On 15.10.2021 17:52, Anthony PERARD wrote: > On Thu, Oct 14, 2021 at 10:32:05AM +0200, Jan Beulich wrote: >> On 24.08.2021 12:50, Anthony PERARD wrote: >>> -$(obj)/cmdline.S: $(src)/cmdline.c $(CMDLINE_DEPS) $(src)/build32.lds >>> - $(MAKE) -f $(BASEDIR)/$(src)/build32.mk -C $(obj) $(@F) >>> CMDLINE_DEPS="$(CMDLINE_DEPS)" >>> +CFLAGS_x86_32 := -m32 -march=i686 >>> +CFLAGS_x86_32 += -fno-strict-aliasing >>> +CFLAGS_x86_32 += -std=gnu99 >>> +CFLAGS_x86_32 += -Wall -Wstrict-prototypes >>> +$(call cc-option-add,CFLAGS_x86_32,CC,-Wdeclaration-after-statement) >>> +$(call cc-option-add,CFLAGS_x86_32,CC,-Wno-unused-but-set-variable) >>> +$(call cc-option-add,CFLAGS_x86_32,CC,-Wno-unused-local-typedefs) >>> +$(call cc-options-add,CFLAGS_x86_32,CC,$(EMBEDDED_EXTRA_CFLAGS)) >>> +CFLAGS_x86_32 += -Werror -fno-builtin -g0 -msoft-float >>> +CFLAGS_x86_32 += -I$(srctree)/include >> >> I'm afraid I'm not convinced that having to keep this in sync with the >> original is in fair balance with the removal of build32.mk. > > Why would this needs to be kept in sync with the original? I would > actually like to get rid of Config.mk, I don't see the point in sharing > CFLAGS between a kernel and userspace binaries. Also, I hope one day > that we can have the hypervisor in its own repo, and thus they won't be > any Config.mk to keep in sync with.
My point wasn't about Config.mk as the reference in particular, but ... > The goal of this patch is less about removing build32.mk, and more about > using the rest of the build system infrastructure to build those few > 32bits objects, and been able to use the automatic dependencies > generation and other things without having to duplicate them. > > It probably make the build a bit faster as there is two less invocation > of $(MAKE) (which parse Config.mk). > > As for a possible change: instead of having those x86_32 flags in > arch/x86/boot/, I could have them in arch/x86/arch.mk. Linux does > something like that were it prepare REALMODE_CFLAGS. > > I know it's a bit annoying to have another list x86_32 cflags, but I > don't see how we can extract them from Config.mk (in a Makefile where we > want to use both x86_32 and x86_64 flags). ... about the general (apparent) plan to have two sets of flags, which may not strictly _need_ to remain in sync, but better would. So while I appreciate the alternative of putting stuff in arch.mk, I'd still like to see common things like -W... to get probed for and added to whichever variable just once. Jan
