Has anyone faced this and how did you resolve this?
I have tried CodeSourcery as well as the NDK toolchain.

Some warnings are fixed in later kernels and some are just whining from the compiler/linker. It’s up to you to make the judgement on how to handle the warnings.

However, if you have something more specific we could of course take a look at it.

As a work-around you can build without the -Werror flag.

-Oskar

root@singdxs:/loveless/7.0.A.3.223/kernel# ARCH=arm CROSS_COMPILE=/opt/CodeSourcery/bin/arm-none-linux-gnueabi- make blue_hayabusa_defconfig
HOSTCC scripts/basic/fixdep
HOSTCC scripts/kconfig/conf.o
HOSTCC scripts/kconfig/zconf.tab.o
HOSTLD scripts/kconfig/conf
#
# configuration written to .config
#
root@singdxs:/loveless/7.0.A.3.223/kernel# ARCH=arm CROSS_COMPILE=/opt/CodeSourcery/bin/arm-none-linux-gnueabi- make
scripts/kconfig/conf –silentoldconfig Kconfig
CHK include/linux/version.h
CHK include/generated/utsrelease.h
make[1]: `include/generated/mach-types.h’ is up to date.
CC kernel/bounds.s
GEN include/generated/bounds.h
CC arch/arm/kernel/asm-offsets.s
GEN include/generated/asm-offsets.h
CALL scripts/checksyscalls.sh
HOSTCC scripts/genksyms/genksyms.o
HOSTCC scripts/genksyms/lex.o
HOSTCC scripts/genksyms/parse.o
HOSTLD scripts/genksyms/genksyms
CC scripts/mod/empty.o
HOSTCC scripts/mod/mk_elfconfig
MKELF scripts/mod/elfconfig.h
HOSTCC scripts/mod/file2alias.o
HOSTCC scripts/mod/modpost.o
HOSTCC scripts/mod/sumversion.o
HOSTLD scripts/mod/modpost
HOSTCC scripts/kallsyms
HOSTCC scripts/conmakehash
HOSTCC scripts/bin2c
CC init/main.o
CHK include/generated/compile.h
CC init/version.o
CC init/do_mounts.o
CC init/do_mounts_rd.o
CC init/do_mounts_initrd.o
LD init/mounts.o
CC init/initramfs.o
CC init/calibrate.o
LD init/built-in.o
HOSTCC usr/gen_init_cpio
GEN usr/initramfs_data.cpio
AS usr/initramfs_data.o
LD usr/built-in.o
CC arch/arm/vfp/vfpmodule.o
AS arch/arm/vfp/entry.o
AS arch/arm/vfp/vfphw.o
CC arch/arm/vfp/vfpsingle.o
CC arch/arm/vfp/vfpdouble.o
LD arch/arm/vfp/vfp.o
LD arch/arm/vfp/built-in.o
CC arch/arm/kernel/elf.o
AS arch/arm/kernel/entry-armv.o
AS arch/arm/kernel/entry-common.o
CC arch/arm/kernel/irq.o
CC arch/arm/kernel/process.o
CC arch/arm/kernel/ptrace.o
CC arch/arm/kernel/return_address.o
arch/arm/kernel/return_address.c:62:2: warning: #warning “TODO: return_address should use unwind tables” [-Wcpp]
CC arch/arm/kernel/setup.o
CC arch/arm/kernel/signal.o
CC arch/arm/kernel/sys_arm.o
CC arch/arm/kernel/stacktrace.o
CC arch/arm/kernel/time.o
CC arch/arm/kernel/traps.o
CC arch/arm/kernel/armksyms.o
CC arch/arm/kernel/module.o
AS arch/arm/kernel/sleep.o
CC arch/arm/kernel/sched_clock.o
CC arch/arm/kernel/smp.o
CC arch/arm/kernel/smp_tlb.o
CC arch/arm/kernel/smp_scu.o
CC arch/arm/kernel/crash_notes.o
CC arch/arm/kernel/kprobes.o
CC arch/arm/kernel/kprobes-decode.o
CC arch/arm/kernel/sys_oabi-compat.o
CC arch/arm/kernel/unwind.o
CC arch/arm/kernel/swp_emulate.o
CC arch/arm/kernel/pmu.o
CC arch/arm/kernel/perf_event.o
CC arch/arm/kernel/io.o
LD arch/arm/kernel/built-in.o
AS arch/arm/kernel/head.o
CC arch/arm/kernel/init_task.o
LDS arch/arm/kernel/vmlinux.lds
CC arch/arm/mm/dma-mapping.o
CC arch/arm/mm/extable.o
CC arch/arm/mm/fault.o
CC arch/arm/mm/init.o
CC arch/arm/mm/iomap.o
CC arch/arm/mm/fault-armv.o
CC arch/arm/mm/flush.o
CC arch/arm/mm/idmap.o
CC arch/arm/mm/ioremap.o
CC arch/arm/mm/mmap.o
CC arch/arm/mm/pgd.o
CC arch/arm/mm/mmu.o
CC arch/arm/mm/vmregion.o
CC arch/arm/mm/proc-syms.o
CC arch/arm/mm/alignment.o
arch/arm/mm/alignment.c:295:1: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
error, forbidden warning: alignment.c:295
make[1]: *** [arch/arm/mm/alignment.o] Error 1
make: *** [arch/arm/mm] Error 2

I tried to compile latest kernel (4.0.2.A.0.84) using arm-linux-gnueabi-gcc
The process stops because warnings and the -Werror flag set to compile the kernel.

If I actually remove the flag, compilation ends up successfully, but I don’t know whether it
will be OK to flash the new kernel to Neo V.

Do you have any suggestions about those warnings? Should I bother with them or not?

Thank you in advance

Xperia tipo dual => proj_TAP_defconfig
Xperia tipo => proj_TAP_defconfig
Xperia miro => proj_MES_defconfig
Xperia go => riogrande_lotus_defconfig

-Oskar