On 09.08.2018 18:40, Alistair Strachan wrote: > When building with CONFIG_EFI and CONFIG_EFI_STUB on ARM, the libstub > Makefile would use -mno-single-pic-base without checking it was > supported by the compiler. As the ARM (32-bit) clang backend does not > support this flag, the build would fail. > > This changes the Makefile to check the compiler's support for > -mno-single-pic-base before using it, similar to c1c386681bd7 ("ARM: > 8767/1: add support for building ARM kernel with clang").
Looks good to me: Reviewed-by: Stefan Agner <ste...@agner.ch> > > Cc: Stefan Agner <ste...@agner.ch> > Cc: Ard Biesheuvel <ard.biesheu...@linaro.org> > Cc: Will Deacon <will.dea...@arm.com> > Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> > Cc: Russell King <li...@armlinux.org.uk> > Cc: linux-efi@vger.kernel.org > Cc: linux-arm-ker...@lists.infradead.org > Signed-off-by: Alistair Strachan <astrac...@google.com> > --- > drivers/firmware/efi/libstub/Makefile | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/firmware/efi/libstub/Makefile > b/drivers/firmware/efi/libstub/Makefile > index a34e9290a699..91339d13f2a1 100644 > --- a/drivers/firmware/efi/libstub/Makefile > +++ b/drivers/firmware/efi/libstub/Makefile > @@ -13,7 +13,8 @@ cflags-$(CONFIG_X86) += -m$(BITS) > -D__KERNEL__ -O2 \ > > cflags-$(CONFIG_ARM64) := $(subst -pg,,$(KBUILD_CFLAGS)) -fpie > cflags-$(CONFIG_ARM) := $(subst -pg,,$(KBUILD_CFLAGS)) \ > - -fno-builtin -fpic -mno-single-pic-base > + -fno-builtin -fpic \ > + $(call cc-option,-mno-single-pic-base) > > cflags-$(CONFIG_EFI_ARMSTUB) += -I$(srctree)/scripts/dtc/libfdt