From aface374af5069ad2fc47ce1d4545f025f30ac1c Mon Sep 17 00:00:00 2001 From: Greg Cooper Date: Mon, 28 Apr 2008 04:06:22 +0000 Subject: [PATCH] add a couple of checks for empty stack svn: r9509 --- collects/gui-debugger/debug-tool.ss | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/collects/gui-debugger/debug-tool.ss b/collects/gui-debugger/debug-tool.ss index 66238a8ebb..2fe39b46ca 100644 --- a/collects/gui-debugger/debug-tool.ss +++ b/collects/gui-debugger/debug-tool.ss @@ -894,6 +894,7 @@ (define (can-step-over? frames status) (and (or (not (zero? (get-frame-num))) (eq? status 'entry-break)) + (not (empty? frames)) (not (eq? (frame->end-breakpoint-status (list-ref frames (get-frame-num))) 'invalid)))) (define (can-step-out? frames status) @@ -922,7 +923,9 @@ (send (send (get-frame) get-step-out-button) enable (can-step-out? frames status)) (send (send (get-frame) get-resume-button) enable #t) (send (get-frame) register-stack-frames frames) - (send (get-frame) register-vars (list-ref frames (get-frame-num))) + (send (get-frame) register-vars (if (empty? frames) + empty + (list-ref frames (get-frame-num)))) ;;(fprintf (current-error-port) "break: ~a~n" (map expose-mark frames)) ;;(printf "status = ~a~n" status) (send status-message set-label