ffi: fix incorrect null-terminated array in op.

* ffi.c (ffi_varray_null_term_in): Rewrite nonsensical
code that refers to the newly created empty output array
as input. We must perform the in semantics on all the
original elements. Then get semantics on any new elements
if the array was extended, and the copy flag is true
(by-ref nuance).

1 files changed, 4 insertions, 3 deletions

diff --git a/ffi.c b/ffi.c
index 049c16d1..0d531724 100644
--- a/ffi.c
+++ b/ffi.c
@@ -2522,6 +2522,7 @@ static val ffi_varray_null_term_in(struct txr_ffi_type *tft, int copy, mem_t *sr
   struct txr_ffi_type *etft = ffi_type_struct(eltype);
   cnum elsize = etft->size;
   cnum offs, i;
+  cnum nelem_orig = c_num(length(vec_in));
 
   for (i = 0, offs = 0; ; i++) {
     mem_t *el = src + offs, *p;
@@ -2533,9 +2534,9 @@ static val ffi_varray_null_term_in(struct txr_ffi_type *tft, int copy, mem_t *sr
     if (p == el + elsize)
       break;
 
-    if (etft->in != 0) {
-      val elval = ref(vec, num_fast(i));
-      vec_push(vec, elval);
+    if (etft->in != 0 && i < nelem_orig) {
+      val elval = ref(vec_in, num_fast(i));
+      vec_push(vec, etft->in(etft, copy, src + offs, elval, self));
     } else if (copy) {
       val elval = etft->get(etft, src + offs, self);
       vec_push(vec, elval);