While the iOS Simulator does share the host kernel it does not share libraries. It is effectively a separate userspace, with its own launchd_sim, its own mach b

While the iOS Simulator does share the host kernel it does not share libraries. It is effectively a separate userspace, with its own launchd_sim, its own mach bootstrap namespace, and so on. The only exception to that is libsystem_{pthread,kernel,platform} because those form the kernel's ABI boundary. Libraries like libc, libdispatch, et al are the iOS build and use the iOS ABI.