1 files changed, 3 insertions, 2 deletions

diff --git a/src/core/moves.h b/src/core/moves.h
index d07bc19..e3a9bc1 100644
--- a/src/core/moves.h
+++ b/src/core/moves.h
@@ -223,8 +223,9 @@ readmoves(const char *buf, int max, uint8_t *ret)
         uint8_t m;
         int c;
 
-        FOREACH_READMOVE(buf, m, c, max, -1,
-                ret[c] = m;
+        FOREACH_READMOVE(buf, m, c, max, NISSY_ERROR_INVALID_MOVES,
+                if (ret != NULL)
+                        ret[c] = m;
         )
 
         return c;