1 files changed, 10 insertions, 0 deletions
diff --git a/dev/fallback.lisp b/dev/fallback.lisp
new file mode 100644
index 000000000000..40a5219824e5
--- /dev/null
+++ b/dev/fallback.lisp
@@ -0,0 +1,10 @@
+(in-package #:trivial-backtrace)
+
+(eval-when (:compile-toplevel :load-toplevel :execute)
+  (unless (fboundp 'map-backtrace)
+    (defun map-backtrace (func)
+      (declare (ignore func))))
+
+  (unless (fboundp 'print-backtrace-to-stream)
+    (defun print-backtrace-to-stream (stream)
+      (format stream "~&backtrace output unavailable.~%"))))