+#define PUSH_SCOPE(scope) \
+ size_t const top = environment_top(); \
+ scope_t *const new_scope = (scope); \
+ scope_t *const old_scope = scope_push(new_scope)
+#define POP_SCOPE() (assert(current_scope == new_scope), scope_pop(old_scope), environment_pop_to(top))
+
+#define PUSH_EXTENSION() \
+ (void)0; \
+ bool const old_gcc_extension = in_gcc_extension; \
+ while (next_if(T___extension__)) { \
+ in_gcc_extension = true; \
+ } \
+ do {} while (0)
+#define POP_EXTENSION() \
+ ((void)(in_gcc_extension = old_gcc_extension))
+