1 files changed, 4 insertions, 1 deletions
diff --git a/debug.c b/debug.c
index afef0835..96a97580 100644
--- a/debug.c
+++ b/debug.c
@@ -92,7 +92,10 @@ val debug(val form, val bindings, val data, val line, val pos, val base)
   val loc = source_loc(form);
   cons_bind (lineno, file, loc);
 
-  data = if2(consp(data), car(data));
+  if (consp(data))
+    data = car(data);
+  else if (data == t)
+    data = nil;
 
   if (!step_mode && !memqual(loc, breakpoints) 
       && (debug_depth > next_depth))