$ cat test.asm

dw aa, bb
$ nasm -v
NASM version 2.16.02rc2 compiled on Oct 12 2023
$ nasm test.asm
test.asm:2: error: symbol `aa' not defined
$ ~/proj/nasmtest/rc/nasm -v
NASM version 3.02rc0 compiled on Oct 13 2025
$ ~/proj/nasmtest/rc/nasm test.asm
test.asm:2: error: symbol `aa' not defined
$