mkCross

mkCross assembles the cross-compilation helpers for Windows and macOS.

Windows support

MinGW toolchain components are exposed through the returned environment and can be enabled in dev shells without extra project-specific setup.

aarch64 Linux support

The returned linuxAarch64 record lifts the aarch64-unknown-linux-gnu cross boilerplate out of consumer flakes:

• linuxAarch64.cc: the pkgsCross.aarch64-multiplatform stdenv cc
• linuxAarch64.pkgsCross: the full pkgsCross.aarch64-multiplatform package set (handy for buildInputs such as cross openssl/wayland)
• linuxAarch64.env: a ready-to-merge attrset with CARGO_TARGET_AARCH64_UNKNOWN_LINUX_GNU_LINKER, CC_aarch64_unknown_linux_gnu, and CXX_aarch64_unknown_linux_gnu

Merge linuxAarch64.env into a crane args set (along with CARGO_BUILD_TARGET = "aarch64-unknown-linux-gnu" and PKG_CONFIG_ALLOW_CROSS = "1") to cross-build for ARM64 Linux, or let mkCrossPackages wire it for you.

macOS support

osxcross is optional and turns on when one of these inputs is available:

• macosSdk: an already realized SDK reference
• macosSdkStorePath: explicit SDK store path, normally injected by host configuration
• macosSdkOutputHash: the SDK’s recursive output hash; pass it together with macosSdkStorePath so the SDK becomes a sandbox-mounted build input (see the warning below)
• sdkArchive: a local SDK archive path
• macosSdkEnvPath: explicit local discovery path
• MACOS_SDK: opt-in local discovery fallback when enableImpureMacosSdkEnv = true

Only one of macosSdkStorePath, sdkArchive, or macosSdk can be provided at a time. Resolution precedence is macosSdk, then macosSdkStorePath, then sdkArchive, then macosSdkEnvPath.

Pass macosSdkOutputHash with macosSdkStorePath. A bare store path carries no Nix string context, so under sandbox = true it is never bind-mounted and osxcross-clang fails with cannot find macOS SDK — with no eval-time error. The hash lets harbor-rs reconstruct the SDK as a content-addressed fixed-output derivation that resolves to the same path with context, making it a real sandbox input. See macOS SDK Initialization.

Ad-hoc signing of darwin outputs works out of the box: the osxcross toolchain provides an unprefixed codesign_allocate on PATH, so sigtool-style codesign in a postInstall needs no CODESIGN_ALLOCATE wiring. See Ad-hoc signing darwin binaries.

macosSdkEnvPath and the opt-in MACOS_SDK fallback accept a direct MacOSX<version>.sdk directory, a parent directory containing that SDK, or a supported SDK archive. Directory inputs are validated for the SDK settings file, TargetConditionals.h, and the required CoreFoundation/SystemConfiguration frameworks before osxcross is invoked.

Example

cross = harbor-rs.lib.mkCross {
  inherit pkgs system;
};

See macOS SDK Initialization for the recommended way to create and inject macosSdkStorePath from host configuration.