1 files changed, 5 insertions, 0 deletions

diff --git a/src/lj_crecord.c b/src/lj_crecord.c
index f6824bff..9b0e0d8e 100644
--- a/src/lj_crecord.c
+++ b/src/lj_crecord.c
@@ -1050,6 +1050,11 @@ static void crec_alloc(jit_State *J, RecordFFData *rd, CTypeID id)
           dp = emitir(IRT(IR_ADD, IRT_PTR), trcd,
                       lj_ir_kintp(J, df->size + sizeof(GCcdata)));
           crec_ct_tv(J, dc, dp, sp, sval);
+          if ((d->info & CTF_UNION)) {
+            if (d->size != dc->size)  /* NYI: partial init of union. */
+              lj_trace_err(J, LJ_TRERR_NYICONV);
+            break;
+          }
         } else if (!ctype_isconstval(df->info)) {
           /* NYI: init bitfields and sub-structures. */
           lj_trace_err(J, LJ_TRERR_NYICONV);