On Fri, Aug 28, 2020 at 09:56:28AM +0200, Thomas Huth wrote: > On 28/08/2020 09.47, Roman Bolshakov wrote: > > On Fri, Aug 28, 2020 at 09:24:10AM +0200, Thomas Huth wrote: > >> On 28/08/2020 08.54, Roman Bolshakov wrote: > >>> On Fri, Aug 28, 2020 at 07:00:19AM +0200, Thomas Huth wrote: > >>>> On 10/08/2020 15.06, Roman Bolshakov wrote: > >>>>> For compatibility with other SVR4 assemblers, '/' starts a comment on > >>>>> *-elf binutils target and thus division operator is not allowed [1][2]. > >>>>> That breaks cstart64.S build: > >>>>> > >>>>> x86/cstart64.S: Assembler messages: > >>>>> x86/cstart64.S:294: Error: unbalanced parenthesis in operand 1. > >>>>> > >>>>> The option is ignored on the Linux target of GNU binutils. > >>>>> > >>>>> 1. https://sourceware.org/binutils/docs/as/i386_002dChars.html > >>>>> 2. https://sourceware.org/binutils/docs/as/i386_002dOptions.html#index-_002d_002ddivide-option_002c-i386 > >>>>> > >>>>> Cc: Cameron Esfahani <dirty@xxxxxxxxx> > >>>>> Signed-off-by: Roman Bolshakov <r.bolshakov@xxxxxxxxx> > >>>>> --- > >>>>> x86/Makefile | 2 ++ > >>>>> 1 file changed, 2 insertions(+) > >>>>> > >>>>> diff --git a/x86/Makefile b/x86/Makefile > >>>>> index 8a007ab..22afbb9 100644 > >>>>> --- a/x86/Makefile > >>>>> +++ b/x86/Makefile > >>>>> @@ -1 +1,3 @@ > >>>>> include $(SRCDIR)/$(TEST_DIR)/Makefile.$(ARCH) > >>>>> + > >>>>> +COMMON_CFLAGS += -Wa,--divide > >>>> > >>>> Some weeks ago, I also played with an elf cross compiler and came to the > >>>> same conclusion, that we need this option there. Unfortunately, it does > >>>> not work with clang: > >>>> > >>>> https://gitlab.com/huth/kvm-unit-tests/-/jobs/707986800#L1629 > >>>> > >>>> You could try to wrap it with "cc-option" instead ... or use a proper > >>>> check in the configure script to detect whether it's needed or not. > >>>> > >>> > >>> Hi Thomas, > >>> > >>> Thanks for reviewing the series. I'll look into both options and will > >>> test with both gcc and clang afterwards. I can also update .travis.yml > >>> in a new patch to test the build on macOS. > >> > >> That would be great, thanks! Note that you need at least Clang v10 (the > >> one from Fedora 32 is fine) to compile the kvm-unit-tests. > >> > >> And if it's of any help, this was the stuff that I used in .travis.yml > >> for my experiments (might still be incomplete, though): > >> > >> - os: osx > >> osx_image: xcode12 > >> addons: > >> homebrew: > >> packages: > >> - bash > >> - coreutils > >> - qemu > >> - x86_64-elf-gcc > >> env: > >> - CONFIG="--cross-prefix=x86_64-elf-" > >> - BUILD_DIR="build" > >> - TESTS="umip" > >> - ACCEL="tcg" > >> > >> - os: osx > >> osx_image: xcode12 > >> addons: > >> homebrew: > >> packages: > >> - bash > >> - coreutils > >> - qemu > >> - i386-elf-gcc > > > > It's going to be i686-elf-gcc. > > Ah, there are two flavours? Ok, good to know. > i386-elf-gcc package was configured as x86_64-pc-elf target and then was renamed to x86_64-elf-gcc to match GCC target name (last December or in January). x86_64_elf-gcc can't properly link 32-bit ELF binaries because of GCC PR16470 (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=16470), PR32044 (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=32044). A cross-compiler is needed for that, that's why i686-elf-gcc was added in June/May: https://github.com/Homebrew/homebrew-core/pull/54946/commits/94ee559e6c6284539f74662a85ec20c174436677 But as far as I understand i686-pc-elf target is the same as i386-pc-elf in GCC/binutils (according to code inspection and a following discussion freenode's #gcc channel). FWIW, i686-elf-gcc can be installed in parallel with x86_64-elf-gcc. Thanks, Roman
