Hi! When cross-compiling Grub-2.04 from i386-linux-gnu to i586-pc-hurd on GNU Guix, I got this error --8<---------------cut here---------------start------------->8--- i586-pc-gnu-gcc -DHAVE_CONFIG_H -I. -I.. -Wall -W -DGRUB_MACHINE_PCBIOS=1 -DGRUB_MACHINE=I386_PC -m32 -nostdinc -isystem /gnu/store/5s0ldm31100d9ix15d1lmbsvi0aa77pq-gcc-cross-i586-pc-gnu-7.5.0-lib/lib/gcc/i586-pc-gnu/7.5.0/include -I../include -I../include -DGRUB_FILE=\"lib/cmos_datetime.c\" -I. -I. -I.. -I.. -I../include -I../include -I../grub-core/lib/libgcrypt-grub/src/ -D_FILE_OFFSET_BITS=64 -Os -Wall -W -Wshadow -Wpointer-arith -Wundef -Wchar-subscripts -Wcomment -Wdeprecated-declarations -Wdisabled-optimization -Wdiv-by-zero -Wfloat-equal -Wformat-extra-args -Wformat-security -Wformat-y2k -Wimplicit -Wimplicit-function-declaration -Wimplicit-int -Wmain -Wmissing-braces -Wmissing-format-attribute -Wmultichar -Wparentheses -Wreturn-type -Wsequence-point -Wshadow -Wsign-compare -Wswitch -Wtrigraphs -Wunknown-pragmas -Wunused -Wunused-function -Wunused-label -Wunused-parameter -Wunused-value -Wunused-variable -Wwrite-strings -Wnested-externs -Wstrict-prototypes -g -Wredundant-decls -Wmissing-prototypes -Wmissing-declarations -Wextra -Wattributes -Wendif-labels -Winit-self -Wint-to-pointer-cast -Winvalid-pch -Wmissing-field-initializers -Wnonnull -Woverflow -Wvla -Wpointer-to-int-cast -Wstrict-aliasing -Wvariadic-macros -Wvolatile-register-var -Wpointer-sign -Wmissing-include-dirs -Wmissing-prototypes -Wmissing-declarations -Wformat=2 -march=i386 -m32 -mrtd -mregparm=3 -falign-jumps=1 -falign-loops=1 -falign-functions=1 -freg-struct-return -mno-mmx -mno-sse -mno-sse2 -mno-sse3 -mno-3dnow -msoft-float -fno-dwarf2-cfi-asm -mno-stack-arg-probe -fno-asynchronous-unwind-tables -fno-unwind-tables -fno-stack-protector -Wtrampolines -Werror -ffreestanding -MT lib/datetime_module-cmos_datetime.o -MD -MP -MF lib/.deps-core/datetime_module-cmos_datetime.Tpo -c -o lib/datetime_module-cmos_datetime.o `test -f 'lib/cmos_datetime.c' || echo './'`lib/cmos_datetime.c lib/i386/relocator64.S: Assembler messages: lib/i386/relocator64.S:66: Error: unknown pseudo-op: `.code64' lib/i386/relocator64.S:74: Error: bad register name `%rax' lib/i386/relocator64.S:98: Error: bad register name `%rax' lib/i386/relocator64.S:132: Error: bad register name `%rip)' make[3]: *** [Makefile:32165: lib/i386/relocator_module-relocator64.o] Error 1 make[3]: *** Waiting for unfinished jobs.... mv -f lib/i386/.deps-core/relocator_module-relocator_common_c.Tpo lib/i386/.deps-core/relocator_module-relocator_common_c.Po mv -f lib/i386/.deps-core/relocator_module-relocator.Tpo lib/i386/.deps-core/relocator_module-relocator.Po mv -f kern/.deps-core/elf_module-elf.Tpo kern/.deps-core/elf_module-elf.Po mv -f lib/.deps-core/datetime_module-cmos_datetime.Tpo lib/.deps-core/datetime_module-cmos_datetime.Po mv -f fs/.deps-core/xfs_module-xfs.Tpo fs/.deps-core/xfs_module-xfs.Po mv -f lib/.deps-core/crypto_module-crypto.Tpo lib/.deps-core/crypto_module-crypto.Po mv -f lib/.deps-core/relocator_module-relocator.Tpo lib/.deps-core/relocator_module-relocator.Po make[3]: Leaving directory '/tmp/guix-build-grub-minimal-2.04.drv-0/grub-2.04/grub-core' make[2]: *** [Makefile:26403: all] Error 2 make[2]: Leaving directory '/tmp/guix-build-grub-minimal-2.04.drv-0/grub-2.04/grub-core' make[1]: *** [Makefile:11304: all-recursive] Error 1 make[1]: Leaving directory '/tmp/guix-build-grub-minimal-2.04.drv-0/grub-2.04' make: *** [Makefile:3343: all] Error 2 command "make" "-j" "8" failed with status 2 --8<---------------cut here---------------end--------------->8--- In Guix we are now using the patch attached, which seems to fix this for us. We are not entirely sure if this is the proper fix though, see . Paraphrasing the questions raised there: why does this seem to compile on i386? Is that because the non-cross 32-bit ‘as’ supports ‘.code64’? Is the Guix's cross-assembler ‘i586-pc-gnu-as’ configured wrong and should it support this? (FWIW, this is not specific for the Hurd, cross compiling from i686-linux-gnu to i686-linux-gnu show the same error. The use case for that may be a bit thin to warrant a bug report.) Ideas welcome! Greetings, Janneke