[epcoa]

That it was a failure is well known. But fringe, as in obscure (which is what I think is salient in this context)? I think that is misleading - that it has an official gcc backend to remove is a sufficient counterargument. Funny you mentioned PA-RISC and Alpha, as both were abandoned by HP and Compaq for it. Stupid (at least HP did backpedal, but not after burning a mountain of cash, it was to replace the PA), but not consistent with fringe. Getting it into the Linux kernel and gcc support was a big deal at the time thousands of man-hours were expended on all of this, all the investment and work was done for the dominant architecture. Obviously Microsoft was hugely invested in it, but some there thankfully had better ideas and didn’t miss the x86-64 boat, since it already stank years prior to its release. DEC Alpha was also in the long run a commercial failure. wouldn't call it fringe though. PA-RISC was commercially middling, I also wouldn't call it fringe (both shitcanned for Itanic BTW, for which people are still bitter).

[brucehoult]

Well-known, yes, but fringe as in seldom seen.

Absolutely correct that mega-millions or billions went into it, both hardware and software, and that it FUD'ed many other ISAs to premature extinction.

It's not that hard to get an ISA into gcc and Linux -- you just need shipping hardware (or a convincing story that there will be) and someone to do the work. For example Andes (Taiwan) and C-Sky (China) both got their proprietary ISAs (nds32, c-sky) into GCC and the Linux kernel. And both switched to RISC-V not long after :_)

[epcoa]

Ok I’ll concede that’s a graveyard of obscurity in the gcc tree, but some group of people thought each one of those were worth the effort at some point, possibly delusionally. Do you need shipping hardware even? MMIX has a backend. Itanium doesn’t deserve this label though, shall it live forever in infamy.