Doc changes for cache-long-scans

Ref: http://debbugs.gnu.org/15797#65

* doc/lispref/display.texi (Truncation):
* doc/lispref/positions.texi (Screen Lines): Do not mention cache-long-scans.

* src/buffer.c (cache-long-scans): Doc fix.

* etc/NEWS: Related edit.

3 files changed, 12 insertions, 3 deletions

diff --git a/doc/lispref/ChangeLog b/doc/lispref/ChangeLog
index b38256a4492..eff328caa60 100644
--- a/doc/lispref/ChangeLog
+++ b/doc/lispref/ChangeLog
@@ -1,3 +1,8 @@
+2014-02-06  Glenn Morris  <rgm@gnu.org>
+
+        * display.texi (Truncation):
+        * positions.texi (Screen Lines): Do not mention cache-long-scans.
+
 2014-01-31  Juri Linkov  <juri@jurta.org>
 
         * searching.texi (String Search): Incremental word search fixes.
diff --git a/doc/lispref/display.texi b/doc/lispref/display.texi
index 9123e940e08..7d52ad7207b 100644
--- a/doc/lispref/display.texi
+++ b/doc/lispref/display.texi
@@ -214,6 +214,7 @@ A line prefix may also be specified for regions of text using the
 over the @code{line-prefix} variable.  @xref{Special Properties}.
 @end defvar
 
+@ignore
   If your buffer contains only very short lines, you might find it
 advisable to set @code{cache-long-scans} to @code{nil}.
 
@@ -227,6 +228,7 @@ Turning off the cache speeds up processing of short lines somewhat.
 
 This variable is automatically buffer-local in every buffer.
 @end defvar
+@end ignore
 
 @node The Echo Area
 @section The Echo Area
diff --git a/doc/lispref/positions.texi b/doc/lispref/positions.texi
index 9a9152b4044..f83173e2038 100644
--- a/doc/lispref/positions.texi
+++ b/doc/lispref/positions.texi
@@ -486,9 +486,11 @@ flag, and display table may vary between windows).  @xref{Usual
 Display}.
 
   These functions scan text to determine where screen lines break, and
-thus take time proportional to the distance scanned.  If you intend to
-use them heavily, Emacs provides caches which may improve the
-performance of your code.  @xref{Truncation, cache-long-scans}.
+thus take time proportional to the distance scanned.
+@ignore
+If you intend to use them heavily, Emacs provides caches which may
+improve the performance of your code.  @xref{Truncation, cache-long-scans}.
+@end ignore
 
 @defun vertical-motion count &optional window
 This function moves point to the start of the screen line @var{count}