Gauche and Chibi pass the tests with this patch
diff --git a/tests-r7rs.scm b/tests-r7rs.scm
index 194718e..fc211e3 100644
--- a/tests-r7rs.scm
+++ b/tests-r7rs.scm
@@ -4,6 +4,7 @@
(import (scheme base)
(scheme char)
(scheme list)
+ (scheme read)
(srfi 171))
(cond-expand
(gauche (import (only (gauche base) compose)