[perl #99850] SEGV when destructor undefs goto &sub

If goto &sub triggers a destructor that undefines &sub, a
crash ensues.

This commit adds an extra check in pp_goto after the unwinding of the
previous sub’s scope.

1 files changed, 12 insertions, 1 deletions

diff --git a/t/op/goto.t b/t/op/goto.t
index f2f91629ec..ad83c29e99 100644
--- a/t/op/goto.t
+++ b/t/op/goto.t
@@ -10,7 +10,7 @@ BEGIN {
 
 use warnings;
 use strict;
-plan tests => 78;
+plan tests => 79;
 our $TODO;
 
 my $deprecated = 0;
@@ -205,6 +205,17 @@ sub f1 {
 }
 f1();
 
+# bug #99850, which is similar - freeing the subroutine we are about to
+# go(in)to during a FREETMPS call should not crash perl.
+
+package _99850 {
+    sub reftype{}
+    DESTROY { undef &reftype }
+    eval { sub { my $guard = bless []; goto &reftype }->() };
+}
+like $@, qr/^Goto undefined subroutine &_99850::reftype at /,
+   'goto &foo undefining &foo on sub cleanup';
+
 # bug #22181 - this used to coredump or make $x undefined, due to
 # erroneous popping of the inner BLOCK context