do not write null sha1s to on-disk index

diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt
index de2206bd5ccf936e97cfde5def4388cb3439300c..ba7cd13483194399762b0f48e218ddb4011dfcf1 100644 (file)
--- a/Documentation/diff-options.txt
+++ b/Documentation/diff-options.txt
@@ -411,6 +411,10 @@ endif::git-format-patch[]
        Show the context between diff hunks, up to the specified number
        of lines, thereby fusing hunks that are close to each other.
 
+-W::
+--function-context::
+       Show whole surrounding functions of changes.
+
 ifndef::git-format-patch[]
 ifndef::git-log[]
 --exit-code::