On Tuesday, July 31, 2018 at 10:06 AM, Paul Koning wrote: > > On Jul 31, 2018, at 12:36 PM, Mark Pizzolato <m...@infocomm.com> wrote: > > > > ... > >> Interesting, and not too surprising. Given that, it may be useful to > >> use a recent GCC which supports LTO -- Link Time Optimization. > >> That's a scheme that allows whole-program optimization, rather than > >> the normal per-sourcefile optimization. > > > > LTO was actually the default for most environments a few years back, > > but I think that was one of the first things that broke some > > simulators on some platforms. It has been backed out when there were > problems. > > If that's still true with the latest GCC, especially with the in-development > one > (V9.0, from Subversion), those issues might be undefined code problems in > SIMH. It is of course also possible that they are LTO bugs, in which case > finding > and reporting them would be a useful thing.
The preponderance of issues are undefined code problems. Given these being pervasive, chasing down corner case problems that LTO might cause (and identifying the actual details) hasn't been on the radar. Being able to rigorously verify the reworked VAX code (and fix remaining or newly introduced issues) would be a priority given the right tools. I hope to hear back from Tim's contact to further this project. Thanks. - Mark _______________________________________________ Simh mailing list Simh@trailing-edge.com http://mailman.trailing-edge.com/mailman/listinfo/simh
