A distinct type based on an array would yield .len == 0

releasenotes.md

@@ -62,6 +62,7 @@
 - Fix unexpected display of macro definition when passing a poisoned expression #2305.
 - `@links` on macros would not be added to calling functions.
 - Fix `Formatter.print` returning incorrect size.
+- A distinct type based on an array would yield .len == 0
 
 ### Stdlib changes
 - Improve contract for readline. #2280

src/compiler/sema_expr.c

@@ -4862,16 +4862,20 @@ static inline bool sema_create_const_len(Expr *expr, Type *type, Type *flat)
 	ASSERT_SPAN(expr, flat == type_flatten(flat) && "Should be flattened already.");
 
 	size_t len;
-	if (type->type_kind == TYPE_CONST_ENUM) goto ENUMS;
+	if (type->type_kind == TYPE_CONST_ENUM)
+	{
+		len = vec_size(type->decl->enums.values);
+		expr_rewrite_const_int(expr, type_usz, len);
+		return true;
+	}
 	switch (flat->type_kind)
 	{
 		case TYPE_ARRAY:
 		case TYPE_VECTOR:
-			len = type->array.len;
+			len = flat->array.len;
 			break;
 		case TYPE_ENUM:
-ENUMS:
-			len = vec_size(type->decl->enums.values);
+			len = vec_size(flat->decl->enums.values);
 			break;
 		case TYPE_INFERRED_ARRAY:
 		case TYPE_FLEXIBLE_ARRAY:

test/test_suite/compile_time_introspection/len_distinct.c3t

@@ -0,0 +1,6 @@
+typedef Foo = int[32];
+fn int main()
+{
+	$assert(Foo.len == 32);
+	return 0;
+}