dev-manual: improve descriptions of 'bitbake -S printdiff'

Try to particularly emphasize that it can be used to find
out why something rebuilds when it shouldn't.

(From yocto-docs rev: cfaf2707b4a77888316d5eb24bf41ccc21e2c12b)

Signed-off-by: Alexander Kanavin <alex@linutronix.de>
Reviewed-by: Michael Opdenacker <michael.opdenacker@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 3 insertions, 4 deletions

diff --git a/documentation/dev-manual/building.rst b/documentation/dev-manual/building.rst
index 7fcac33b75..fe502690dd 100644
--- a/documentation/dev-manual/building.rst
+++ b/documentation/dev-manual/building.rst
@@ -775,10 +775,9 @@ your tunings to best consider build times and package feed maintenance.
       in the script for information on how to use the tool.
 
    -  *BitBake's "-S printdiff" Option:* Using this option causes
-      BitBake to try to establish the closest signature match it can
-      (e.g. in the shared state cache) and then run ``bitbake-diffsigs``
-      over the matches to determine the stamps and delta where these two
-      stamp trees diverge.
+      BitBake to try to establish the most recent signature match
+      (e.g. in the shared state cache) and then compare matched signatures
+      to determine the stamps and delta where these two stamp trees diverge.
 
 Building Software from an External Source
 =========================================