Only allow SvPVX() on SVt_PVIO when IOf_FAKE_DIRP is set.

1 files changed, 4 insertions, 1 deletions

diff --git a/sv.h b/sv.h
index 9c6dfd866c..adadab36cb 100644
--- a/sv.h
+++ b/sv.h
@@ -547,7 +547,8 @@ struct xpvio {
 #define IOf_DIDTOP	8	/* just did top of form */
 #define IOf_UNTAINT	16	/* consider this fp (and its data) "safe" */
 #define IOf_NOLINE	32	/* slurped a pseudo-line from empty file */
-#define IOf_FAKE_DIRP	64	/* xio_dirp is fake (source filters kludge) */
+#define IOf_FAKE_DIRP	64	/* xio_dirp is fake (source filters kludge)
+				   Also, when this is set, SvPVX() is valid */
 
 /* The following macros define implementation-independent predicates on SVs. */
 
@@ -1043,6 +1044,8 @@ the scalar's value cannot change unless written to.
 	    assert(SvTYPE(_svpvx) != SVt_PVAV);				\
 	    assert(SvTYPE(_svpvx) != SVt_PVHV);				\
 	    assert(!isGV_with_GP(_svpvx));				\
+	    assert(!(SvTYPE(_svpvx) == SVt_PVIO				\
+		     && !(IoFLAGS(_svpvx) & IOf_FAKE_DIRP)));		\
 	    &((_svpvx)->sv_u.svu_pv);					\
 	 }))
 #    define SvCUR(sv)							\