Cross compile on x64 on Darwin

[patnebe]

Context

• xcompilation support

Changes

• Add toolchain

Test Plan

• Will attempt to build on a Darwin host and try to run the binary on an x64 VM running in Qemu

[Copilot]

Pull Request Overview

This PR adds cross-compilation support for x64 architecture on Darwin hosts. The changes enable building binaries for x86_64 architecture that can be tested on virtual machines.

• Adds a CMake toolchain file for x64 cross-compilation
• Updates the Makefile to support x64 build and test targets
• Enables building and testing x64 binaries on Darwin hosts

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
toolchain_x64.cmake	New CMake toolchain file specifying Darwin as host OS and x86_64 as target architecture
Makefile	Adds build-x64, clean-build-x64, and test_x64 targets for cross-compilation workflow

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[Copilot]

CMAKE_SYSTEM_NAME should specify the target OS, not the host OS. For cross-compilation to x64, this should be set to the target operating system (e.g., Linux, Windows) rather than Darwin which is the host.

Suggested change

	set(CMAKE_SYSTEM_NAME Darwin) # Host OS
	set(CMAKE_SYSTEM_NAME Darwin) # Target OS (macOS)