Multiarch Architecture Specifiers (Tuples)

This document describes the schema for representing architecture ABIs as directory names, based largely on normalized GNU triplets. The process to document the tuples in the Debian Policy and distribution independent standards is tracked in bug #664257, and the previous (abandoned) proposal can be found at Multiarch/TuplesAbandoned. For other multiarch topics, see the multiarch category.

Contents

Multiarch Architecture Specifiers (Tuples)
See also

The problem

Multiarch specifies a method of making libraries for multiple, mutually-incompatible architectures installable on a single filesystem in a manner that ensures the same binaries can be used without modification on any system. To accomplish this, we require unique identifiers for each architecture that identifies an incompatible set of libraries that we want to be co-installed. We want these identifiers to be specified in as vendor-neutral a manner as possible, to ensure we retain maximal binary compatibility across Linux distributions.

The solution: extend GNU triplets

We use normalized GNU triplets for most tuples, and extend the GNU triplet when it is ambiguous.

Multiarch names

Multiarch names are based on the instruction set architecture (ISA), operating system, and Application Binary Interface (ABI).

multiarch name	instruction set	syscall ABI	endianness	word size	description	spec documents
aarch64-linux-gnu	ARM64	linux	little	64	aarch64 Linux Platform	AAPCS64 (ARM IHI 005A)¹ ELF for the ARM 64-bit Architecture²
aarch64_be-linux-gnu	ARM64	linux	big	64	aarch64 Linux Platform	AAPCS64 (ARM IHI 005A)¹ ELF for the ARM 64-bit Architecture²
aarch64-linux-gnu_ilp32	ARM64	linux	little	32	aarch64 Linux Platform
aarch64_be-linux-gnu_ilp32	ARM64	linux	big	32	aarch64 Linux Platform
aarch64-uefi	ARM64	UEFI	little	64	UEFI AARCH64	UEFI Spec³
alpha-linux-gnu	Alpha	linux	little	64	glibc, Tru64 calling standard	Tru64 Calling Standard⁴
arc-linux-gnu	ARCv2	linux	little	32	glibc Linux hard-float	(ARC v2 ABI)⁵⁶
arm-linux-gnu	ARM	linux	little	32	Old ARM ABI	APCS (ARM DUI 0041 chapter 9)⁷
arm-linux-gnueabi	ARM	linux	little	32	ARM EABI, soft-float	AAPCS (ARM IHI 0042D)⁸ ARM GNU/Linux ABI Supplement⁹
arm-linux-gnueabihf	ARM	linux	little	32	ARM EABI, hard-float	AAPCS (ARM IHI 0042D)⁸ and XXXXX (TBD)
arm-uefi	ARM	UEFI	little	32	UEFI ARMHF	UEFI Spec³
armeb-linux-gnueabi	ARM	linux	big	32	ARM EABI, soft-float	AAPCS (ARM IHI 0042D)⁸ ARM GNU/Linux ABI Supplement⁹
armeb-linux-gnueabihf	ARM	linux	big	32	ARM EABI, hard-float	AAPCS (ARM IHI 0042D)⁸ and XXXXX (TBD)
hppa-linux-gnu	PA-RISC	linux	big	32	PA-RISC Linux 32-bit ELF	parisc-linux toolchain documents¹⁰
i386-gnu	IA-32	Hurd	little	32	Hurd/IA-32	ia32 functions calls¹¹ LSB Bug 3268¹² OS interface XXXXX undocumented
i386-linux-gnu	IA-32	linux	little	32	LSB IA32	SCO Developer Specifications¹³ Intel386 psABI¹¹ LSB Core-IA32¹⁴ LSB Bug 3268¹²
i386-kfreebsd-gnu	IA-32	FreeBSD	little	32	glibc kFreeBSD IA-32	XXXXX undocumented
i386-uefi	IA-32	UEFI	little	32	UEFI IA32	UEFI Spec³
ia64-linux-gnu	IA-64	linux	little	64	LSB IA64	Intel Itanium SysV psABI¹⁵ LSB Core-IA64¹⁶
loongarch64-linux-gnu	LoongArch LA64	linux	little	64	LoongArch64 Linux Platform LP64D ABI	LoongArch ELF psABI¹⁷
m68k-linux-gnu	MC68000	linux	big	32	m68k SysV ABI	ISBN: 978-0138776633
mips-linux-gnu	MIPS32r2+FPXX	linux	big	32	MIPS o32 ABI	MIPS psABI¹⁸¹⁹
mipsel-linux-gnu	MIPS2(MIPS32r2 soon)+FPXX	linux	little	32	MIPS o32 ABI	MIPS psABI¹⁸¹⁹
mips64-linux-gnuabin32	MIPS64r2	linux	big	32	MIPS n32 ABI	MIPSpro N32 ABI Handbook¹⁸²⁰
mips64el-linux-gnuabin32	MIPS64r2	linux	little	32	MIPS n32 ABI	MIPSpro N32 ABI Handbook¹⁸²⁰
mips64-linux-gnuabi64	MIPS64r2	linux	big	64	MIPS 64-bit ABI	MIPSpro N64 ABI Handbook¹⁸²⁰
mips64el-linux-gnuabi64	linux	MIPS64r2	little	64	MIPS 64-bit ABI	MIPSpro N64 ABI Handbook¹⁸²⁰
mipsisa32r6-linux-gnu	MIPS32r6	linux	big	32	MIPS o32 ABI	MIPS psABI¹⁸¹⁹
mipsisa32r6el-linux-gnu	linux	MIPS32r6	little	32	MIPS o32 ABI	MIPS psABI¹⁸¹⁹
mipsisa64r6-linux-gnuabin32	MIPS64r6	linux	big	32	MIPS n32 ABI	MIPSpro N32 ABI Handbook¹⁸²⁰
mipsisa64r6el-linux-gnuabin32	MIPS64r6	linux	little	32	MIPS n32 ABI	MIPSpro N32 ABI Handbook¹⁸²⁰
mipsisa64r6-linux-gnuabi64	MIPS64r6	linux	big	64	MIPS 64-bit ABI	MIPSpro N64 ABI Handbook¹⁸²⁰
mipsisa64r6el-linux-gnuabi64	linux	MIPS64r6	little	64	MIPS 64-bit ABI	MIPSpro N64 ABI Handbook¹⁸²⁰
powerpc-linux-gnu	PowerPC	linux	big	32	LSB PPC32	PowerPC psABI²¹ LSB Core-PPC32²²
powerpc-linux-gnuspe	PowerPC	linux	big	32	PowerPC e500 (SPE)	Power 32-bit ABI Supplement 1.0 Linux²³
powerpc64-linux-gnu	PowerPC	linux	big	64	LSB PPC64	64-bit PowerPC ELF psABI²⁴ LSB Core-PPC64²⁵
powerpc64le-linux-gnu	PowerPC	linux	little	64	??	??
riscv64-linux-gnu	RISC-V	linux	little	64	RV64G Linux Platform	RISC-V ELF psABI ²⁶
s390-linux-gnu	System/390	linux	big	32	LSB S390	S/390 ELF psABI²⁷ LSB Core-S390²⁸
s390x-linux-gnu	z/Architecture	linux	big	64	LSB S390X	zSeries ELF psABI²⁹ LSB Core-S390X³⁰
sh4-linux-gnu	SH-4	linux	little	32	glibc Linux SH-4 with fpu, double pervading	SH-4 Generic and Specific ABI³¹
sparc-linux-gnu	SPARC	linux	big	32	glibc Linux sparc32	SPARC psABI³²
sparc64-linux-gnu	SPARC64	linux	big	64	glibc Linux sparc64	SPARCv9 psABI³³
x86_64-gnu	x86_64	Hurd	little	64	Hurd / LSB AMD64	AMD64 psABI³⁴ LSB Core-
x86_64-kfreebsd-gnu	x86_64	FreeBSD	little	64	glibc kFreeBSD x86-64	XXXXX undocumented
x86_64-linux-gnu	x86_64	linux	little	64	LSB AMD64	AMD64 psABI³⁴ LSB Core-AMD64³⁵
x86_64-linux-gnux32	x86_64	linux	little	32	glibc Linux x32	x32-abi documents³⁶
x86_64-uefi	x86_64	UEFI	little	64	UEFI AMD64	UEFI Spec³

Architectures in Debian

Debian architecture name	status in Debian	multiarch name
alpha	EOL	alpha-linux-gnu
amd64	released	x86_64-linux-gnu
arc	planning	arc-linux-gnu
arm	EOL	arm-linux-gnu
arm64	released	aarch64-linux-gnu
arm64ilp32	none	aarch64-linux-gnu_ilp32
armel	released	arm-linux-gnueabi
armhf	released	arm-linux-gnueabihf
hppa	EOL	hppa-linux-gnu
hurd-i386	development	i386-gnu
hurd-amd64	development	x86_64-gnu
i386	released	i386-linux-gnu
ia64	EOL	ia64-linux-gnu
kfreebsd-amd64	EOL	x86_64-kfreebsd-gnu
kfreebsd-i386	EOL	i386-kfreebsd-gnu
loong64	development	loongarch64-linux-gnu
m68k	EOL	m68k-linux-gnu
mips	released	mips-linux-gnu
mipsel	released	mipsel-linux-gnu
mips64	none	mips64-linux-gnuabi64
mips64el	development	mips64el-linux-gnuabi64
mipsn32	none	mips64-linux-gnuabin32
mipsn32el	none	mips64el-linux-gnuabin32
mipsr6	none	mipsisa32r6-linux-gnu
mipsr6el	planning	mipsisa32r6el-linux-gnu
mips64r6	none	mipsisa64r6-linux-gnuabi64
mips64r6el	planning	mipsisa64r6el-linux-gnuabi64
mipsn32r6	none	mipsisa64r6-linux-gnuabin32
mipsn32r6el	none	mipsisa64r6el-linux-gnuabin32
powerpc	released	powerpc-linux-gnu
powerpcspe	development	powerpc-linux-gnuspe
ppc64	development	powerpc64-linux-gnu
ppc64el	released	powerpc64le-linux-gnu
riscv64	development	riscv64-linux-gnu
s390	EOL	s390-linux-gnu
s390x	released	s390x-linux-gnu
sh4	development	sh4-linux-gnu
sparc	released	sparc-linux-gnu
sparc64	development	sparc64-linux-gnu
uefi-amd64³⁷	cross	x86_64-uefi
uefi-arm64³⁷	cross	aarch64-uefi
uefi-armhf³⁷	cross	arm-uefi
uefi-i386³⁷	cross	i386-uefi
x32	none	x86_64-linux-gnux32

The status describes if the name is used in a (to be) released version of Debian and/or Ubuntu (release), if it is a new or abandoned port on Debian unofficial ports (port), or if it's used as a name for a Debian gcc multilib configuration (biarch).

On a Debian system with dpkg-dev installed, you can list Debian architectures with dpkg-architecture --list-known and get the Debian architecture name for a triplet with dpkg-architecture -t<triplet> -qDEB_HOST_ARCH.

uefi- debian architecture name have been choosen such as uefi-$(DEB_BUILD_ARCH) give sensible answer. The multiarch name was choosen in order to give directly the gnu triplet by using unknown as vendor (using for instance dpkg-architecture -f -A $(subst uefi-,,$(1)) -q DEB_TARGET_ARCH_CPU)-uefi)

Unsolved problems

Multiarch names can still be ambiguous if distributions use names in incompatible ways. For example, Debian armhf targets ARMv7 with VFPv3-D16 CPUs, but Raspbian (the basis for Raspberry Pi armhf) targets ARMv6 with VFPv2 CPUs, such as the Raspberry Pi 1, leading to strange run-time errors when running packages with the wrong definition of arm-linux-gnueabihf.

Why extend GNU triplets?

Earlier proposals used GNU triplets as the components of the library path. Proof-of-concept implementations ran into two distinct cases where GNU triplets could not be used effectively in a cross-distribution manner:

On IA-32, the GNU triplet varies according to the precise instruction set being targeted: e.g., i486-linux-gnu, i586-linux-gnu i686-linux-gnu. Such triplets will be inconsistent over time within a single distribution as compiler defaults are changed, let alone between distributions.
Historical note: On ARM, the canonical GNU triplet for EABI systems, whether using hard-float or soft-float, was arm-linux-gnueabi, despite the fact that hard-float and soft-float libraries use different calling conventions and can't be intermixed. The advice given by upstream GCC developers was to use the vendor field in the GNU triplet to express this difference1; however, the vendor field is private by design, making this unreliable for cross-distribution use. Work finally succeeded to push the arm-linux-gnueabihf triplet upstream, but there may still be some broken packages around for a while.

Supporting interfaces

dpkg-architecture -qDEB_HOST_MULTIARCH (on dpkg based systems).
gcc -print-multiarch (available upstream in GCC 4.9 and newer versions).
To avoid divergent embedded implementations of architecture->tuple mappings in every piece of software that wants to make use of these paths, a standard commandline tool that encapsulates this mapping should be provided, similar to the config.guess and config.sub tools that are a standard part of GNU autotools. We recommend a name of lsb_architecture for this tool.

MultiarchTuples