The '-- \n2.54.0\n\n' trailer added in 989b884 was wrong. The
underlying problem was the malformed @@ hunk counts (off by 1 in
both old and new), fixed in a840f76. With correct @@ counts, patch(1)
processes the hunk fully and then sees the orphan trailer at EOF —
which it tries to parse as the start of a new patch header
('malformed patch at line N: 2.54.0').
The original (no-trailer) shape works correctly in the concatenated
cumulative as long as the @@ counts are right. Removing the trailer
brings the file back to the original 1562-byte size and the
cumulative b2sum to 334c37b5d37067982bd9... (size unchanged 157 458 ->
157 446 since the 12 byte trailer is gone).
Lesson for ka-promote: when concatenating patches as a stream for
patch(1), the LAST patch must not carry a trailing '-- \n<version>\n'
sentinel — the previous patches' sentinels are fine because they are
followed by 'From <sha>' headers that patch(1) recognises as the next
patch boundary. Documented in series-dir README as a gotcha.
claude-noether
84734ba527