On Mon, Nov 30, 2015 at 12:34 AM, Matthias Klose <d...@ubuntu.com> wrote: > The attached patch avoids building the non-default multilib and libstdc++-v3 > debug builds in bootstrap builds during bootstrap builds, resulting in some > speedup for bootstrap builds for targets with multilibs enabled. On > x86_64-linux-gnu with 64/32/x32 multilibs enabled and the libstdc++ debug > build enabled the bootstrap with -j8 takes 34:10 without, and with the patch > 26:55, making the build ~20% faster (standard languages plus go enabled). > It's faster because it avoids the rather sequential libcc/libstdc++/libgomp > configury during stage1 and stage2. The gain by not building the libstdc++ > debug library is not that measurable, the config is copied, there is no > separate configure run. Is relying on stage_current/stage_final the correct > approach? Should that be enabled using a configure option, or by default?
I think the more natural way would be to bootstrap the host libstdc++ and only build the target libstdc++ for all multilibs. Richard. > Matthias >
