test$ nasm -v
NASM version 3.01rc3 compiled on Mar  6 2026
test$ cat test.asm
        section CODE
extern label1
extern label2

%if label1 == label2
 %warning Same
%else
 %warning Not same
%endif

%if label1 != label2
 %warning Different
%else
 %warning Not different
%endif
test$ nasm -f obj test.asm
test.asm:8: warning: Not same [-w+user]
test.asm:12: warning: Different [-w+user]
test$ nasm -f elf test.asm
test.asm:8: warning: Not same [-w+user]
test.asm:12: warning: Different [-w+user]
test$ cat test2.asm
        section CODE
extern label

%if label > 26
 %warning Above
%else
 %warning Not above
%endif

%if label <= 26
 %warning Below or equal
%else
 %warning Not below or equal
%endif
test$ nasm -f obj test2.asm
test2.asm:4: error: `>': operands differ by a non-scalar
test2.asm:10: error: `<=': operands differ by a non-scalar
test$ nasm -f elf test2.asm
test2.asm:4: error: `>': operands differ by a non-scalar
test2.asm:10: error: `<=': operands differ by a non-scalar
test$ cat test3.asm
        section CODE
extern label

%assign def label
test$ nasm -f obj test3.asm
test3.asm:4: error: non-constant value given to `%assign'
test$ nasm -f elf test3.asm
test3.asm:4: error: non-constant value given to `%assign'
test$