Avoid crashes when profiling multi-threaded Lisp (bug#76970)

* src/eval.c (backtrace_p): Check 'current_thread' before
dereferencing it.

(cherry picked from commit fce86c7e9523b9b6c29241ae9d1dea340f0d849c)

diff --git a/src/eval.c b/src/eval.c
index 2e96c5845246ea5acdefef9ecd752cb1af2b68c8..b606990a297c5a53279bff8832b9e3d67d002c10 100644 (file)
--- a/src/eval.c
+++ b/src/eval.c
@@ -159,7 +159,11 @@ set_backtrace_debug_on_exit (union specbinding *pdl, bool doe)
 
 bool
 backtrace_p (union specbinding *pdl)
-{ return specpdl ? pdl >= specpdl : false; }
+{
+  if (current_thread && specpdl && pdl)
+    return pdl >= specpdl;
+  return false;
+}
 
 static bool
 backtrace_thread_p (struct thread_state *tstate, union specbinding *pdl)