"Argument list too long" in git remote update (Was: Git and GCC)

> After the discussions lately regarding the gcc svn mirror.  I'm coming
> up with a recipe to set up your own git-svn mirror.  Suggestions on  
> the
> following.
>
> // Create directory and initialize git
> mkdir gcc
> cd gcc
> git init
> // add the remote site that currently mirrors gcc
> // I have chosen the name gcc.gnu.org *1* as my local name to refer to
> // this choose something else if you like
> git remote add gcc.gnu.org git://git.infradead.org/gcc.git
> // fetching someone else's remote branches is not a standard thing  
> to do
> // so we'll need to edit our .git/config file
> // you should have a section that looks like:
> [remote "gcc.gnu.org"]
>        url = git://git.infradead.org/gcc.git
>        fetch = +refs/heads/*:refs/remotes/gcc.gnu.org/*
> // infradead's mirror puts the gcc svn branches in its own namespace
> // refs/remotes/gcc.gnu.org/*
> // change our fetch line accordingly
> [remote "gcc.gnu.org"]
>        url = git://git.infradead.org/gcc.git
>        fetch = +refs/remotes/gcc.gnu.org/*:refs/remotes/gcc.gnu.org/*
> // fetch the remote data from the mirror site
> git remote update