You asked me to pull without telling me

~/git/swfed$ git pull
You asked me to pull without telling me which branch you
want to merge with, and 'branch..merge' in
your configuration file does not tell me either.  Please
name which branch you want to merge on the command line and
try again (e.g. 'git pull <repository> <refspec>').
See git-pull(1) for details on the refspec.

If you often merge with the same branch, you may want to
configure the following variables in your configuration
file:

    branch..remote = <nickname>
    branch..merge = <remote-ref>
    remote.<nickname>.url = <url>
    remote.<nickname>.fetch = <refspec>

See git-config(1) for details.

solve

~/git/swfed$ git  branch -a
* (no branch)
  depthrenum
  master
  origin/HEAD
  origin/master

branch が何時の間にか外れてました ('A`)

~/git/swfed$ git checkout master
Switched to branch "master"
Your branch is behind the tracked remote branch 'origin/master' by 1 commit,
and can be fast-forwarded.
~/git/swfed$ git pull
Updating 1e8ee43..a3d7628
Fast forward
 src/swf_tag_shape.c |   55 +++++++++++++++++++++++++++++++++++++++-----------
 1 files changed, 43 insertions(+), 12 deletions(-)

git tag で checkout した状態で git pull するとこうなるらしい。
その時はエラーになったので、それが原因とは思わなかった。