diff --git a/ChangeLog b/ChangeLog
index 7a2c35c9bf..362697997f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sat Oct 23 00:20:55 2004  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* ext/zlib/zlib.c (zstream_run): always use zstream_append_input()
+	  to avoid SEGV.  [ruby-dev:24568]
+
 Fri Oct 22 12:02:28 2004  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* eval.c (rb_alias): was warning for wrong condition.
diff --git a/ext/zlib/zlib.c b/ext/zlib/zlib.c
index aed2a26134..633bd2d3bb 100644
--- a/ext/zlib/zlib.c
+++ b/ext/zlib/zlib.c
@@ -699,15 +699,9 @@ zstream_run(z, src, len, flush)
     uInt n;
     int err;
 
-    if (NIL_P(z->input)) {
-	z->stream.next_in = src;
-	z->stream.avail_in = len;
-    }
-    else {
-	zstream_append_input(z, src, len);
-	z->stream.next_in = RSTRING(z->input)->ptr;
-	z->stream.avail_in = RSTRING(z->input)->len;
-    }
+    zstream_append_input(z, src, len);
+    z->stream.next_in = RSTRING(z->input)->ptr;
+    z->stream.avail_in = RSTRING(z->input)->len;
 
     if (z->stream.avail_out == 0) {
 	zstream_expand_buffer(z);