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Build / bind task with nasm and ld

I have an example assembly file that I am compiling with nasm:

nasm -f elf syscall.asm

This creates the syscall.o file . I am trying to associate it with ld:

ld -o syscall syscall.o

The ld command fails with the following error:

ld: i386 architecture of input file `syscall.o' is incompatible with i386:x86-64 output

However, if I do

ld -o syscall syscall.o -melf_i386

the command succeeds and I get the syscall executable .

Finding out that nasm is not generating object code in x86-64 format, I added the "BITS 64" directive to the top of the syscall.asm file.

Then trying to build syscall.asm with nasm gave the following error:

error: elf output format does not support 64-bit code

This seems strange, because doing "file / usr / bin / nasm" on my terminal gives:

/usr/bin/nasm: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.18, stripped

My 64-bit Fedora Core 11 has the latest nasm installed, and my processor is an Intel Core 2 Duo E7200.

[EDIT]

, nasm , i386: x86-64.

+5
1

elf64 .

:

$ cat elf64.asm
section .text
        jmp [rax]
$ nasm -f elf64 elf64.asm
$ objdump -Sr elf64.o

elf64.o:     file format elf64-x86-64


Disassembly of section .text:

0000000000000000 <.text>:
   0:   ff 20                   jmpq   *(%rax)
+8

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