> > Also, multilib for aarch64 + armv7hl is not "A Thing" (TM), IIRC > > because no aarch64 hardware really supports that. > > > > There is hardware that does support it, but we pretend they don't > exist in Fedora. After all, the Raspberry Pi is an example of this. No, there's HW that will run in ARMv7 mode or aarch64 mode but not always at the same time, for example you use you have to set a flag in the config.txt so it will run in aarch64 mode when it boots. The architectures are also not compatible, in the case of x86_64 it's a super set of x86 adding 64bit instructions as an extension to the 32 bit architecture so 32bit is guaranteed to be there when you have an x86_64 chip where on Arm they are two bits of silicon on the same chip, the ISA is different and the 64 bit architecture isn't a superset of the 32 bit architecture. On a ARMv8 chip the 32 bit silicon is optional, some silicon vendors, such as the SoCs in the Raspberry Pi 3 and 4 have it but there's a lot that don't, and newer gens of chips will even reduce this more. So while there are some that can run both 32 bit and 64 bit code side by side it's not multilib in the traditional x86 sense where they run side by side because the instructions are the same and can be queued to run on the same silicon. There is no way to tell until the code tries to run whether the chip is capable of this so you could use a aarch64 bit dnf/rpm stack to install ARMv7 binaries only to have them fail when you try to run them (or in rpm post install scripts) which gives a terrible experience. Or if you have a VM that migrates from one platform to another which doesn't support it and things start to break. The multilib support, even in x86, is pretty glued together with exceptions all over the place, so the cost vs benefit of actually supporting this in any level of sane manner was considered not worth it. Peter _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx
