diff --git a/opcodes.c b/opcodes.c
index e3837e42..8267f396 100644
--- a/opcodes.c
+++ b/opcodes.c
@@ -35,8 +35,8 @@ _OP(SEXP_OPC_GENERIC, SEXP_OP_CHAR_UPCASE, 1, 0, SEXP_CHAR, 0, 0, "char-upcase",
 _OP(SEXP_OPC_GENERIC, SEXP_OP_CHAR_DOWNCASE, 1, 0, SEXP_CHAR, 0, 0, "char-downcase", 0, NULL),
 _OP(SEXP_OPC_ARITHMETIC,     SEXP_OP_ADD, 0, 1, SEXP_FIXNUM, 0, 0, "+", SEXP_ZERO, NULL),
 _OP(SEXP_OPC_ARITHMETIC,     SEXP_OP_MUL, 0, 1, SEXP_FIXNUM, 0, 0, "*", SEXP_ONE, NULL),
-_OP(SEXP_OPC_ARITHMETIC,     SEXP_OP_SUB, 0, 1, SEXP_FIXNUM, 0, 1, "-", SEXP_ZERO, NULL),
-_OP(SEXP_OPC_ARITHMETIC,     SEXP_OP_DIV, 0, 1, SEXP_FIXNUM, 0, 1, "/", SEXP_ONE, NULL),
+_OP(SEXP_OPC_ARITHMETIC,     SEXP_OP_SUB, 1, 1, SEXP_FIXNUM, 0, 1, "-", SEXP_ZERO, NULL),
+_OP(SEXP_OPC_ARITHMETIC,     SEXP_OP_DIV, 1, 1, SEXP_FIXNUM, 0, 1, "/", SEXP_ONE, NULL),
 _OP(SEXP_OPC_ARITHMETIC,     SEXP_OP_QUOTIENT, 2, 0, SEXP_FIXNUM, SEXP_FIXNUM, 0, "quotient", 0, NULL),
 _OP(SEXP_OPC_ARITHMETIC,     SEXP_OP_REMAINDER, 2, 0, SEXP_FIXNUM, SEXP_FIXNUM, 0, "remainder", 0, NULL),
 _OP(SEXP_OPC_ARITHMETIC_CMP, SEXP_OP_LT,  2, 1, SEXP_FIXNUM, 0, 0, "<", 0, NULL),