4.20-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit a52c5a16cf19d8a85831bb1b915a221dd4ffae3c ]
There are several warnings from Clang about no case statement matching the constant 0:
In file included from drivers/block/drbd/drbd_receiver.c:48: In file included from drivers/block/drbd/drbd_int.h:48: In file included from ./include/linux/drbd_genl_api.h:54: In file included from ./include/linux/genl_magic_struct.h:236: ./include/linux/drbd_genl.h:321:1: warning: no case matching constant switch condition '0' GENL_struct(DRBD_NLA_HELPER, 24, drbd_helper_info, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ./include/linux/genl_magic_struct.h:220:10: note: expanded from macro 'GENL_struct' switch (0) { ^
Silence this warning by adding a 'case 0:' statement. Additionally, adjust the alignment of the statements in the ct_assert_unique macro to avoid a checkpatch warning.
This solution was originally sent by Arnd Bergmann with a default case statement: https://lore.kernel.org/patchwork/patch/756723/
Link: https://github.com/ClangBuiltLinux/linux/issues/43 Suggested-by: Lars Ellenberg lars.ellenberg@linbit.com Signed-off-by: Nathan Chancellor natechancellor@gmail.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- include/linux/genl_magic_struct.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/include/linux/genl_magic_struct.h b/include/linux/genl_magic_struct.h index 5972e4969197..eeae59d3ceb7 100644 --- a/include/linux/genl_magic_struct.h +++ b/include/linux/genl_magic_struct.h @@ -191,6 +191,7 @@ static inline void ct_assert_unique_operations(void) { switch (0) { #include GENL_MAGIC_INCLUDE_FILE + case 0: ; } } @@ -209,6 +210,7 @@ static inline void ct_assert_unique_top_level_attributes(void) { switch (0) { #include GENL_MAGIC_INCLUDE_FILE + case 0: ; } } @@ -218,7 +220,8 @@ static inline void ct_assert_unique_top_level_attributes(void) static inline void ct_assert_unique_ ## s_name ## _attributes(void) \ { \ switch (0) { \ - s_fields \ + s_fields \ + case 0: \ ; \ } \ }