 			}
+			if field.typ.has_flag(.option) {
+				// defaults to `none`
+				continue
+			}
 			checked_types << field.typ
 			c.check_ref_fields_initialized(sym, mut checked_types, '${linked_name}.${field.name}',
 				pos)
@@ -1231,6 +1235,10 @@ fn (mut c Checker) check_ref_fields_initialized_note(struct_sym &ast.TypeSymbol,
 				// an embedded struct field
 				continue
 			}
+			if field.typ.has_flag(.option) {
+				// defaults to `none`
+				continue
+			}
 			checked_types << field.typ
 			c.check_ref_fields_initialized(sym, mut checked_types, '${linked_name}.${field.name}',
 				pos)

vlib/v/tests/structs/struct_embed_option_reference_test.v

@@ -0,0 +1,23 @@
+struct Foo {
+	data &int
+}
+
+struct FooHolder {
+	foo ?&Foo
+}
+
+struct FooMain {
+	foo_holder FooHolder
+}
+
+struct FooMain2 {
+	foo_main FooMain
+}
+
+fn test_main() {
+	a := FooMain{}
+	assert a.foo_holder.foo == none
+
+	b := FooMain2{}
+	assert b.foo_main.foo_holder.foo == none
+}