patch 7.4.742
Problem: Cannot specify a vertical split when loading a buffer for a
quickfix command.
Solution: Add the "vsplit" value to 'switchbuf'. (Brook Hong)
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 3121039..9cdf9bb 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -7067,6 +7067,7 @@
split If included, split the current window before loading
a buffer for a |quickfix| command that display errors.
Otherwise: do not split, use current window.
+ vsplit Just like "split" but split vertically.
newtab Like "split", but open a new tab page. Overrules
"split" when both are present.