#linkers

MEP-42 Linker and Runtime Recommendation

§1 Phase 1 recommendation Use LLD as the universal linker, with platform-aware overrides: ld.lld on Linux, the system ld (ld_prime) on macOS, lld-link on Windows. Bundle LLD inside the Mochi distribution (Apache 2 + LLVM exception license, one binary covers all four formats: ELF, Mach-O, PE, Wasm) so cross-host builds work from any developer machine. For the C runtime, use the host glibc on Linux (dynamic link, document the glibc-2.31...

Skipping the Linker Entirely

§1 Provenance Go internal linker: https://github.com/golang/go/tree/master/src/cmd/link Zig self-hosted backends: https://ziglang.org/devlog/2025/ Zig linker source layout: https://github.com/ziglang/zig/tree/master/src/link LLD as a library API: lld::elf::link() , lld::macho::link() , lld::coff::link() , lld::wasm::link() at https://github.com/llvm/llvm-project/tree/main/lld/include/lld/Common "Mostly statically linked" Go binary mechanism (debug/elf, debug/macho, debug/pe writers in the standard library): https://pkg.go.dev/debug/elf Authors are language toolchain authors: the Go team (Russ Cox, Cherry Mui, Than McIntosh on linker), the Zig team (Andrew Kelley, Jakub Konka), and the Wild...

GNU ld (bfd) and gold

§1 Provenance GNU binutils home: https://www.gnu.org/software/binutils/ Source and ChangeLog: https://sourceware.org/git/binutils-gdb.git Binutils 2.44 release announcement (February 2025): https://lists.gnu.org/archive/html/info-gnu/2025-02/msg00001.html gold Wikipedia entry: https://en.wikipedia.org/wiki/Gold_(linker) License: GPLv3 (with binary GPLv2-compatible link exemption for certain libraries). Maintainer: Nick Clifton (Red Hat) leads binutils. gold was originally Ian Lance Taylor's project at Google. §2 Mechanism / function Two distinct linkers ship in the GNU binutils family: ld.bfd is the classical GNU linker. It is built on...

Apple's New Linker (ld_prime / ld_new)

§1 Provenance Apple toolchain (closed source for the new linker). The older ld64 is at https://github.com/apple-oss-distributions/ld64 but Apple has not released source for ld_prime / ld_new (confirmed by community probing of opensource.apple.com, see https://developer.apple.com/forums/thread/749558) . WWDC 2023 session that introduced the new linker: "Meet mergeable libraries" (session 10268, https://developer.apple.com/videos/play/wwdc2023/10268/) . Community write-ups: Wade Tregaskis's ld_prime series at https://wadetregaskis.com/tags/ld_prime/ . "The new linker in Xcode 15" talk by Yuta Saito (kateinoigakukun):...

mold: The Modern Linker

§1 Provenance Project home and source: https://github.com/rui314/mold Author: Rui Ueyama (also the original author of LLD). Commercial vehicle: Blue Whale Systems PTE LTD (Tokyo / Singapore). License: MIT (since mold 2.0, October 2023). The earlier AGPL plus commercial dual-license was retired (see https://www.phoronix.com/news/Mold-2.0-Linker) . Slides and design background: https://easybuild.io/tech-talks/006_mold_slides.pdf §2 Mechanism / function mold is an ELF-only linker that targets the same role as ld.bfd , ld.gold , and ld.lld...

LLD: The LLVM Linker

§1 Provenance Project home: https://lld.llvm.org/ Source tree: https://github.com/llvm/llvm-project/tree/main/lld Release notes (20.1.0): https://releases.llvm.org/20.1.0/tools/lld/docs/ReleaseNotes.html License: Apache 2.0 with LLVM exception (SPDX Apache-2.0 WITH LLVM-exception ). Lead maintainers (ELF port): Fangrui Song (MaskRay), Igor Kudrin, Peter Smith. The COFF port is led by Martin Storsjo and Reid Kleckner. Apple, Sony, ARM, Google, and the broader LLVM community all contribute. LLD ships as part of the LLVM monorepo and inherits LLVM's release cadence (approximately...

Linkers