patch 7.4.2024
Problem:    More buf_valid() calls can be optimized.
Solution:   Use bufref_valid() instead.
diff --git a/src/proto/buffer.pro b/src/proto/buffer.pro
index e2adf5c..183f79a 100644
--- a/src/proto/buffer.pro
+++ b/src/proto/buffer.pro
@@ -7,7 +7,7 @@
 void buf_clear_file(buf_T *buf);
 void buf_freeall(buf_T *buf, int flags);
 void goto_buffer(exarg_T *eap, int start, int dir, int count);
-void handle_swap_exists(buf_T *old_curbuf);
+void handle_swap_exists(bufref_T *old_curbuf);
 char_u *do_bufdel(int command, char_u *arg, int addr_count, int start_bnr, int end_bnr, int forceit);
 int do_buffer(int action, int start, int dir, int count, int forceit);
 void set_curbuf(buf_T *buf, int action);