On Sat, Dec 17, 2022 at 4:07 PM Rong Tao <rtoax@xxxxxxxxxxx> wrote: > > From: Rong Tao <rongtao@xxxxxxxx> > > In the absence of a CONFIG_FUNCTION_ALIGNMENT defined, Does it happen in the mainline kernel? CONFIG_FUNCTION_ALIGNMENT is always defined as far as I understood arch/Kconfig. > -falign-functions= > will be given a null value, which results in a compilation error, as > follows: > > $ make -C samples/bpf/ > ... > CC /home/sdb/Git/linux/samples/bpf/syscall_nrs.s > gcc: error: missing argument to ‘-falign-functions=’ > make[2]: *** [scripts/Makefile.build:118: /home/sdb/Git/linux/samples > /bpf/syscall_nrs.s] Error 1 > make[1]: *** [Makefile:1996: /home/sdb/Git/linux/samples/bpf] Error 2 > make[1]: Leaving directory '/home/sdb/Git/linux' > make: *** [Makefile:269: all] Error 2 > > Signed-off-by: Rong Tao <rongtao@xxxxxxxx> > --- > Makefile | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/Makefile b/Makefile > index 6aa709df6bde..57cce4c8f8a2 100644 > --- a/Makefile > +++ b/Makefile > @@ -1006,9 +1006,11 @@ KBUILD_CFLAGS += $(CC_FLAGS_CFI) > export CC_FLAGS_CFI > endif > > +ifdef CONFIG_FUNCTION_ALIGNMENT > ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0) > KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT) > endif > +endif > > # arch Makefile may override CC so keep this after arch Makefile is included > NOSTDINC_FLAGS += -nostdinc > -- > 2.38.1 > -- Best Regards Masahiro Yamada
