1 files changed, 1 insertions, 0 deletions
diff --git a/ext/zlib/zlib.c b/ext/zlib/zlib.c
index c8c4407d08..ee98089f0a 100644
--- a/ext/zlib/zlib.c
+++ b/ext/zlib/zlib.c
@@ -759,6 +759,7 @@ zstream_run(z, src, len, flush)
     zstream_reset_input(z);
     if (z->stream.avail_in > 0) {
 	zstream_append_input(z, z->stream.next_in, z->stream.avail_in);
+        guard = Qnil; /* prevent tail call to make guard effective */
     }
 }