git-svn clone fails "fatal: Not a valid object name"

Whilst doing git svn clone -s https://svn.example.com/repo/ I received the following output:

r3073 = a6132f3a937b632015e66d694250da9f606b8333 (refs/remotes/trunk)
Found possible branch point: https://svn.example.com/repo/trunk => https://svn.example.com/repo/branches/v1.3, 3073
W: Refspec glob conflict (ref: refs/remotes/trunk):
expected path: repo/branches/trunk
    real path: repo/trunk
Continuing ahead with repo/trunk
W: Refspec glob conflict (ref: refs/remotes/trunk):
expected path: repo/branches/trunk
    real path: repo/trunk
Continuing ahead with repo/trunk
W: Refspec glob conflict (ref: refs/remotes/trunk):
expected path: repo/branches/trunk
    real path: repo/trunk
Continuing ahead with repo/trunk
W: Refspec glob conflict (ref: refs/remotes/trunk):
expected path: repo/branches/trunk
    real path: repo/trunk
Continuing ahead with repo/trunk
fatal: Not a valid object name refs/remotes/tags/Sync Controllers
cat-file commit refs/remotes/tags/Sync Controllers: command returned error: 128

Running git branch -a gives:

remotes/tags/Sync%20Controllers
remotes/tags/v1.1
remotes/trunk
remotes/v1.2

I think the problem is that "remotes/tags/Sync Controllers" != "remotes/tags/Sync%20Controllers".

Solution

The tag on SVN has a space in it, but the tag in git had this space converted to %20 (URL encoded). To solve it just manually add a new tag with the verbatim name:

cd .git/refs/remotes/tags/
mv Sync%20Controllers Sync\ Controllers

Then run the git svn clone command again.

(Normally you'd do this with git tag OLDTAG NEWTAG but git was not allowing me to define a tag with a space in. The tag files are simply text files containing the hash of the relevant commit.)