f fix warning

Author: TheBlueMatt

lightning/src/debug_sync.rs

@@ -65,7 +65,7 @@ static LOCKS_INIT: Once = Once::new();
 struct LockMetadata {
 	lock_idx: u64,
 	locked_before: StdMutex<HashSet<LockDep>>,
-	lock_construction_bt: Backtrace,
+	_lock_construction_bt: Backtrace,
 }
 impl PartialEq for LockMetadata {
 	fn eq(&self, o: &LockMetadata) -> bool { self.lock_idx == o.lock_idx }
@@ -132,7 +132,7 @@ impl LockMetadata {
 		let res = Arc::new(LockMetadata {
 			locked_before: StdMutex::new(HashSet::new()),
 			lock_idx,
-			lock_construction_bt: backtrace,
+			_lock_construction_bt: backtrace,
 		});
 
 		#[cfg(feature = "backtrace")]
@@ -168,7 +168,7 @@ impl LockMetadata {
 				for locked_dep in locked.locked_before.lock().unwrap().iter() {
 					if locked_dep.lock == *this && locked_dep.lock != *locked {
 						#[cfg(feature = "backtrace")]
-						panic!("Tried to violate existing lockorder.\nMutex that should be locked after the current lock was created at the following backtrace.\nNote that to get a backtrace for the lockorder violation, you should set RUST_BACKTRACE=1\nLock constructed at:\n{:?}\n\nLock dep created at:\n{:?}\n\n", locked.lock_construction_bt, locked_dep.lockdep_trace);
+						panic!("Tried to violate existing lockorder.\nMutex that should be locked after the current lock was created at the following backtrace.\nNote that to get a backtrace for the lockorder violation, you should set RUST_BACKTRACE=1\nLock constructed at:\n{:?}\n\nLock dep created at:\n{:?}\n\n", locked._lock_construction_bt, locked_dep.lockdep_trace);
 						#[cfg(not(feature = "backtrace"))]
 						panic!("Tried to violate existing lockorder. Build with the backtrace feature for more info.");
 					}