Hi Gabe, I am the author of this part of the build system. SCons' support for dynamic generation of dependencies is really bad, so I had to build out the artificial targets to compensate.
Unfortunately as this work was three years ago, I don't remember all the gory details of the problems faced without the extra serializing dependencies, other than it was quite obvious and you would notice the builds not working, especially in an invocation with lots of targets across architectures (say, as in a util/regress), when the different architectures are in different build phases. If you haven't been able to reproduce it, I suspect it may no longer be an issue, as some flaws with that change specifically have been fixed (e.g. by b8c1e370f). See also the commit description for fe27f937, but I suspect you've already read it. Sorry I can't be much more helpful than that. Curtis ________________________________ From: gem5-dev <[email protected]> on behalf of Gabe Black <[email protected]> Sent: Tuesday, May 2, 2017 12:28:36 AM To: gem5 Developer List Subject: [gem5-dev] strange web of dependencies Hi folks. I was digging around in the scons stuff, and I notice a lot of artificial targets that have a complicated relationship of interdependencies and which seem to be there to serialize various steps of the build. There's a comment talking about how things are broken if a particular set of those dependencies are removed with -j settings above 1, but I wasn't able to reproduce any failure by removing them. I don't doubt there was some sort of dependency problem. I'd like to be able to reproduce it so I can remove the false dependencies, increase the parallelism of the build, and hopefully speed things up. Any hints as to how I can recreate whatever the problem was? Gabe _______________________________________________ gem5-dev mailing list [email protected] http://m5sim.org/mailman/listinfo/gem5-dev IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. _______________________________________________ gem5-dev mailing list [email protected] http://m5sim.org/mailman/listinfo/gem5-dev
