Fix compilation with gcc 5.1 (avoid internal compiler error), by
replacing explicit -march +nofp+nosimd options with -mgeneral-regs-only.
This also enables the removal of some further conditional build flag
setting.
libgcc for boot environment isn't always present and compatible.
libgcc is often absent if endianness or bit-size at boot is different
from running OS.
libgcc may use optimised opcodes that aren't available on boot time.
So instead of relying on libgcc shipped with the compiler, supply
the functions in GRUB directly.
Tests are present to ensure that those replacement functions behave the
way compiler expects them to.
Add -msoft-float alongside clang arguments to specify ABI.
Specify ABI in asm files explicitly.
This trigers asm warning due to gcc failing to propagate -msoft-float
but it's tolerable.
aarch64 toolchains do not support the -msoft-float option added by
commit 3661261f. Insted, for arm64 use -march=armv8-a+nofp+nosimd.
Reported-by: Ryan Harkin <ryan.harkin@linaro.org>
This makes it possible to build generally-useful utilities such as
grub-mount even if the rest of GRUB has not been ported to the target
CPU.
* configure.ac: Add "none" platform. Default to it for unsupported
CPUs rather than stopping with a fatal error. Don't downgrade
x86_64-none to i386. Define COND_real_platform Automake conditional
if the platform is anything other than "none". Don't do any include
directory linking for "none".
* Makefile.am: Skip building grub-core and all bootcheck targets if
!COND_real_platform.
* include/grub/time.h: Don't include <grub/cpu/time.h> if GRUB_UTIL
is defined.
* configure.ac: Remove -m64 from checks for -mcmodel=large and
-mno-red-zone. These are always either unnecessary (x86_64-emu) or
already in TARGET_CFLAGS at this point, and they produce incorrect
results when building for x32.
* grub-core/kern/x86_64/dl.c (grub_arch_dl_relocate_symbols): Cast
pointers to Elf64_Xword via grub_addr_t, in order to work on x32.
* include/grub/x86_64/types.h (GRUB_TARGET_SIZEOF_VOID_P,
GRUB_TARGET_SIZEOF_LONG): Define to 4 on x32.
This allows providing separate LDFLAGS for build and host environments, which
are not necessary the same for cross-compile case. In particular, it allows
building host programs statically to not depend on presence of libraries at
run-time (e.g. MinGW DLLs on Windows) while continue to use default dynamic
linking at build time.
Also fix obsolete comments in confgure.ac - we do use different environment
for build and host now.
