On Tue, Oct 18, 2016 at 2:35 PM, Ximin Luo <infini...@pwned.gg> wrote: > Richard Biener: >> On Mon, Oct 17, 2016 at 11:44 PM, Mike Stump <mikest...@comcast.net> wrote: >>> On Oct 17, 2016, at 2:38 PM, Ximin Luo <infini...@pwned.gg> wrote: >>>> >>>> Mike Stump: >>>>> On Oct 17, 2016, at 11:00 AM, Ximin Luo <infini...@pwned.gg> wrote: >>>>>> Therefore, it is better to emit it in all circumstances, in case the >>>>>> reader needs to know what the working >>>>>> directory was at compile-time. >>>>> >>>>> I can't help but wonder if this would break ccache some? >>>>> >>>> >>>> Could you explain this in some more detail? At the moment, GCC will >>>> already emit DW_AT_name with an absolute path (in the scenario that this >>>> patch is relevant to). How does ccache work around this at the moment? >>>> (Does it use debug-prefix-map? In which case, this also affects >>>> DW_AT_comp_dir, so my patch should be fine.) >>> >>> If you compile the same file, but in a different directory, I wonder if cwd >>> will cause the cache entry to not be reused. >>> >>> I expect one of the ccache people that are around would just know if it >>> will care at all. >> >> I believe ccache compares preprocessed source, definitely _not_ DWARF >> output, so this shouldn't break anything there. >> It might result in different object file output but as the reporter >> figured due to a bug in dwarf2out.c we end up generating >> DW_AT_comp_dir in almost all cases already. >> >> I think the patch is ok but it misses a ChangeLog entry. How did you >> test the patch? (bootstrapped and tested on ...?) >> > > Thanks, I'll add the Changelog entry. My computer isn't very powerful, so I > didn't bootstrap it yet, I only tested it on a stage1 compiler, on Debian > testing/unstable. I'll find some time to bootstrap it and test it fully over > the next few days. > > Shall I also get rid of the Darwin force_at_comp_dir stuff? Looking into it a > bit more, my patch basically obsoletes the need for this so I can delete that > as well.
That would be nice. Richard. > X > > -- > GPG: ed25519/56034877E1F87C35 > GPG: rsa4096/1318EFAC5FBBDBCE > https://github.com/infinity0/pubkeys.git
