On Fri, May 10, 2019 at 1:47 AM Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote: > > From: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> > > On Thu, May 9, 2019 at 4:11 PM Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote: > > > BTW, is this a speedup when doing CC/LD FLAGS etc checks unconditionally? > > > > Yes. > > cc-option is somewhat costly because it invoked the compiler to > > check if the given flag is supported. > > > > So, I want to get rid of as many cc-option calls as possible. > > > > > > > Asking in general - do you have any numbers :-)? > > > > Removing a couple of cc-options does not make > > a measurable difference in general use-cases. > > > > But, this might be more beneficial for chrome OS > > because $(CC) is a wrapper and invoking it is much more expensive. > > Android does too, which we plan on removing as we recently measured > the performance cost of 5% for having a Python wrapper to aid in > bisection. > > Anyways, I checked these options with clang 4 and gcc 4.6.4 in godbolt. > Tested-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > -- > Thanks, > ~Nick Desaulniers Applied to linux-kbuild. -- Best Regards Masahiro Yamada
