checkout doc: clarify command line args for "checkout paths" mode

diff --git a/Documentation/git-grep.txt b/Documentation/git-grep.txt
index 71f32f35089241bc452cfdccdc6b3e9a30f95366..5033483db496286910dd24507f3374e18ff6c2b5 100644 (file)
--- a/Documentation/git-grep.txt
+++ b/Documentation/git-grep.txt
@@ -161,8 +161,11 @@ OPTIONS
 
 -P::
 --perl-regexp::
-       Use Perl-compatible regexp for patterns. Requires libpcre to be
-       compiled in.
+       Use Perl-compatible regular expressions for patterns.
++
+Support for these types of regular expressions is an optional
+compile-time dependency. If Git wasn't compiled with support for them
+providing this option will cause it to die.
 
 -F::
 --fixed-strings::