Parametric polymorphic union type

core/fmt/fmt.odin

@@ -353,7 +353,13 @@ write_type :: proc(buf: ^String_Buffer, ti: ^runtime.Type_Info) {
 		write_byte(buf, '}');
 
 	case runtime.Type_Info_Union:
-		write_string(buf, "union {");
+		write_string(buf, "union ");
+		if info.custom_align {
+			write_string(buf, "#align ");
+			write_i64(buf, i64(ti.align), 10);
+			write_byte(buf, ' ');
+		}
+		write_byte(buf, '{');
 		for variant, i in info.variants {
 			if i > 0 do write_string(buf, ", ");
 			write_type(buf, variant);

core/runtime/core.odin

@@ -82,6 +82,7 @@ Type_Info_Union :: struct {
 	variants:   []^Type_Info,
 	tag_offset: uintptr,
 	tag_type:   ^Type_Info,
+	custom_align: bool,
 };
 Type_Info_Enum :: struct {
 	base:      ^Type_Info,