assert() that itersvp is non-NULL.

Coverity CID 135011 Explicit null derefenced

In pp_iter() there are multiple derefers of *itersvp, but at the
setting of itersvp the CxITERVAR() can return NULL, add an assert()
to catch the badness in debug builds (as the Coverity builds are).

1 files changed, 1 insertions, 0 deletions

diff --git a/pp_hot.c b/pp_hot.c
index 1a2a725f76..d5c11724c3 100644
--- a/pp_hot.c
+++ b/pp_hot.c
@@ -2632,6 +2632,7 @@ PP(pp_iter)
 
     cx = CX_CUR();
     itersvp = CxITERVAR(cx);
+    assert(itersvp);
 
     switch (CxTYPE(cx)) {