"John Cai via GitGitGadget" <gitgitgadget@xxxxxxxxx> writes:
> This is happening because on a fast foward with an oid as a <branch>,
> update_refs() will only call update_ref() with REF_NO_DEREF if
> RESET_HEAD_DETACH is set. This change was made in 176f5d96 (built-in rebase
> --autostash: leave the current branch alone if possible,
> 2018-11-07). In rebase, we are not setting the RESET_HEAD_DETACH flag,
> which means that the update_ref() call ends up dereferencing
> HEAD and updating it to the oid used as <branch>.
>
> The correct behavior is that git rebase should update HEAD to $(git
> rev-parse topic) without dereferencing it.
It is unintuitive that unconditionally setting the RESET_HEAD_DETACH
bit is the right solution.
If the command weren't "rebase master side^0" but "rebase master
side", i.e. "please rebase the side branch itself, not an unnamed
branch created out of the side branch, on master", according to
<reset.h>, we ought to end up being on a detached HEAD, as
reset_head() with the bit
/* Request a detached checkout */
#define RESET_HEAD_DETACH (1<<0)
requests a detached checkout. But that apparently is not what would
happen with your patch applied.
Puzzled. The solution to the puzzle probably deserves to be in the
proposed log message.
Thanks.
