> But, it’s good to know Mach-O was designed to support multi-arch binaries since the PowerPC-to-Intel transition (yay, mac history!) and now Intel-to-ARM transitions if we pretend that didn’t happen like three years ago.
Fat binaries predate the PowerPC-to-Intel transition. They were used at NeXT to support a quite wide variety of hardware platforms, and were even used publicly in the "pure" PowerPC Mac era for... reasons that I encourage someone to dig into, but am not sure are fully disclosed.
The PowerPC wasn't a static ISA, with later revs adding features like Altivec and 64-bit mode, back in the, like, G4 and G5 era. Thus, the day binaries were used to ship a single fat binary that had versions with and without Altivec optimizations enabled.
Anybody still have a G5 cube?