x86 - What is wrong with this assembly code? -


it says invalid combination of opcode , operands

section .data     name:      db "what name?"     name_l:     equ $-name     hello:     db "hello"     hello_l:     equ $-hello section .bss     name_v     resb 255    section .test       global _start: _start:      mov eax, 4     mov eax, 1     mov ecx, name     mov edx, name_l     int 80h     mov eax, 3     mov ebx, 0     mov ecx, name_v     mov edx, 255     int 80h     int eax, 4     mov ebx, 1     mov ecx, hello     mov edx, hello_l     int 80h     mov eax, 4     mov ebx, 1     mov ecx, name_v     mov edx, 255     int 80h     mov eax, 1     mov eax, 0     int 80h

well, normally, assembler tell line offending one, , should examine opcode , operands ensure compatibility (or, @ minimum, let us know line is).

in meantime, have either incorrect or superfluous code in program after _start:

mov eax, 4 mov eax, 1 ; should ebx

if these linux calls, you're lucky didn't assemble. passing random length sys_write going cause sorts of grief :-) passing random exit value sys_exit not advised:

mov eax, 1 mov eax, 0 ; should ebx int 80h

and certain want text (code) section called test?

you go long way toward making code readable using equ values rather magic numbers , adding comments:

fn_exit    equ 0 fb_read    equ 3 fn_write   equ 4 : mov eax, fn_write      ; write  mov ebx, 1             ;  stdout (fd 1) mov ecx, name          ;  text write mov edx, name_l        ;  length of text write

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