bug#41982: [PATCH 0/1] gnu: grub: Cross-build fix for system i686-linux.

[Ludovic Courtès]

Hi,

Jan Nieuwenhuizen <janneke@gnu.org> skribis:

> Attempting to reconfigure a i686-linux guix system to a Hurd system, I
> found that the Grub(-minimal) cross build fails like this
>
> 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)'

Interesting.  Why doesn’t it happen when doing:

  guix build grub-minimal -s i686-linux

?  That’s because ‘as’ supports ‘.code64’ there?

> I am not sure if and how to report this upstream.  Ideas for a bug
> description?  Apparently, non-cross builds "just" work (how?!).

The issue seems to be that ‘.code64’ is not supported by cross
assemblers to 32-bit Intel, right?

Is this a defect of cross-as in general, or a misconfiguration in our
Guix package?  Or is this normal behavior that should be fixed in GRUB?

Anyway, the patch LGTM!

Thanks,
Ludo’.