xargs: make -I imply -r

Make -I imply -r (GNU findutils seems to do the same).

Fixes the following bug:

        $ echo -n | xargs -I% echo %
        Segmentation fault

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/findutils/xargs.c b/findutils/xargs.c
index 5870b8a16..69f83b128 100644
--- a/findutils/xargs.c
+++ b/findutils/xargs.c
@@ -577,6 +577,9 @@ int xargs_main(int argc, char **argv)
                 G.argv = argv;
                 argc = 0;
                 read_args = process_stdin_with_replace;
+                /* Make -I imply -r. GNU findutils seems to do the same: */
+                /* (otherwise "echo -n | xargs -I% echo %" would SEGV) */
+                opt |= OPT_NO_EMPTY;
         } else
 #endif
         {