duplicate -F switches would overwrite PL_splitstr without freeing

Of course, it wasn't safe to free it before the previous patch,
but it is now.

1 files changed, 10 insertions, 0 deletions

diff --git a/t/run/switchF2.t b/t/run/switchF2.t
index 507459e3d8..5a434eb782 100644
--- a/t/run/switchF2.t
+++ b/t/run/switchF2.t
@@ -38,4 +38,14 @@ SKIP:
                 }, "PL_splitstr freed in each thread");
 }
 
+{
+  # old value of PL_splitstr wasn't freed with multiple switches (it wasn't safe to before)
+  # this would only fail under valgrind/LSAN
+  fresh_perl_is('print $F[1]', "b",
+                {
+                    switches => [ "-F:", "-F," ],
+                    stdin => "a,b,c",
+                }, "PL_splitstr freed on extra -F switch");
+}
+
 done_testing();