On 29 Jul 2026, at 21:44, John Baldwin <[email protected]> wrote: > > On 7/20/26 17:51, Konstantin Belousov wrote: >> The branch main has been updated by kib: >> URL: >> https://cgit.FreeBSD.org/src/commit/?id=6e93f5e4d6932c423b89dff8fc08d86f8bdeb7b9 >> commit 6e93f5e4d6932c423b89dff8fc08d86f8bdeb7b9 >> Author: Konstantin Belousov <[email protected]> >> AuthorDate: 2026-02-13 11:24:40 +0000 >> Commit: Konstantin Belousov <[email protected]> >> CommitDate: 2026-07-20 21:51:02 +0000 >> amd64: FRED support >> FRED support as defined starting from the SDM rev. 90, requires a >> new >> 'events' entry point to receive user and kernel mode exceptions and >> interrupts notifications from the hardware. A minimal asm trampoline is >> enough, rest can be implemented in C due to the clean FRED organization >> of the event reporting. >> The syscall entry is handled by a microptimized assembly path, >> directly >> calling into the amd64_syscall() handler, instead of the generic events >> entry point. >> Tested by: emaste >> Sponsored by: The FreeBSD Foundation >> MFC after: 1 week >> Differential revision: https://reviews.freebsd.org/D55829 > > This appears to have broken the cross-build jobs on GitHub for the past week > which build with clang 15 and clang 18. Are those versions too old to support > the instructions used here? > > Sample output: > > -------------------------------------------------------------- >>>> stage 3.1: building everything > -------------------------------------------------------------- > /home/runner/work/freebsd-src/freebsd-src/sys/amd64/amd64/exception.S:1455:2: > error: invalid instruction mnemonic 'eretu' > eretu > ^~~~~ > /home/runner/work/freebsd-src/freebsd-src/sys/amd64/amd64/exception.S:1521:2: > error: invalid instruction mnemonic 'lkgs' > lkgs %ax > ^~~~ > /home/runner/work/freebsd-src/freebsd-src/sys/amd64/amd64/exception.S:1542:2: > error: invalid instruction mnemonic 'eretu' > eretu > ^~~~~ > /home/runner/work/freebsd-src/freebsd-src/sys/amd64/amd64/exception.S:1662:2: > error: invalid instruction mnemonic 'erets' > erets > ^~~~~ > /home/runner/work/freebsd-src/freebsd-src/sys/amd64/amd64/exception.S:1682:2: > error: invalid instruction mnemonic 'erets' > erets > ^~~~~ > --- exception.o --- > *** [exception.o] Error code 1 > > (Or maybe clang needs some -m<foo> or .set <foo> to enable use of these > instructions?)
LLVM 19+: https://github.com/llvm/llvm-project/commit/13b265c7b5c6a989427639e33893c158f737480b So we need compatibility defines or similar. Jessica
