Error comma colon decorator or end of line expected after operand

Syntactically, using NASM, there is no PTR keyword. Removing those allows the code to compile up to the undefined ___main. For example:

push    ebp
mov     ebp, esp
and     esp, -16
sub     esp, 16
call    ___main:     ; semi-colon starts comment (should be colon)
mov     DWORD [esp+12], 753664
mov     eax, DWORD [esp+12]
mov     BYTE [eax], 65
leave
ret

Then compiling with:

$ nasm -felf -o asm_recompile.o asm_recompile.asm

The only error returned is:

asm_recompile.asm:5: error: symbol `___main' undefined

Generally, NASM assembly programs require:

section .text
    global _start

    _start:

Note: Just because you compile to assembly with gcc, do not expect to be able to simply compile the code back to a working elf executable using NASM. gcc by default generates AT&T syntax that is incompatible with NASM. Even telling gcc to output assembly using the -masm=intel option to produce intel format assembly will not compile as-is in NASM. gcc uses as as the assembler. You will have varying luck using as as well, due to the myriad of compiler scripts and options gcc uses by default. The best examination of the process you can get with gcc is to compile your c program to executable using the -v, --verbose option. That will show all of the compiler commands gcc uses to generate the assembly associated with the c code.

Здравствуйте, я только начинаю изучать ассемблер. Есть код программы, пытаюсь его скомпилировать:

.model tiny
.286
.data
msg db  'Hello World11111111111111111111111111111111111111111111111111111111'
position    word    0312h
color   db  03dh
count   word    0043h
.code
 
org 100h
 
start:
    call    clrscr
    mov ax, 0   ;word
    mov ax, 1300h
    mov bp, offset msg
    mov cx, count
    mov dx, position
    mov bl, color
    int 10h
 
    mov ah, 02h
    mov dx, position
    sub dx, 0101h
    int 10h
    mov ah, 09h
    mov al, 0c9h
    mov cx, 1
    int 10h
 
    mov ah, 02h
    inc dx
    int 10h 
    mov ah, 09h
    mov al, 0cdh
    mov cx, count
    int 10h
 
    add dx, count
    mov ah, 02h
    int 10h
    mov ah, 09h
    mov al, 0bbh
    mov cx, 1
    int 10h
 
    mov ah, 02h
    add dx, 0100h
    int 10h
    mov ah, 09h
    mov al, 0bah
    mov cx, 1
    int 10h
 
    mov ah, 02h
    sub dx, count
    dec dx
    int 10h
    mov ah, 09h
    int 10h
 
    mov ah, 02h
    add dx, 0100h
    int 10h
    mov ah, 09h
    mov al, 0c8h
    int 10h
    
    mov ah, 02h
    inc dx
    int 10h
    mov ah, 09h
    mov al, 0cdh
    mov cx, count
    int 10h
    
    mov ah, 02h
    add dx, count
    int 10h
    mov ah, 09h
    mov al, 0bch
    mov cx, 01h
    int 10h
 
    mov ah, 02h
    mov dx, 1801h
    int 10h
    int 20h
        
clrscr:
    mov ah, 0h
    mov al, 03h
    int 10h
    ret
end start

Компилирую командой:
nasm -f bin first.asm -o first.com

Получаю следующие ошибки:

D:Assembler>nasm -f bin first.asm -o first.com
first.asm:1: error: attempt to define a local label before any non-local labels
first.asm:1: error: parser: instruction expected
first.asm:2: warning: label alone on a line without a colon might be in error [-w+orphan-labels]
first.asm:2: error: attempt to define a local label before any non-local labels
first.asm:3: warning: label alone on a line without a colon might be in error [-w+orphan-labels]
first.asm:3: error: attempt to define a local label before any non-local labels
first.asm:5: error: parser: instruction expected
first.asm:7: error: parser: instruction expected
first.asm:8: warning: label alone on a line without a colon might be in error [-w+orphan-labels]
first.asm:16: error: comma, colon, decorator or end of line expected after operand
first.asm:95: error: parser: instruction expected

Мои знакомые просто как-то переносят этот код в DoxBOX и там у них всё прекрасно работает. Подскажите пожалуйста как можно исправить код программы, чтобы он правильно компилировался NASM-ом. Спасибо.

Issue

I am programming in c and i compiled a c code to assembly code but when i re-compile the code with the NASM assembler , it is giving me a error

Expected comma , colon , decorator or end of line expected after operand . This occurs in
line number 6 , line number 7 and 8 . Please help me with this .

push    ebp
mov     ebp, esp
and     esp, -16
sub     esp, 16
call    ___main ;
mov     DWORD PTR [esp+12], 753664
mov     eax, DWORD PTR [esp+12]
mov     BYTE PTR [eax], 65
leave
ret

Thanks,

Solution

Syntactically, using NASM, there is no PTR keyword. Removing those allows the code to compile up to the undefined ___main. For example:

push    ebp
mov     ebp, esp
and     esp, -16
sub     esp, 16
call    ___main:     ; semi-colon starts comment (should be colon)
mov     DWORD [esp+12], 753664
mov     eax, DWORD [esp+12]
mov     BYTE [eax], 65
leave
ret

Then compiling with:

$ nasm -felf -o asm_recompile.o asm_recompile.asm

The only error returned is:

asm_recompile.asm:5: error: symbol `___main' undefined

Generally, NASM assembly programs require:

section .text
    global _start

    _start:

Note: Just because you compile to assembly with gcc, do not expect to be able to simply compile the code back to a working elf executable using NASM. gcc by default generates AT&T syntax that is incompatible with NASM. Even telling gcc to output assembly using the -masm=intel option to produce intel format assembly will not compile as-is in NASM. gcc uses as as the assembler. You will have varying luck using as as well, due to the myriad of compiler scripts and options gcc uses by default. The best examination of the process you can get with gcc is to compile your c program to executable using the -v, --verbose option. That will show all of the compiler commands gcc uses to generate the assembly associated with the c code.

Answered By — David C. Rankin

Compilation problem following examples #312

Hi,
I’m trying to follow the fuzzing example for libjpeg-turbo (https://github.com/google/honggfuzz/tree/master/examples/libjpeg), and it appears to fail at compiling libjpeg using honggfuzz’s compilers. Below are the steps I used and the errors the makefile gives.

1. Compiled hongfuzz
2. Got libjpeg-turbo source with $apt-get source libjpeg-turbo
3. Got required tools to config with $sudo apt-get install autoconf libtool nasm
4. Run $autoreconf because of an automake version mismatch error when trying to config libjpeg-turbo. Autoreconf fixes it.
5. Configured libjpeg-turbo with CC=../honggfuzz/hfuzz_cc/hfuzz-clang CXX=../honggfuzz/hfuzz_cc/hfuzz-clang++ CFLAGS=»-fsanitize=address» ./configure
6. Run $make -j$(nproc)

As far as I can tell, the «ignoring unknown tag NASM» error should not cause issues, but the other errors seem to be syntax-related. Honggfuzz’s compiler seems to see a lot of «comma, colon, decorator or end of line expected after operand», «symbol not defined before use», and «unable to multiply two non-scalar objects» errors.

I’ve compiled libjpeg-turbo using AFL’s compilers before, and AFL seems to compile with no issues, so this can’t be a problem with libjpeg-turbo.

What can I do to compile libjpeg-turbo with Honggfuzz’s instrumentation? Any help is appreciated.

The text was updated successfully, but these errors were encountered:

Источник

Анализ ошибок NASM, ожидается инструкция

Я задал похожий вопрос здесь но я сменил ассемблеры, и вопрос почти полностью изменился, поэтому, чтобы избежать беспорядка, я публикую совершенно новый вопрос. Короче говоря, у меня Windows 7, я только что установил NASM и пытаюсь собрать листинг кода из книги Майкла Абраша под названием Zen of Assembly. Вот код листинга:

Я добавил nasm.exe в свой путь, сохранил этот файл как listing1.asm и попытался использовать следующую команду CMD для его сборки:

Однако он не собрался и вместо этого выдал следующие ошибки:

Не знаю, что мне здесь делать; Я пытался немного погуглить, но ничего не придумал. Кто-нибудь признает эти ошибки?

задан 20 июля ’12, 04:07

Это код для старой доброй MS-DOS. Он не будет работать под Windows 7, где вам не разрешено перенастраивать оборудование из пользовательской программы. — Bo Persson

1 ответы

Этот язык ассемблера — MASM, а не NASM.

Во-первых, сегменты NASM определяются по-разному.

И это заявление «ПРЕДПОЛАГАЕТ». У вас, должно быть, есть древняя книга. Это старый, старый код MASM. Навевает воспоминания о начале 1980-х!

Между NASM и MASM есть много различий, и ваш код требует немалой работы для переноса. Если вы хотите перенести этот код MASM на NASM, см. MASM / NASM Различия или документацию по NASM или погуглите «NASM vs MASM»

TL;DR: вы пишете код MASM, а не NASM.

ответ дан 23 мая ’17, 12:05

Большое спасибо, именно то, что я искал. — Линкольн Бергесон

Не тот ответ, который вы ищете? Просмотрите другие вопросы с метками assembly x86 nasm or задайте свой вопрос.

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I am trying to reassemble code reversed from an executable using radare2. I have managed to extract the asm and am using nasm for reassembling.

The question is, the code also contains commands like
byte ptr [esi],pushal, fucomi st(3) and sqrtps xmm5, xmmword [edx - 1] which I’m unfamiliar with.

I tried assembling with the nasm -felf -o command. However, I’m getting the following errors.

test.asm:68: error: comma, colon, decorator or end of line expected after operand
test.asm:69: error: comma, colon, decorator or end of line expected after operand
test.asm:85: error: comma, colon, decorator or end of line expected after operand
test.asm:133: error: comma, colon, decorator or end of line expected after operand
test.asm:167: error: impossible combination of address sizes
test.asm:167: error: invalid effective address
test.asm:298: error: symbol `pushal' redefined
test.asm:423: error: comma, colon, decorator or end of line expected after operand
test.asm:637: error: comma, colon, decorator or end of line expected after operand
test.asm:802: error: symbol `pushal' redefined

According to this stackoverflow post, the keyword ptr does not exist in nasm and it suggested that the word be removed. Doing that resolved a few errors. Now I have the following errors:

test.asm:68: error: comma, colon, decorator or end of line expected after operand
test.asm:69: error: comma, colon, decorator or end of line expected after operand
test.asm:85: error: comma, colon, decorator or end of line expected after operand
test.asm:133: error: comma, colon, decorator or end of line expected after operand
test.asm:298: error: symbol `pushal' redefined
test.asm:423: error: comma, colon, decorator or end of line expected after operand
test.asm:637: error: comma, colon, decorator or end of line expected after operand
test.asm:802: error: symbol `pushal' redefined

Since I have no idea what pushal and sqrtps mean, I’m reluctant to remove them from the code. Could someone please explain what these commands mean?

Additionally suggestions on how I can get this as a compilable error-free code are also welcome.

EDIT:
Following user blabb s suggestion, i replaced pushal with pushad and now I have only 2 errors

test.asm:80: error: comma, colon, decorator or end of line expected after operand
test.asm:127: error: comma, colon, decorator or end of line expected after operand

The 2 lines in question are:

fucomi st(3)
and
sqrtps xmm5, xmmword [edx - 1]

any suggestions as to how to handle this?

EDIT 2:
including lines 76-83

pop esi
int3
sti
xor ebx,ebx
fucomi st(0),st(3)
jmp 0x400299
pop es
xor ebx, ebx

and lines 122-132

add cl, bh
iretd
mov dr0, ebx
and eax, ebx
ret
push 0xf
sqrtps xmm5, xmmword [edx - 1]
push ecx
push 0xffffffffffffffff
call dword [ecx + 0x51]
push ecx

EDIT3:
Based on user blabb s suggestion and also by referring the NASM docs, I found that NASM does not accept st(0),st(3) and instead it accepts st0,st3. Now only one error left.

test.asm:127: error: comma, colon, decorator or end of line expected after operand

Still did not understand how to handle this.