Declarations and code do not mix in C90, not even within UNIV_DEBUG.

storage/innodb_plugin/buf/buf0flu.c

@@ -1710,9 +1710,9 @@ buf_flush_validate_low(void)
 		ut_a(om > 0);
 
 		if (UNIV_LIKELY_NULL(buf_pool->flush_rbt)) {
+			buf_page_t* rpage;
 			ut_a(rnode);
-			buf_page_t* rpage = *rbt_value(buf_page_t*,
-						       rnode);
+			rpage = *rbt_value(buf_page_t*, rnode);
 			ut_a(rpage);
 			ut_a(rpage == bpage);
 			rnode = rbt_next(buf_pool->flush_rbt, rnode);

storage/innodb_plugin/sync/sync0rw.c

@@ -335,10 +335,13 @@ rw_lock_validate(
 /*=============*/
 	rw_lock_t*	lock)	/*!< in: rw-lock */
 {
+	ulint	waiters;
+	lint	lock_word;
+
 	ut_a(lock);
 
-	ulint waiters = rw_lock_get_waiters(lock);
-	lint lock_word = lock->lock_word;
+	waiters = rw_lock_get_waiters(lock);
+	lock_word = lock->lock_word;
 
 	ut_ad(lock->magic_n == RW_LOCK_MAGIC_N);
 	ut_a(waiters == 0 || waiters == 1);