# git gc
# git rev-parse -q --verify b1fbfcb4a20949df08dd995927cdc5ad220c128d^{commit}
# git fetch -q -n -f git://gitlab.ozlabs.ibm.com/mirror/linux-kbuild.git for-next
# git rev-parse -q --verify b1fbfcb4a20949df08dd995927cdc5ad220c128d^{commit}
b1fbfcb4a20949df08dd995927cdc5ad220c128d
# git checkout -q -f -B kisskb b1fbfcb4a20949df08dd995927cdc5ad220c128d
# git clean -qxdf
# < git log -1
# commit b1fbfcb4a20949df08dd995927cdc5ad220c128d
# Author: Masahiro Yamada <yamada.masahiro@socionext.com>
# Date:   Mon Nov 18 13:52:47 2019 +0900
# 
#     kbuild: make single target builds even faster
#     
#     Commit 2dffd23f81a3 ("kbuild: make single target builds much faster")
#     made the situation much better.
#     
#     To improve it even more, apply the similar idea to the top Makefile.
#     Trim unrelated directories from build-dirs.
#     
#     The single build code must be moved above the 'descend' target.
#     
#     Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
#     Tested-by: Jens Axboe <axboe@kernel.dk>
# < /opt/cross/kisskb/gcc-4.6.3-nolibc/arm-unknown-linux-gnueabi/bin/arm-unknown-linux-gnueabi-gcc --version
# < /opt/cross/kisskb/gcc-4.6.3-nolibc/arm-unknown-linux-gnueabi/bin/arm-unknown-linux-gnueabi-ld --version
# < git log --format=%s --max-count=1 b1fbfcb4a20949df08dd995927cdc5ad220c128d
# < make -s -j 24 ARCH=arm O=/kisskb/build/kbuild_versatile_defconfig_arm CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/arm-unknown-linux-gnueabi/bin/arm-unknown-linux-gnueabi-  versatile_defconfig
# make -s -j 24 ARCH=arm O=/kisskb/build/kbuild_versatile_defconfig_arm CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/arm-unknown-linux-gnueabi/bin/arm-unknown-linux-gnueabi-  
/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/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/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
WARNING: "return_address" [vmlinux] is a static EXPORT_SYMBOL_GPL
Completed OK
# rm -rf /kisskb/build/kbuild_versatile_defconfig_arm
# Build took: 0:09:33.585382