get_prop_len opcode returns 0 when argument is 0 per Z-machine spec 1.1.

Copied from Windows Frotz.

diff --git a/src/common/object.c b/src/common/object.c
index d2dc7e65385337ce179c56ba8336a41c7cd9c470..699035bb444ec6d7b31c853ea21884bfd614cc4e 100644 (file)
--- a/src/common/object.c
+++ b/src/common/object.c
@@ -667,6 +667,11 @@ void z_get_prop_len (void)
     zword addr;
     zbyte value;
 
+    if (zargs[0] == 0) {
+       store (0); /* demanded by Spec 1.1 */
+       return;
+    }
+
     /* Back up the property pointer to the property id */
 
     addr = zargs[0] - 1;