emacs-28 70c229b: Fix regression in gdb-frame-handler

[Lars Ingebrigtsen]

branch: emacs-28
commit 70c229b1fc4f2eb66b5a173cfc8473e4b7ce48f0
Author: Lars Ingebrigtsen <larsi@gnus.org>
Commit: Lars Ingebrigtsen <larsi@gnus.org>

    Fix regression in gdb-frame-handler
    
    * lisp/progmodes/gdb-mi.el (gdb-frame-handler): Protect against
    nil fullnames (bug#52196).
---
 lisp/progmodes/gdb-mi.el | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lisp/progmodes/gdb-mi.el b/lisp/progmodes/gdb-mi.el
index fa54f51..66adc4e 100644
--- a/lisp/progmodes/gdb-mi.el
+++ b/lisp/progmodes/gdb-mi.el
@@ -4600,7 +4600,9 @@ overlay arrow in source buffer."
   (let ((frame (gdb-mi--field (gdb-mi--partial-output) 'frame)))
     (when frame
       (setq gdb-selected-frame (gdb-mi--field frame 'func))
-      (setq gdb-selected-file (file-local-name (gdb-mi--field frame 
'fullname)))
+      (setq gdb-selected-file
+            (when-let ((full (gdb-mi--field frame 'fullname)))
+              (file-local-name full)))
       (setq gdb-frame-number (gdb-mi--field frame 'level))
       (setq gdb-frame-address (gdb-mi--field frame 'addr))
       (let ((line (gdb-mi--field frame 'line)))