Need to extend the stack when using warn() without

an argument (this fixes bug #41716)

p4raw-id: //depot/perl@30513

1 files changed, 1 insertions, 0 deletions

diff --git a/pp_sys.c b/pp_sys.c
index c35fb5b2b2..29638d91b3 100644
--- a/pp_sys.c
+++ b/pp_sys.c
@@ -437,6 +437,7 @@ PP(pp_warn)
     else if (SP == MARK) {
 	tmpsv = &PL_sv_no;
 	EXTEND(SP, 1);
+	SP = MARK + 1;
     }
     else {
 	tmpsv = TOPs;