Hi, >> While testing the new libunwind version we came across a new type of unwind >> info inaccuracy on x86-64 RHEL6. See http://gcc.gnu.org/PR48597 for the >> details. > > Looks like there is a gcc patch that fixes this now. But it'll be a > while before distros package it. In the meanwhile libunwind will need > to deal with these types of issues.
There now appears to be a patch for all of GCC 4.[456].x, so things look positive. My feeling is that libunwind currently deals with these adequately, at least on x86-64. The omissions are not detectable in that unwind info is present and correct - just missing some info. x86-64 unw_step() loop will handle the problems by returning an error code - we default to full paranoia memory checks, but it can be turned off if someone builds on a platform not subject to the problems. I don't feel we'd need additional options, for example for fast trace. Clients can already choose full paranoia checks by using unw_step() loop, and adding them to fast trace will turn it into slow trace :-) I think the fast trace is reasonably useful as it is, as unfortunate as the crashes are. Regards, Lassi _______________________________________________ Libunwind-devel mailing list [email protected] https://lists.nongnu.org/mailman/listinfo/libunwind-devel
