On Sat, 27 Jun 2026 14:49:32 GMT, Yasumasa Suenaga <[email protected]> wrote:
>> Yes, it looks like _pac_mask was added specifically for SA by >> [JDK-8286711](https://bugs.openjdk.org/browse/JDK-8286711). >> >> What happens if the core was generated on a machine with PAC support but >> debugged on a machine without it. Is _pac_mask going to be setup in that >> case? > >> What happens if the core was generated on a machine with PAC support but >> debugged on a machine without it. Is _pac_mask going to be setup in that >> case? > > `_pac_mask` would be exposed via VMStructs, so we can use it in SA when we > attach the core. Then we can unwind call stacks on PAC-disabled machine. > > For unwinding, we need to restore caller PC by AND operation with > `_pac_mask`. So it is ok to know just `_pac_mask` as a bitmask. But if PAC is disabled on the machine that SA is running on then _pac_mask won't be setup. This means you won't be able to do the AND operation to restore the caller PC. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/31669#discussion_r3486500996
