On Tue, 2019-10-22 at 10:01 +0300, Nikolay Borisov wrote: > > On 22.10.19 г. 9:59 ч., Nikolay Borisov wrote: > > > > > > On 22.10.19 г. 5:02 ч., Marcos Paulo de Souza wrote: > >> From: Marcos Paulo de Souza <mpdeso...@suse.com> > >> > >> When compiling with clang, this warning is shown: > >> > >> common/utils.c:404:3: warning: declaration does not declare > anything [-Wmissing-declarations] > >> __attribute__ ((fallthrough)); > >> > >> This attribute seems to silence the same warning in GCC. Changing > this > >> attribute with /* fallthrough */ fixes the warning for both gcc > and > >> clang. > >> > >> Signed-off-by: Marcos Paulo de Souza <mpdeso...@suse.com> > > > > Which clang version are you using? According to > > https://clang.llvm.org/docs/AttributeReference.html#fallthrough > this > > attribute is supported even with the GNU syntax. > > Looking at the documentation the gnu syntax is supported in the > 'current' / 10, unreleased version. All others, up to version 9 does > not > support this syntax.
I'm using the default clang in Tumbleweed (20191009): clang --version clang version 8.0.1 (tags/RELEASE_801/final 366581) > > > > >> --- > >> common/utils.c | 12 ++++++------ > >> 1 file changed, 6 insertions(+), 6 deletions(-) > >> > >> diff --git a/common/utils.c b/common/utils.c > >> index 2cf15c33..a88336b3 100644 > >> --- a/common/utils.c > >> +++ b/common/utils.c > >> @@ -401,15 +401,15 @@ int pretty_size_snprintf(u64 size, char > *str, size_t str_size, unsigned unit_mod > >> case UNITS_TBYTES: > >> base *= mult; > >> num_divs++; > >> - __attribute__ ((fallthrough)); > >> + /* fallthrough */ > >> case UNITS_GBYTES: > >> base *= mult; > >> num_divs++; > >> - __attribute__ ((fallthrough)); > >> + /* fallthrough */ > >> case UNITS_MBYTES: > >> base *= mult; > >> num_divs++; > >> - __attribute__ ((fallthrough)); > >> + /* fallthrough */ > >> case UNITS_KBYTES: > >> num_divs++; > >> break; > >> @@ -1135,14 +1135,14 @@ int test_num_disk_vs_raid(u64 > metadata_profile, u64 data_profile, > >> default: > >> case 4: > >> allowed |= BTRFS_BLOCK_GROUP_RAID10; > >> - __attribute__ ((fallthrough)); > >> + /* fallthrough */ > >> case 3: > >> allowed |= BTRFS_BLOCK_GROUP_RAID6; > >> - __attribute__ ((fallthrough)); > >> + /* fallthrough */ > >> case 2: > >> allowed |= BTRFS_BLOCK_GROUP_RAID0 | > BTRFS_BLOCK_GROUP_RAID1 | > >> BTRFS_BLOCK_GROUP_RAID5; > >> - __attribute__ ((fallthrough)); > >> + /* fallthrough */ > >> case 1: > >> allowed |= BTRFS_BLOCK_GROUP_DUP; > >> } > >>
