How to call an label in a section while I defined it in another section in NASM?-Collection of common programming errors

section dseg
bits 16
gdt:
code_descriptor:     
.......

section cseg
bits 16
start:
    mov ax, seg dseg   

When I compile this file, it says:

error : symbol ‘dseg’ undefined.

What is wrong? And how to call the offset address of cseg?

Originally posted 2013-11-09 23:11:54.