btrfs causes four test failures

I tried running cargo test --features unix --release on my desktop and laptop and had failures on my desktop only. These installs are both exactly the same, but my desktop runs on btrfs and my laptop on ext4. They are running the most recent update of Debian 12 bookworm. This is on the most recent stable version of Rust.

Here is the output:

...
failures:

---- test_cp::test_cp_debug_reflink_auto_sparse_always_non_sparse_file_with_long_zero_sequence stdout ----
touch: /tmp/.tmp8FzIzn/a
write(append): /tmp/.tmp8FzIzn/a
write(append): /tmp/.tmp8FzIzn/a
run: /home/david/projects/coreutils/target/release/coreutils cp --debug --sparse=always a b
thread 'test_cp::test_cp_debug_reflink_auto_sparse_always_non_sparse_file_with_long_zero_sequence' panicked at tests/by-util/test_cp.rs:4046:5:
assertion `left == right` failed
  left: 40
 right: 8

---- test_cp::test_cp_sparse_always_empty stdout ----
write(default): /tmp/.tmpjXdqIm/src_file1
run: /home/david/projects/coreutils/target/release/coreutils cp --sparse=always src_file1 dst_file_sparse
open: /tmp/.tmpjXdqIm/dst_file_sparse
thread 'test_cp::test_cp_sparse_always_empty' panicked at tests/by-util/test_cp.rs:2334:9:
assertion `left == right` failed
  left: 32
 right: 0

---- test_cp::test_cp_sparse_always_non_empty stdout ----
write(default): /tmp/.tmp7HMecc/src_file1
run: /home/david/projects/coreutils/target/release/coreutils cp --sparse=always src_file1 dst_file_sparse
open: /tmp/.tmp7HMecc/dst_file_sparse
thread 'test_cp::test_cp_sparse_always_non_empty' panicked at tests/by-util/test_cp.rs:2361:5:
assertion `left == right` failed
  left: 136
 right: 16

---- test_du::test_du_dereference_args stdout ----
mkdir: /tmp/.tmpfF3pUp/dir
write(default): /tmp/.tmpfF3pUp/dir/file-ignore1
write(default): /tmp/.tmpfF3pUp/dir/file-ignore2
symlink: /tmp/.tmpfF3pUp/dir,/tmp/.tmpfF3pUp/sublink
run: /home/david/projects/coreutils/target/release/coreutils du -D -s sublink
run: /home/david/projects/coreutils/target/release/coreutils du -H -s sublink
run: /home/david/projects/coreutils/target/release/coreutils du --dereference-args -s sublink
run: /home/david/projects/coreutils/target/release/coreutils du -s sublink
thread 'test_du::test_du_dereference_args' panicked at tests/by-util/test_du.rs:367:12:
'4	sublink
' does not contain '0	sublink
'


failures:
    test_cp::test_cp_debug_reflink_auto_sparse_always_non_sparse_file_with_long_zero_sequence
    test_cp::test_cp_sparse_always_empty
    test_cp::test_cp_sparse_always_non_empty
    test_du::test_du_dereference_args

test result: FAILED. 3384 passed; 4 failed; 57 ignored; 0 measured; 0 filtered out; finished in 33.95s

Reproduce the failures with cargo test --features unix --release on the reported btrfs setup, then compare the results with ext4. Read the failing cases in tests/by-util/test_cp.rs at lines 2334, 2361, and 4046, and tests/by-util/test_du.rs at line 367. Done means all four reported tests pass on btrfs without regressing the existing test suite.