---
name: "yasm_objfmts"
section: "7"
platform: "linux"
package: "yasm"
version: "1.3.0-9"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/yasm_objfmts"
---

# yasm\_objfmts(7)

Yasm Supported Object Formats

## NAME

yasm\_objfmts - Yasm Supported Object Formats

## SYNOPSIS

**yasm** **-f** *objfmt* *...*

## DESCRIPTION

The standard Yasm distribution includes a number of modules for different object formats (Yasm's primary output).

The object format is selected on the [**yasm**(1)](/yasm/1.md) command line by use of the **-f** *objfmt* command line option.

## BIN

The “bin” object format produces a flat-format, non-relocatable binary file. It is appropriate for producing DOS .COM executables or things like boot blocks. It supports only 3 sections and those sections are written in a predefined order to the output file.

## COFF

The COFF object format is an older relocatable object format used on older Unix and compatible systems, and also (more recently) on the DJGPP development system for DOS.

## DBG

The “dbg” object format is not a “real” object format; the output file it creates simply describes the sequence of calls made to it by Yasm and the final object and symbol table information in a human-readable text format (that in a normal object format would get processed into that object format's particular binary representation). This object format is not intended for real use, but rather for debugging Yasm's internals.

## ELF

The ELF object format really comes in three flavors: “elf32” (for 32-bit targets), “elf64” (for 64-bit targets and “elfx32” (for x32 targets). ELF is a standard object format in common use on modern Unix and compatible systems (e.g. Linux, FreeBSD). ELF has complex support for relocatable and shared objects.

## MACHO

The Mach-O object format really comes in two flavors: “macho32” (for 32-bit targets) and “macho64” (for 64-bit targets). Mach-O is used as the object format on MacOS X. As Yasm currently only supports x86 and AMD64 instruction sets, it can only generate Mach-O objects for Intel-based Macs.

## RDF

The RDOFF2 object format is a simple multi-section format originally designed for NASM. It supports segment references but not WRT references. It was designed primarily for simplicity and has minimalistic headers for ease of loading and linking. A complete toolchain (linker, librarian, and loader) is distributed with NASM.

## WIN32

The Win32 object format produces object files compatible with Microsoft compilers (such as Visual C++) that target the 32-bit x86 Windows platform. The object format itself is an extended version of COFF.

## WIN64

The Win64 object format produces object files compatible with Microsoft compilers that target the 64-bit “x64” Windows platform. This format is very similar to the win32 object format, but produces 64-bit objects.

## XDF

The XDF object format is essentially a simplified version of COFF. It's a multi-section relocatable format that supports 64-bit physical and virtual addresses.

## SEE ALSO

[**yasm**(1)](/yasm/1.md), [**yasm\_arch**(7)](/yasm_arch/7.md)

## AUTHOR

**Peter Johnson** \<peter@tortall.net\>

Author.

## COPYRIGHT

Copyright © 2006 Peter Johnson\