Fix bogus assertions

storage/innobase/dict/dict0mem.cc

@@ -1467,7 +1467,10 @@ void dict_table_t::instant_column(const dict_table_t& table, const ulint* map)
 				non_pk_col_map[i - u] = field->col->ind + 1;
 				continue;
 			}
-			ut_ad(field->col == table.instant->dropped + n_drop++);
+			ut_ad(field->col >= table.instant->dropped);
+			ut_ad(field->col < table.instant->dropped
+			      + table.instant->n_dropped);
+			ut_d(n_drop++);
 			field->col += instant->dropped
 				- table.instant->dropped;
 		}

storage/innobase/handler/handler0alter.cc

@@ -397,8 +397,7 @@ struct ha_innobase_inplace_ctx : public inplace_alter_handler_ctx
 			const uint n_fields = instant->n_fields
 				+ instant_table->n_dropped();
 
-			DBUG_ASSERT(n_fields
-				    >= old->n_fields + old_table->n_dropped());
+			DBUG_ASSERT(n_fields >= old->n_fields);
 			dict_field_t* fields = static_cast<dict_field_t*>(
 				mem_heap_zalloc(instant_table->heap,
 						n_fields * sizeof *fields));