On Wed, Nov 28, 2018 at 09:33:50AM +0800, Qu Wenruo wrote: > On 2018/11/28 上午3:53, David Sterba wrote: > > This is motivated by a merging mistake that happened a few releases ago. > > Two patches updated BTRFS_FS_* flags independently to the same value, > > git did not see any direct merge conflict. The two values got mixed at > > runtime and caused crash. > > > > Update all #define sequential values, the above merging problem would > > not happen as there would be a conflict and the enum value > > auto-increment would prevent duplicated values anyway. > > Just one small question for the bitmap usage. > > For enum we won't directly know the last number is, my concern is if > we're using u16 as bitmap and there is some enum over 15, will we get a > warning at compile time or some bug would just sneak into kernel?
Do you have a concrete example where this would happen? Most bits are used in 'long' that should be at least 32. I'm not aware of 16bit bits flags.
