Shouldn't use SIGILL to detect NEON
| Affects | Status | Importance | Assigned to | Milestone | |
|---|---|---|---|---|---|
| x264 (Ubuntu) |
Triaged
|
Medium
|
Unassigned | ||
Bug Description
Binary package hint: x264
Hey
x264 currently uses SIGILL to test for support of NEON (and other features, on non-armel arch too); according to Dave Martin we need to disable the the "fast NEON MRC" test as
"""
this performance counter based test may not be safe across all platforms, and won't reliably give the right answer even where it doesn't SIGILL— it also requires a patched kernel; so we probably don't want it enabled in Ubuntu (unless we can use some other decision route like identifying the CPU from the contents of /proc/cpuinfo. I haven't attempted this for now.)
"""
see bug #388388 and bug #524859 (comments 6 and 7); patches:
http://
http://
Thanks,
| Loïc Minier (lool) wrote | #1 |
| Changed in x264 (Ubuntu): | |
| status: | New → Triaged |
| importance: | Undecided → Medium |
| Loïc Minier (lool) wrote | #2 |
| Dave Martin (dave-martin-arm) wrote | #3 |
| tags: | added: arm-porting-queue |
| tags: | added: bitesize |
Also, IIRC, SIGILL isn't thread safe.