On Sat, Feb 2, 2019 at 12:12 AM Borislav Petkov <bp@xxxxxxxxx> wrote: > > On Fri, Feb 01, 2019 at 08:58:13PM +0900, Masahiro Yamada wrote: > > Variables assigned with ':=' are evaluated just on parsing Makefile. > > > > The scripts/Makefile.build is parsed over and over again, > > so the compiler is invoked hundreds times to test these four options > > even when you are not actually building any new objects. > > > > It is mitigated by replacing ':=' with '=', > > but they are still evaluated multiple times when generating asm-offset. > > Now that you mention it, how about ?= '?=' is the same as '=' here. > disable_extra_cc_dbg ?= $(call cc-option,-gno-as-locview-support) > disable_extra_cc_dbg += $(call cc-option,-fno-dwarf2-cfi-asm) > disable_extra_cc_dbg += $(call cc-option,-feliminate-unused-debug-symbols) > disable_extra_cc_dbg += $(call cc-option,-gno-statement-frontiers) > > With it, the slowdown of the incremental build is ~0.2s (on an old laptop): > > defconfig without: 9.6128 +- 0.0327 seconds time elapsed ( +- 0.34% ) > > vs > > defconfig with: 9.8483 +- 0.0273 seconds time elapsed ( +- 0.28% ) > > > -- > Regards/Gruss, > Boris. > > Good mailing practices for 400: avoid top-posting and trim the reply. -- Best Regards Masahiro Yamada
