Buildresult: gustavoars/alpha-defconfig/alpha-gcc4.9 built on Sep 30 2020, 13:34

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Status:	OK
Date/Time:	Sep 30 2020, 13:34
Duration:	0:01:16.021288
Builder:	ka2
Revision:	include: jhash/signal: Fix fall-through warnings for Clang (`736116436e5b99b46e1a49c17cae6f6ee0a30e84)`
Target:	gustavoars/alpha-defconfig/alpha-gcc4.9
Branch:	gustavoars
Compiler:	alpha-gcc4.9 (alpha-linux-gcc (GCC) 4.9.4 / GNU ld (GNU Binutils) 2.29.1.20170915)
Config:	defconfig (download)
Log:	Download original Possible warnings (2) <stdin>:1511:2: warning: #warning syscall clone3 not implemented [-Wcpp] WARNING: modpost: "saved_config" [vmlinux] is COMMON symbol Full Log # git rev-parse -q --verify 736116436e5b99b46e1a49c17cae6f6ee0a30e84^{commit} 736116436e5b99b46e1a49c17cae6f6ee0a30e84 already have revision, skipping fetch # git checkout -q -f -B kisskb 736116436e5b99b46e1a49c17cae6f6ee0a30e84 # git clean -qxdf # < git log -1 # commit 736116436e5b99b46e1a49c17cae6f6ee0a30e84 # Author: Gustavo A. R. Silva <gustavoars@kernel.org> # Date: Wed Sep 2 23:25:55 2020 -0500 # # include: jhash/signal: Fix fall-through warnings for Clang # # In preparation to enable -Wimplicit-fallthrough for Clang, explicitly # add break statements instead of letting the code fall through to the # next case. # # This patch adds four break statements that, together, fix almost 80,000 # warnings when building Linux 5.9-rc3 with Clang 12.0.0 and this[1] change # reverted. Notice that in order to enable -Wimplicit-fallthrough for Clang, # such change[1] is meant to be reverted at some point. So, this patch helps # to move in that direction. # # Something important to mention is that there is currently a discrepancy # between GCC and Clang when dealing with switch fall-through to empty case # statements or to cases that only contain a break/continue/return # statement[2][3][4]. # # Now that the -Wimplicit-fallthrough option has been globally enabled[5], # any compiler should really warn on missing either a fallthrough annotation # or any of the other case-terminating statements (break/continue/return/ # goto) when falling through to the next case statement. Making exceptions # to this introduces variation in case handling which may continue to lead # to bugs, misunderstandings, and a general lack of robustness. The point # of enabling options like -Wimplicit-fallthrough is to prevent human error # and aid developers in spotting bugs before their code is even built/ # submitted/committed, therefore eliminating classes of bugs. So, min order # to really accomplish this, we should, and can, move in the direction of # addressing any error-prone scenarios and get rid of the unintentional # fallthrough bug-class in the kernel, entirely, even if there is some minor # redundancy. Better to have explicit case-ending statements than continue to # have exceptions where one must guess as to the right result. The compiler # will eliminate any actual redundancy. # # [1] commit e2079e93f562c ("kbuild: Do not enable -Wimplicit-fallthrough for clang for now") # [2] https://github.com/ClangBuiltLinux/linux/issues/636 # [3] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91432 # [4] https://godbolt.org/z/xgkvIh # [5] commit a035d552a93b ("Makefile: Globally enable fall-through warning") # # Co-developed-by: Kees Cook <keescook@chromium.org> # Signed-off-by: Kees Cook <keescook@chromium.org> # Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> # < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/alpha-linux/bin/alpha-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/alpha-linux/bin/alpha-linux-ld --version # < git log --format=%s --max-count=1 736116436e5b99b46e1a49c17cae6f6ee0a30e84 # < make -s -j 8 ARCH=alpha O=/kisskb/build/gustavoars_alpha-defconfig_alpha-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/alpha-linux/bin/alpha-linux- defconfig # < make -s -j 8 ARCH=alpha O=/kisskb/build/gustavoars_alpha-defconfig_alpha-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/alpha-linux/bin/alpha-linux- help # make -s -j 8 ARCH=alpha O=/kisskb/build/gustavoars_alpha-defconfig_alpha-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/alpha-linux/bin/alpha-linux- olddefconfig # make -s -j 8 ARCH=alpha O=/kisskb/build/gustavoars_alpha-defconfig_alpha-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/alpha-linux/bin/alpha-linux- <stdin>:1511:2: warning: #warning syscall clone3 not implemented [-Wcpp] WARNING: modpost: "saved_config" [vmlinux] is COMMON symbol Kernel arch/alpha/boot/vmlinux.gz is ready Completed OK # rm -rf /kisskb/build/gustavoars_alpha-defconfig_alpha-gcc4.9 # Build took: 0:01:16.021288

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