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>> /var/tmp/portage/sys-kernel/gentoo-kernel-6.5.9/work/linux-6.5/fs/btrfs/scrub.c:2040:21: note: ‘found_logical’ was declared here >>   2040 |                 u64 found_logical; >>        |                     ^~~~~~~~~~~~~ >> ``` > > Good find! found_logical is passed by reference to > queue_scrub_stripe(..) (inlined) > where it is used without ever being set: > > ... >     /* Either >0 as no more extents or <0 for error. */ >     if (ret) >         return ret; >     if (found_logical_ret) >         *found_logical_ret = stripe->logical; >     sctx->cur_stripe++; > ... > > Something is missing here, and somehow I don't think it's just the > top-level > initialisation of found_logical. This looks like a false alert for me. @found_logical is intentionally uninitialized to catch any uninitialized usage by compiler. It would be set by queue_scrub_stripe() when there is any stripe found. If there is no stripe found, queue_scrub_stripe() would return >0, then we know there is no more extent and break the loop. If there is any error, we error out too, thus no problem with that. So to me this looks like a false alert. Mind to share the compiler and its version? Thanks, Qu > > -h