On Wed, Aug 07, 2019 at 11:33:40AM +0900, Masahiro Yamada wrote: > On Tue, Aug 6, 2019 at 7:56 PM Vasily Gorbik <gor@xxxxxxxxxxxxx> wrote: > > > > Currently empty .bss checks performed do not pay attention to "common > > objects" in object files which end up in .bss section eventually. > > > > The "size" tool is a part of binutils and since version 2.18 provides > > "--common" command line option, which allows to account "common objects" > > sizes in .bss section size. Utilize "size --common" to perform accurate > > check that .bss section is unused. Besides that the size tool handles > > object files without .bss section gracefully and doesn't require > > additional objdump run. > > > > The linux kernel requires binutils 2.20 since 4.13. > > > > Kbuild exports OBJSIZE to reference the right size tool. > > > > Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx> > > --- > > arch/s390/scripts/Makefile.chkbss | 3 +-- > > 1 file changed, 1 insertion(+), 2 deletions(-) > > > > diff --git a/arch/s390/scripts/Makefile.chkbss b/arch/s390/scripts/Makefile.chkbss > > index 884a9caff5fb..ba1d7a8a242f 100644 > > --- a/arch/s390/scripts/Makefile.chkbss > > +++ b/arch/s390/scripts/Makefile.chkbss > > @@ -11,8 +11,7 @@ chkbss: $(addprefix $(obj)/, $(chkbss-files)) > > > > quiet_cmd_chkbss = CHKBSS $< > > cmd_chkbss = \ > > - if $(OBJDUMP) -h $< | grep -q "\.bss" && \ > > - ! $(OBJDUMP) -j .bss -w -h $< | awk 'END { if ($$3) exit 1 }'; then \ > > + if ! $(OBJSIZE) --common $< | awk 'END { if ($$3) exit 1 }'; then \ > > While you are touching this line, > you may also want to replace 'awk' with $(AWK), > which is defined in the top-level Makefile. Indeed, thank you!