Messages in this thread | | | From | Jan-Simon Möller <> | Subject | Re: [llvmlinux] [PATCH 3/4] x86: Allow building 16-bit code with -m16 with toolchains that support it | Date | Tue, 14 Jan 2014 20:14:53 +0100 |
| |
Hi David,
what version of clang did you use btw ?
--
Dipl.-Ing. Jan-Simon Möller
jansimon.moeller@gmx.de Am Mittwoch, 8. Januar 2014, 11:21:22 schrieb David Woodhouse: > I have this working with LLVM/Clang, and a PR is filed for GCC because > the current hacks we have to do to *try* to ensure that .code16gcc is > the first thing in the asm output are horrid. > > Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> > --- > arch/x86/Makefile | 15 +++++++++++---- > 1 file changed, 11 insertions(+), 4 deletions(-) > > diff --git a/arch/x86/Makefile b/arch/x86/Makefile > index ef19271..60fc67d 100644 > --- a/arch/x86/Makefile > +++ b/arch/x86/Makefile > @@ -13,14 +13,21 @@ endif > > # How to compile the 16-bit code. Note we always compile for -march=i386; > # that way we can complain to the user if the CPU is insufficient. > -REALMODE_CFLAGS := -m32 -g -Os -D__KERNEL__ -DDISABLE_BRANCH_PROFILING \ > +# > +# We really want GCC to have a -m16 option like clang, so that we don't > +# have to play these evil and unreliable tricks to ensure that our > +# asm(".code16gcc") is first in the asm output. http://gcc.gnu.org/PR59672 > +CODE16GCC_CFLAGS := -m32 -include $(srctree)/arch/x86/boot/code16gcc.h \ > + $(call cc-option, -fno-toplevel-reorder,\ > + $(call cc-option, -fno-unit-at-a-time)) > +M16_CFLAGS := -m16 > + > +REALMODE_CFLAGS := -g -Os -D__KERNEL__ -DDISABLE_BRANCH_PROFILING \ > + $(call cc-option, $(M16_CFLAGS), $(CODE16GCC_CFLAGS)) \ > -Wall -Wstrict-prototypes -march=i386 -mregparm=3 \ > - -include $(srctree)/arch/x86/boot/code16gcc.h \ > -fno-strict-aliasing -fomit-frame-pointer -fno-pic \ > -mno-mmx -mno-sse \ > $(call cc-option, -ffreestanding) \ > - $(call cc-option, -fno-toplevel-reorder,\ > - $(call cc-option, -fno-unit-at-a-time)) \ > $(call cc-option, -fno-stack-protector) \ > $(call cc-option, -mpreferred-stack-boundary=2) > export REALMODE_CFLAGS
-- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |