| Message ID | 20190129130146.11934-1-anders.roxell@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | btrfs: relocation: fix unused variable | expand |
On Tue, Jan 29, 2019 at 02:01:46PM +0100, Anders Roxell wrote: > When CONFIG_BRTFS_ASSERT isn't enabled, variable root_objectid isn't used. > > fs/btrfs/relocation.c: In function ‘insert_dirty_subv’: > fs/btrfs/relocation.c:2138:6: warning: unused variable ‘root_objectid’ [-Wunused-variable] > u64 root_objectid = root->root_key.objectid; > ^~~~~~~~~~~~~ > > Reworked by adding a runtime check in the assfail function instead of > the '#ifdef CONFIG_BTRFS_ASSERT #else ...", so the compiler sees the > condition being passed into an inline function after preprocessing. I've fixed the warning by avoiding the local variable but I like your fix in general, thanks.
On Tue, Jan 29, 2019 at 04:21:27PM +0100, David Sterba wrote: > On Tue, Jan 29, 2019 at 02:01:46PM +0100, Anders Roxell wrote: > > When CONFIG_BRTFS_ASSERT isn't enabled, variable root_objectid isn't used. > > > > fs/btrfs/relocation.c: In function ‘insert_dirty_subv’: > > fs/btrfs/relocation.c:2138:6: warning: unused variable ‘root_objectid’ [-Wunused-variable] > > u64 root_objectid = root->root_key.objectid; > > ^~~~~~~~~~~~~ > > > > Reworked by adding a runtime check in the assfail function instead of > > the '#ifdef CONFIG_BTRFS_ASSERT #else ...", so the compiler sees the > > condition being passed into an inline function after preprocessing. > > I've fixed the warning by avoiding the local variable but I like your > fix in general, thanks. Committed with this changelog: "btrfs: let the assertion expression compile in all configs A compiler warning (in a patch in development) pointed to a variable that was used only inside and ASSERT: u64 root_objectid = root->root_key.objectid; ASSERT(root_objectid == ...); fs/btrfs/relocation.c: In function ‘insert_dirty_subv’: fs/btrfs/relocation.c:2138:6: warning: unused variable ‘root_objectid’ [-Wunused-variable] u64 root_objectid = root->root_key.objectid; ^~~~~~~~~~~~~ When CONFIG_BRTFS_ASSERT isn't enabled, variable root_objectid isn't used. Rework the assertion helper by adding a runtime check instead of the '#ifdef CONFIG_BTRFS_ASSERT #else ...", so the compiler sees the condition being passed into an inline function after preprocessing."
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index de23a7ea396d..ad7d079f2cae 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -3521,21 +3521,18 @@ do { \ rcu_read_unlock(); \ } while (0) -#ifdef CONFIG_BTRFS_ASSERT - __cold static inline void assfail(const char *expr, const char *file, int line) { - pr_err("assertion failed: %s, file: %s, line: %d\n", - expr, file, line); - BUG(); + if (IS_ENABLED(CONFIG_BTRFS_ASSERT)) { + pr_err("assertion failed: %s, file: %s, line: %d\n", + expr, file, line); + BUG(); + } } #define ASSERT(expr) \ (likely(expr) ? (void)0 : assfail(#expr, __FILE__, __LINE__)) -#else -#define ASSERT(expr) ((void)0) -#endif /* * Use that for functions that are conditionally exported for sanity tests but
When CONFIG_BRTFS_ASSERT isn't enabled, variable root_objectid isn't used. fs/btrfs/relocation.c: In function ‘insert_dirty_subv’: fs/btrfs/relocation.c:2138:6: warning: unused variable ‘root_objectid’ [-Wunused-variable] u64 root_objectid = root->root_key.objectid; ^~~~~~~~~~~~~ Reworked by adding a runtime check in the assfail function instead of the '#ifdef CONFIG_BTRFS_ASSERT #else ...", so the compiler sees the condition being passed into an inline function after preprocessing. Fixes: 7b837199c581 ("btrfs: relocation: Delay reloc tree deletion after merge_reloc_roots()") Signed-off-by: Anders Roxell <anders.roxell@linaro.org> --- fs/btrfs/ctree.h | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) -- 2.19.2