Hi Roger, > On 10 Feb 2026, at 12:41, Roger Pau Monné <[email protected]> wrote: > > On Tue, Feb 10, 2026 at 11:46:44AM +0100, Jan Beulich wrote: >> On 09.02.2026 11:46, Bertrand Marquis wrote: >>> --- /dev/null >>> +++ b/config/Darwin.mk >>> @@ -0,0 +1,6 @@ >>> +# Use GNU tool definitions as the tools we are using are either GNU >>> compatible >>> +# or we only use features which are supported on Mac OS. >>> +include $(XEN_ROOT)/config/StdGNU.mk >>> + >>> +# Cross compile on Mac OS, only hypervisor build has been tested, no tools >>> +XEN_COMPILE_ARCH = unknow >> >> While editing in the ABI aspect, it occurred to me to check what Apple has >> to say regarding their ABI. For both aarch64 and x86-64 they say they use >> the standard ABI with some modifications. We may want to evaluate whether >> those modifications are actually compatible with what we need. >> >> Talking of x86-64: Has building on an x86 Mac been tested as well? >> Especially if that doesn't work, it may want mentioning. > > I no longer have access to an x86 Mac, those are about to disappear. > > FWIW, I build x86 on Mac using the Docker containers, just as the CI > does. OSX Docker allows running x86 containers on arm64 using the > "Rosetta 2" binary translation layer. > > I've attempted doing a cross-build from an arm64 Mac using the x86-elf > toolchain, but got the following error: > > % make XEN_TARGET_ARCH=x86_64 CROSS_COMPILE=x86_64-elf- HOSTCC=gcc -C xen V=1 > [...] > /Library/Developer/CommandLineTools/usr/bin/make -f ./Rules.mk obj=common > need-builtin=1 > x86_64-elf-gcc -MMD -MP -MF common/.bitmap.o.d -m64 -DBUILD_ID > -fno-strict-aliasing -std=gnu99 -Wall -Wstrict-prototypes > -Wno-unused-but-set-variable -Wno-unused-local-typedefs -O1 > -fno-omit-frame-pointer -nostdinc -fno-builtin -fno-common > -fzero-init-padding-bits=all -Werror -Wredundant-decls -Wwrite-strings > -Wno-pointer-arith -Wdeclaration-after-statement -Wuninitialized -Wvla > -Wflex-array-member-not-at-end -Winit-self -pipe -D__XEN__ -include > ./include/xen/config.h -Wa,--strip-local-absolute -ffunction-sections > -fdata-sections -g -malign-data=abi -mindirect-branch=thunk-extern > -mindirect-branch-register -fno-jump-tables -mfunction-return=thunk-extern > -Wa,-mx86-used-note=no -fno-stack-protector -I./include -I./arch/x86/include > -I./arch/x86/include/generated -DXEN_IMG_OFFSET=0x200000 -msoft-float > -fno-pie -fno-exceptions -fno-asynchronous-unwind-tables -Wnested-externs > -DHAVE_AS_QUOTED_SYM -DHAVE_AS_MOVDIR -DHAVE_AS_ENQCMD > -DHAVE_AS_NOPS_DIRECTIVE -mno-red-zone -fpic -mno-mmx -mno-sse > -mskip-rax-setup -fcf-protection=branch -mmanual-endbr -fno-jump-tables > -mmemcpy-strategy=unrolled_loop:16:noalign,libcall:-1:noalign > -mmemset-strategy=unrolled_loop:16:noalign,libcall:-1:noalign -Wa,-I./include > -Wa,-I./include '-D__OBJECT_LABEL__=common/bitmap.o' > -mpreferred-stack-boundary=3 -c common/bitmap.c -o common/.bitmap.o.tmp -MQ > common/bitmap.o > ./arch/x86/include/asm/bitops.h: Assembler messages: > ./arch/x86/include/asm/bitops.h:511: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/bitops.h:511: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/bitops.h:511: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/bitops.h:511: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:20: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:20: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:21: Error: alternative feature outside of > featureset range > ./arch/x86/include/asm/nospec.h:20: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:20: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:21: Error: alternative feature outside of > featureset range > ./arch/x86/include/asm/nospec.h:28: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:28: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:29: Error: alternative feature outside of > featureset range > ./arch/x86/include/asm/nospec.h:28: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:28: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:29: Error: alternative feature outside of > featureset range > ./arch/x86/include/asm/nospec.h:28: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:28: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:29: Error: alternative feature outside of > featureset range > ./arch/x86/include/asm/nospec.h:20: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:20: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:21: Error: alternative feature outside of > featureset range > ./arch/x86/include/asm/nospec.h:20: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:20: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:21: Error: alternative feature outside of > featureset range > ./arch/x86/include/asm/nospec.h:28: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:28: Error: found ' > ', expected: ')' > ./arch/x86/include/asm/nospec.h:29: Error: alternative feature outside of > featureset range > > I haven't investigated further. Seems like some issue with > alternative and the uses of CPUID defines. We probably want to > mention in the commit message that only arm64 builds have been tested > so far.
I just tried the same and could reproduce that. This is apparently not related to mac os but to binutils (2.45.1 on my side) After some digging i found out that this can be triggered with a simple assembler test where .if (2/32) triggers the same error, while .if 2/32 is fine (ie parenthesis are the source of the issue). So the same error would probably occur with the same binutils version in linux i guess (unless it brew specific version or patches which are creating that). I did not dig further than that but we should keep that in mind in case this comes back in other scenarios. Cheers Bertrand > > Thanks, Roger.
