On 01/01/2017 11:23 PM, eddie_cottongim eddie_cottongim wrote: > I realize this is probably a bad idea for many reasons, and likely a dead end > at some point, as low level support has been dropped at some point in the > kernel > and it appears to have problems in gcc. But maybe a leap forward of 5-10 > years is possible.
One problem with SPARCv8 (which this machine type uses) is that it does not support the compare-and-swap instruction (CAS) which means that lock-free atomics are not possible on these machines. However, lock-free atomics are required for proper C++11 support. Thus, when you compile gcc on SPARC with anything older than v9, you will not be able to use std::future which also a problem Debian's armel port is facing and which is one of the reasons why the port is most likely going to be removed from Debian 10 (Codename: Buster) [1]. There are ways to emulate these atomics with helper functions in the kernel [2], however, I don't know how much effort it is and you probably need more than one active porter to achieve this. Adrian > [1] https://lists.debian.org/debian-devel/2016/12/msg00141.html > [2] https://stuff.mit.edu/afs/sipb/contrib/linux/Documentation/atomic_ops.txt -- .''`. John Paul Adrian Glaubitz : :' : Debian Developer - [email protected] `. `' Freie Universitaet Berlin - [email protected] `- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913
