$ nasm -v
NASM version 2.16rc0 compiled on Dec 28 2020
$ cat test1.asm
%strcat foo "bar","baz"
%warning foo
$ nasm test1.asm
test1.asm:1: error: non-string passed to `%strcat': ,
$ cat test2.asm
%strcat foo "bar" "baz"
%warning foo
$ nasm test2.asm
test2.asm:2: warning: barbaz [-w+user]
$ oldnasm -v
NASM version 2.14.03rc2 compiled on Aug 31 2019
$ oldnasm test1.asm
test1.asm:2: warning: barbaz [-w+user]
$ oldnasm test2.asm
test2.asm:2: warning: barbaz [-w+user]
$
nasm-2.15.05-113-gdc4a6194