blender: Error: Unable to deduce MP Clang version from /usr/bin/clang

[ryandesign (Ryan Carsten Schmidt)]

blender issues this error macOS 15:

Warning: All compilers are either blacklisted or unavailable; defaulting to first fallback option
Error: Unable to deduce MP Clang version from /usr/bin/clang

See also #67386.

[cjones051073 (Chris Jones)]

Blender currently blacklists all Xcode clang versions, and macports clang 16+. This vetos all compilers currently available on macOS15, so the fallback goes to something inappropriate and known to fail.

Blender should really think about updating the compiler versions it uses, as the ones it currently enforces are getting increasingly out of date and prone to issues like this.

Nevertheless, work is ongoing that might restore clang-15 to macOS15, which will, for now, resolve the problem. But blender really should update as this is bound to happen again eventually.

[markemer (Mark Anderson)]

Wow, yeah clang-15 is pretty old, which means this still breaks until 15 and 14 work (if they ever do, I know those PRs are in draft)

[markemer (Mark Anderson)]

Also, looking at blender, it's pretty out of date too - 4.2 is the current LTS, I'm pretty sure that will break on old versions of macOS but we might want to split between a modern blender and an old one.

[markemer (Mark Anderson)]

Ok, oof, I'm gonna open another ticket for modern blender, because I have been fighting it for a while - that's a heavy lift of a port.

I also had no luck building with clang-16, I think our best bet here is to wait for 15 or 14 to work since we have those in flight.

[jasonliu-- (Jason Liu)]

I have tried off and on over the past couple of years to try to get newer versions of Blender to compile, but between taking care of sick family members, trying to slowly rebuild after the complete loss of my home computing infrastructure due to a nearby lightning strike, and the rapid pace of changes in the Blender code base, means that I haven't successfully been able to get my Portfile to compile since Blender 3.0 was released.

My plan has always been to split Blender into versioned subports... there will probably always have to be a blender-2.x subport, because Blender 3 started introducing Vulkan into its code. This means that versions of macOS that don't have Metal won't be able to use MoltenVK to run Blender (i.e. anything older than 10.11 El Capitan would be stuck with blender-2.x).

[markemer (Mark Anderson)]

Replying to jasonliu--:

I have tried off and on over the past couple of years to try to get newer versions of Blender to compile, but between taking care of sick family members, trying to slowly rebuild after the complete loss of my home computing infrastructure due to a nearby lightning strike, and the rapid pace of changes in the Blender code base, means that I haven't successfully been able to get my Portfile to compile since Blender 3.0 was released.

My plan has always been to split Blender into versioned subports... there will probably always have to be a blender-2.x subport, because Blender 3 started introducing Vulkan into its code. This means that versions of macOS that don't have Metal won't be able to use MoltenVK to run Blender (i.e. anything older than 10.11 El Capitan would be stuck with blender-2.x).

Sorry to hear that - and I don't doubt it, that is a complicated portfile. I could see that from 2.93 and my fresh attempt at 4.2.2, which I wound up basically having to start from scratch on. But I agree we're gonna need blender-2 and blender-4 at least, or something like that, because 2.93 is still relevant to a lot of workflows, and the new ones wont run very far back.