Good points; though I admit, I was thinking more Linux-capable/"Linux-class" cores in the mid-range FPGAs which is where I spend a bunch of my time. For that, t

Good points; though I admit, I was thinking more Linux-capable/"Linux-class" cores in the mid-range FPGAs which is where I spend a bunch of my time. For that, the paltry cache sizes due to limited amounts of BRAM are more noticeable (especially when other features may compete for them) so minimizing icache footprint as much as possible is win. Admittedly that's probably a marginal case versus the tiny softcores you mention; workloads that need high performance cores will practically be better off running on attached ARM processors or whatever. Anyway, all that aside, I personally wouldn't be sad to see the C extensions go away. I'm actively designing a RISC-V core for a small game console, and probably won't implement them, and will spend the time on more DV instead. I don't expect them to have any meaningful benefits for my case and mostly increase frontend complexity.