On Friday, July 23, 2021 10:14:46 PM CEST Suren Baghdasaryan wrote: > On Fri, Jul 23, 2021 at 1:05 PM Fabio M. De Francesco > > <fmdefrancesco@xxxxxxxxx> wrote: > > Remove variable 'inode' tnat is set but unused. Issue detected > > by building with warning option -Wunused-but-set-variable. > > > > [...] > > > > - inode = file_inode(vmfile); > > > > lockdep_set_class(&inode->i_rwsem, &backing_shmem_inode_class); > > How about its usage in the above lockdep_set_class(&inode->i_rwsem, > ...) call? I'm sorry. I didn't notice that 'inode' is used soon after assignment, just in the line that follows it. I was also too confident that rebuilding the driver would have triggered an error if it is used somewhere else. I was obviously wrong. Furthermore, I usually automatically search with grep or other tools for other occurrences of a symbol in the function and the file, but this time I must have forgotten to do that. > I'm guessing you are building with CONFIG_LOCKDEP=n. Actually my .config sets CONFIG_LOCKDEP_SUPPORT=y. Did you refer to this? There is no CONFIG_LOCKDEP in the file. I've just run "make clean && make C=2 -j8 drivers/staging/android/ W=1" one more time and it still builds. How is it possible that the code builds correctly with my configuration? This is the output (the last two lines) of 'make': CC drivers/staging/android/ashmem.o AR drivers/staging/android/built-in. There are no errors or warnings, even with that "lockdep_set_class(&inode- >i_rwsem, &backing_shmem_inode_class);" left as-is after 'inode' removal. I really can't understand what I'm missing. > Have you tried adding __maybe_unused in inode variable definition to > get rid of the warning? > Actually, I didn't know that directive that you mention. I'll read the documentation and, if and where suited, I'll use it. Thanks, Fabio > > > [...] > > -- > > 2.32.0
