bug#17240: [PATCH] grep: no match for the empty string included in multiple patterns

[Norihiro Tanaka]

When the empty string is included in multiple, should match all lines.
However, `grep -F' and grep with regex isn't match.

$ printf 'foo\n\n' >pat
$ cat pat
foo

$ echo abc | env LANG=C grep -f pat
abc  <<== expected
$ echo abc | env LANG=C grep -Ff pat
$   <<== unexpected
$ printf '\(\)\\1x\n\n' >pat
$ cat pat
\(\)\1x

$ echo match | env LANG=C grep -f pat
$    <<== unexpected

Norihiro

patch.txt
Description: Text document