cgen: fix assigning optional of multi_return with heap (#16049)

vlib/v/gen/c/assign.v

@@ -529,9 +529,6 @@ fn (mut g Gen) gen_multi_return_assign(node &ast.AssignStmt, return_type ast.Typ
 		styp := if ident.name in g.defer_vars { '' } else { g.typ(node.left_types[i]) }
 		if node.op == .decl_assign {
 			g.write('$styp ')
-			if is_auto_heap {
-				g.write('*')
-			}
 		}
 		if lx.is_auto_deref_var() {
 			g.write('*')

vlib/v/tests/assign_optional_of_multi_return_with_heap_test.v

@@ -0,0 +1,50 @@
+struct Poss1 {}
+
+struct Poss2 {}
+
+type Possibilities = Poss1 | Poss2
+
+// comment out this attribute to make error go away BUT now you need to remember to use &PossOwner everytime you create new instance :(
+[heap]
+pub struct PossOwner {
+pub:
+	name    string
+	details Possibilities
+}
+
+fn (t PossOwner) get_file(path string) ?(PossOwner, Poss1) {
+	match t.details {
+		Poss1 { return t, t.details }
+		else { return error('not a file') }
+	}
+}
+
+fn (item PossOwner) check() ?int {
+	assert item.name == 'x'
+
+	return 0
+}
+
+fn somefun() ?int {
+	t := PossOwner{
+		name: 'x'
+		details: Poss1{}
+	}
+
+	path_info, _ := t.get_file('') or {
+		println('NOTOK1')
+		return 1
+	}
+
+	_ := path_info.check() or {
+		println('NOTOK2')
+		return 2
+	}
+
+	return 0
+}
+
+fn test_assign_optional_of_multi_return_with_heap() {
+	somefun() or { return }
+	println('success')
+}