# git rev-parse -q --verify 8dcd71b45df34d9b903450fab147ee8c1e6c16b5^{commit} 8dcd71b45df34d9b903450fab147ee8c1e6c16b5 already have revision, skipping fetch # git checkout -q -f -B kisskb 8dcd71b45df34d9b903450fab147ee8c1e6c16b5 # git clean -qxdf # < git log -1 # commit 8dcd71b45df34d9b903450fab147ee8c1e6c16b5 # Author: Nathan Chancellor # 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 # Signed-off-by: Nathan Chancellor # Signed-off-by: Michael Ellerman # Link: https://lore.kernel.org/r/20191119045712.39633-4-natechancellor@gmail.com # < /opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux-gcc --version # < /opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux-ld --version # < git log --format=%s --max-count=1 8dcd71b45df34d9b903450fab147ee8c1e6c16b5 # < make -s -j 32 ARCH=powerpc O=/kisskb/build/powerpc-next_83xx_mpc8313_rdb_defconfig_powerpc-gcc4.6 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- 83xx/mpc8313_rdb_defconfig # make -s -j 32 ARCH=powerpc O=/kisskb/build/powerpc-next_83xx_mpc8313_rdb_defconfig_powerpc-gcc4.6 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- /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 /kisskb/src/drivers/tty/serial/8250/8250_core.c: In function 'univ8250_release_irq': /kisskb/src/drivers/tty/serial/8250/8250_core.c:248:18: warning: 'i' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/tty/serial/8250/8250_core.c:228:19: note: 'i' was declared here /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] INFO: Uncompressed kernel (size 0x5db0a0) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0x600000) Image Name: Linux-5.4.0-rc2-g8dcd71b45df3 Created: Tue Nov 26 00:09:59 2019 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 2965067 Bytes = 2895.57 KiB = 2.83 MiB Load Address: 00000000 Entry Point: 00000000 Completed OK # rm -rf /kisskb/build/powerpc-next_83xx_mpc8313_rdb_defconfig_powerpc-gcc4.6 # Build took: 0:00:46.881503