On Sat, Jul 16, 2016 at 4:27 AM, Andreas Schwab <sch...@linux-m68k.org> wrote: > Andrew Pinski <pins...@gmail.com> writes: > >> On Fri, Jul 15, 2016 at 6:46 PM, Patrick Palka <patr...@parcs.ath.cx> wrote: >>> The build step that invokes "ranlib libbackend.a" (which immediately >>> follows the invocation of "ar rc libbackend.a ...") takes over 7 seconds >>> on my machine and causes the entire 450MB archive to be rewritten. By >>> instead making the build system use ar rcs -- so that the archive and >>> its index are built at once -- the time it takes for the compiler to get >>> rebuilt gets reduced by 25%, from 27s to 20s (in a --disable-bootstrap >>> tree after touching a random source file). This is a pretty significant >>> reduction in compile time and disk io. >>> >>> Is this a good idea? >> >> Yes and no. Do we know if all ar support rcs now? > > It is easy to find out: run a configure check.
I see, I was not aware that non-GNU ar is supported. I posted a patch on gcc-patches that uses a configure check at https://gcc.gnu.org/ml/gcc-patches/2016-07/msg00991.html > > Andreas. > > -- > Andreas Schwab, sch...@linux-m68k.org > GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5 > "And now for something completely different."
