1 files changed, 1 insertions, 1 deletions
diff --git a/io.c b/io.c
index 2c31212e5b..50f4756ba3 100644
--- a/io.c
+++ b/io.c
@@ -1681,7 +1681,7 @@ rb_io_getline_fast(fptr, delim)
 
 static int
 rscheck(rsptr, rslen, rs)
-    char *rsptr;
+    const char *rsptr;
     long rslen;
     VALUE rs;
 {