# git rev-parse -q --verify 8dcd71b45df34d9b903450fab147ee8c1e6c16b5^{commit}
# git fetch -q -n -f git://gitlab.ozlabs.ibm.com/linuxppc/linux.git next-test
# git rev-parse -q --verify 8dcd71b45df34d9b903450fab147ee8c1e6c16b5^{commit}
8dcd71b45df34d9b903450fab147ee8c1e6c16b5
# git checkout -q -f -B kisskb 8dcd71b45df34d9b903450fab147ee8c1e6c16b5
# git clean -qxdf
# < git log -1
# commit 8dcd71b45df34d9b903450fab147ee8c1e6c16b5
# Author: Nathan Chancellor <natechancellor@gmail.com>
# Date:   Mon Nov 18 21:57:12 2019 -0700
# 
#     powerpc/prom_init: Use -ffreestanding to avoid a reference to bcmp
#     
#     LLVM revision r374662 gives LLVM the ability to convert certain loops
#     into a reference to bcmp as an optimization; this breaks
#     prom_init_check.sh:
#     
#         CALL    arch/powerpc/kernel/prom_init_check.sh
#       Error: External symbol 'bcmp' referenced from prom_init.c
#       make[2]: *** [arch/powerpc/kernel/Makefile:196: prom_init_check] Error 1
#     
#     bcmp is defined in lib/string.c as a wrapper for memcmp so this could
#     be added to the whitelist. However, commit
#     450e7dd4001f ("powerpc/prom_init: don't use string functions from
#     lib/") copied memcmp as prom_memcmp to avoid KASAN instrumentation so
#     having bcmp be resolved to regular memcmp would break that assumption.
#     Furthermore, because the compiler is the one that inserted bcmp, we
#     cannot provide something like prom_bcmp.
#     
#     To prevent LLVM from being clever with optimizations like this, use
#     -ffreestanding to tell LLVM we are not hosted so it is not free to
#     make transformations like this.
#     
#     Reviewed-by: Nick Desaulneris <ndesaulniers@google.com>
#     Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
#     Link: https://lore.kernel.org/r/20191119045712.39633-4-natechancellor@gmail.com
# < /opt/cross/kisskb/gcc-4.6.3-nolibc/sh4-linux/bin/sh4-linux-gcc --version
# < /opt/cross/kisskb/gcc-4.6.3-nolibc/sh4-linux/bin/sh4-linux-ld --version
# < git log --format=%s --max-count=1 8dcd71b45df34d9b903450fab147ee8c1e6c16b5
# < make -s -j 24 ARCH=sh O=/kisskb/build/powerpc-next_sh-defconfig_sh4 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/sh4-linux/bin/sh4-linux-  defconfig
# make -s -j 24 ARCH=sh O=/kisskb/build/powerpc-next_sh-defconfig_sh4 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/sh4-linux/bin/sh4-linux-  
  Generating include/generated/machtypes.h
<stdin>:1511:2: warning: #warning syscall clone3 not implemented [-Wcpp]
/kisskb/src/arch/sh/kernel/cpu/sh4/../sh3/../../entry-common.S: Assembler messages:
/kisskb/src/arch/sh/kernel/cpu/sh4/../sh3/../../entry-common.S:385: Warning: overflow in branch to syscall_exit_work; converted into longer instruction sequence
/kisskb/src/arch/sh/kernel/cpu/sh4/../sh3/../../entry-common.S:388: Warning: overflow in branch to syscall_exit_work; converted into longer instruction sequence
/kisskb/src/mm/vmstat.c: In function 'sysctl_vm_numa_stat_handler':
/kisskb/src/mm/vmstat.c:90:5: warning: 'oldval' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl':
/kisskb/src/kernel/printk/printk.c:204:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/kernel/rcu/srcutree.c: In function 'init_srcu_struct_fields':
/kisskb/src/kernel/rcu/srcutree.c:140:32: warning: 'levelspread[<Udaa0>]' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/kernel/rcu/srcutree.c:88:6: note: 'levelspread[<Udaa0>]' was declared here
/kisskb/src/drivers/base/regmap/regmap.c: In function 'regmap_raw_read':
/kisskb/src/drivers/base/regmap/regmap.c:2591:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/drivers/base/regmap/regmap.c: In function '_regmap_raw_write':
/kisskb/src/drivers/base/regmap/regmap.c:1852:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/mm/hugetlb.c: In function 'alloc_pool_huge_page':
/kisskb/src/mm/hugetlb.c:1497:5: warning: 'page' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/fs/proc/inode.c: In function 'proc_reg_open':
/kisskb/src/include/linux/list.h:65:12: warning: 'pdeo' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/fs/proc/inode.c:338:21: note: 'pdeo' was declared here
/kisskb/src/drivers/sh/clk/cpg.c: In function 'r8':
/kisskb/src/drivers/sh/clk/cpg.c:41:2: warning: passing argument 1 of 'ioread8' discards 'const' qualifier from pointer target type [enabled by default]
/kisskb/src/include/asm-generic/iomap.h:29:21: note: expected 'void *' but argument is of type 'const void *'
/kisskb/src/drivers/sh/clk/cpg.c: In function 'r16':
/kisskb/src/drivers/sh/clk/cpg.c:46:2: warning: passing argument 1 of 'ioread16' discards 'const' qualifier from pointer target type [enabled by default]
/kisskb/src/include/asm-generic/iomap.h:30:21: note: expected 'void *' but argument is of type 'const void *'
/kisskb/src/drivers/sh/clk/cpg.c: In function 'r32':
/kisskb/src/drivers/sh/clk/cpg.c:51:2: warning: passing argument 1 of 'ioread32' discards 'const' qualifier from pointer target type [enabled by default]
/kisskb/src/include/asm-generic/iomap.h:32:21: note: expected 'void *' but argument is of type 'const void *'
/kisskb/src/fs/ext4/readpage.c: In function 'ext4_mpage_readpages':
/kisskb/src/fs/ext4/readpage.c:410:1: warning: the frame size of 1180 bytes is larger than 1024 bytes [-Wframe-larger-than=]
/kisskb/src/fs/mpage.c: In function '__mpage_writepage':
/kisskb/src/fs/mpage.c:690:1: warning: the frame size of 1148 bytes is larger than 1024 bytes [-Wframe-larger-than=]
/kisskb/src/fs/mpage.c: In function 'do_mpage_readpage':
/kisskb/src/fs/mpage.c:338:1: warning: the frame size of 1108 bytes is larger than 1024 bytes [-Wframe-larger-than=]
/kisskb/src/drivers/usb/core/devio.c: In function 'async_completed':
/kisskb/src/drivers/usb/core/devio.c:625:23: warning: 'errno' may be used uninitialized in this function [-Wuninitialized]
  Kernel: arch/sh/boot/zImage is ready
Completed OK
# rm -rf /kisskb/build/powerpc-next_sh-defconfig_sh4
# Build took: 0:01:37.100405