patch 7.4.2017
Problem: When there are many errors adding them to the quickfix list takes
a long time.
Solution: Add BLN_NOOPT. Don't call buf_valid() in buf_copy_options().
Remember the last file name used. When going through the buffer
list start from the end of the list. Only call buf_valid() when
autocommands were executed.
diff --git a/src/vim.h b/src/vim.h
index 7d76504..4d6f934 100644
--- a/src/vim.h
+++ b/src/vim.h
@@ -941,6 +941,7 @@
#define BLN_LISTED 2 /* put new buffer in buffer list */
#define BLN_DUMMY 4 /* allocating dummy buffer */
#define BLN_NEW 8 /* create a new buffer */
+#define BLN_NOOPT 16 /* don't copy options to existing buffer */
/* Values for in_cinkeys() */
#define KEY_OPEN_FORW 0x101