nasm displaying a dword with printf

Question

this is my code (test.asm)

expected "num = 1337"

output: "num = 4199373"

question: How do I fix it.

intent: curiosity towards assembly language, not assignment.

; nasm -fwin32 test.asm
; gcc test.obj -o test
    extern _printf
    global _main

    section .text
_main:
    push num
    push msg
    call _printf
    add esp, 8
    ret

msg db 'num = %i', 0xa, 0
num dd 1337

changing push num to push dword [num] fixed it.

score 3 · Accepted Answer · answered Mar 06 '13 at 20:45

3

push num pushes the address of num (similar to push msg), but not the value contained there.

You need push dword [num] instead.

answered Mar 06 '13 at 20:45

Alexey Frunze

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NASM's COFF is not Microsoft's PE-COFF. NASM's COFF is the same as COFF supported by DJGPP gcc. – Alexey Frunze Mar 06 '13 at 20:55

nasm displaying a dword with printf

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