Stop string eval from leaking ops

This was leaking:

$ ./miniperl  -Xe 'warn $$; while(1){eval "ok 8"};'
1915 at -e line 1.
^C

This was not:

$ ./miniperl  -Xe 'warn $$; while(1){eval "sub {ok 8}"};'
1916 at -e line 1.
^C

The sub is successfully taking care of its ops when it is freed.  The
eval is not.

I made the mistake of having the CV relinquish ownership of the op
slab after an eval syntax error.  That’s precisely the situation in
which the ops are likely to leak, and for which the slab allocator was
designed.  Duh.

1 files changed, 0 insertions, 1 deletions

diff --git a/pp_ctl.c b/pp_ctl.c
index 869907d41b..27113c0206 100644
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -3462,7 +3462,6 @@ S_doeval(pTHX_ int gimme, CV* outside, U32 seq, HV *hh)
 	PL_op = saveop;
 	if (yystatus != 3) {
 	    if (PL_eval_root) {
-		cv_forget_slab(evalcv);
 		op_free(PL_eval_root);
 		PL_eval_root = NULL;
 	    }