patch 7.4.2101
Problem:    Looping over windows, buffers and tab pages is inconsistant.
Solution:   Use FOR_ALL_ macros everywhere. (Yegappan Lakshmanan)
diff --git a/src/edit.c b/src/edit.c
index 4bce8a3..a60d922 100644
--- a/src/edit.c
+++ b/src/edit.c
@@ -4239,7 +4239,7 @@
 
     if (!compl_started)
     {
-	for (ins_buf = firstbuf; ins_buf != NULL; ins_buf = ins_buf->b_next)
+	FOR_ALL_BUFFERS(ins_buf)
 	    ins_buf->b_scanned = 0;
 	found_all = FALSE;
 	ins_buf = curbuf;