1 files changed, 1 insertions, 1 deletions
diff --git a/error.c b/error.c
index 564358c83b..844ff76f61 100644
--- a/error.c
+++ b/error.c
@@ -702,7 +702,7 @@ rb_sys_fail(mesg)
 
     err = strerror(errno);
     if (mesg) {
-	buf = ALLOCA_N(char, strlen(err)+strlen(mesg)+1);
+	buf = ALLOCA_N(char, strlen(err)+strlen(mesg)+4);
 	sprintf(buf, "%s - %s", err, mesg);
     }
     else {