The wiki page has some neat details on this https://en.m.wikipedia.org/wiki/Mac_68k_emulator
> On Jun 10, 2020, at 9:49 PM, Robert Engels <reng...@ix.netcom.com> wrote: > > Yep. My timeline/memory was wrong. It was the 68k to PowerPC. Intel required > dual binaries. Thanks for the correction. > >> On Jun 10, 2020, at 8:26 PM, David Riley <fraveyd...@gmail.com> wrote: >> >> Not quite. When they switched to PowerPC, that was the case; the initial >> one was a table-driven instruction translator in ROM originally written for >> the M88k, which had been the original target before Motorola canned it, but >> it was apparently a relatively simple thing to change the translations to >> PowerPC instructions (only took a weekend according to legend, but, well, >> legends). It eventually evolved into something much more sophisticated and >> performant. >> >> The transition from PowerPC to Intel ended the Classic VM environment that >> ran Mac OS 9, which included the old 68k translator in the ROM file. On a >> PowerPC Mac running OS X 10.4 (including G5s, which are 64-bit!), you can >> run 68k apps from the dark ages just fine (as long as they didn't use >> undocumented interfaces, etc). I've been doing exactly this recently while >> porting a very old Mac game to modern systems. >> >> Anyway, no Classic support on Intel, thus no 68k either (and PowerPC only >> for OS X apps). The PowerPC emulation for Intel (Apple called it "Rosetta") >> was a licensed third-party product that used JIT-style compilation, but it >> really only worked for userland programs; it didn't support drivers and it >> presumably wasn't close enough to the real deal to support the Classic >> environment, so they dropped it in all Intel versions of Mac OS (10.5 >> dropped it for PowerPC as well for reasons I don't quite understand, since >> that was the last PowerPC version). >> >> Anyway, given that the PowerPC translation on Intel only lasted through >> 10.6, and Apple just dropped 32-bit Intel support in 10.15, I would expect >> backwards compatibility support for Intel apps (if they're even planning it) >> to drop within 2-3 revisions of macOS after the transition. Just putting >> that out there. >> >>>> On Jun 10, 2020, at 8:47 PM, Robert Engels <reng...@ix.netcom.com> wrote: >>> >>> When Macs first switched to Intel the OS included a Motorola 68k emulator >>> so that existing Mac binaries would run. >> -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/E186B60B-1F4E-4049-BDE9-7A0094E8ED3C%40ix.netcom.com.
