* process.c (rb_f_exec): should check whether prog is NULL.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@7165 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 1 insertions, 1 deletions

diff --git a/process.c b/process.c
index bdf651f37b..1ed5dd935a 100644
--- a/process.c
+++ b/process.c
@@ -1267,7 +1267,7 @@ rb_f_exec(argc, argv)
     else {
 	e.argc = argc;
 	e.argv = argv;
-	e.prog = RSTRING(prog)->ptr;
+	e.prog = prog ? RSTRING(prog)->ptr : 0;
     }
     rb_exec(&e);
     rb_sys_fail(e.prog);