Differential D23937
amd64 atomics: guard flag output operand use with feature test Authored by rlibby on Mar 3 2020, 6:58 AM.
Details Allow old cross compilers to build base after r358439 & r358440. To be honest, I'm not sure what the best direction here is. Options
Requested by: melifaro kyua test -k /usr/tests/sys/Kyuafile Manual inspection of generated code.
Diff Detail
Event TimelineComment Actions I think this is too much of an uglifier. Given this and the fact that the change is -CURRENT only (i.e., not going to be MFCed) I think looking out for older compilers is not worth it. I don't see a clear fix modulo copy-pasting the current routines and ifdefing around them. The guarantee is that stable/12 can build -CURRENT but that is supposed to start with updating the toolchain thus it should not be a problem. One can sanity check that this is maintained. Comment Actions I believe this is overreaction and we should select no. 2, ie. do nothing. Note that 12 has clang 9.0.1, 12.1 has 9.0 (from my memory), and 11 is on 8.0.1, might be 9.0.1. Comment Actions Okay, I am happiest to go with option #2 also. I'll leave this up for a little in case any one else has a comment. This did cause one problem in practice. A port had pinned itself to llvm 7.0, and then failed to build because of this (a kernel module I think): Obviously the right solution is for the port to fix the bug instead of pin the compiler version, but anyway this is the closest to a real scenario that I know. |