[question] git svn fail to fetch GCC source due to index mismatch

HI:
   I have problem when use git svn fetch command to
retrieve the GCC source code.
It says index mismatch, then  abort,  any suggestion?

  
$git svn fetch
Index mismatch: 98ba56dbceddf50ebfab9e4649e9b1b1a319b377 !=
4f40f4619690f89454614be0eba63d584d25523e
rereading 19e22aa4cbc9f7e3667243481f33c859e3bba358
Found possible branch point: svn://gcc.gnu.org/svn/gcc/trunk =>
svn://gcc.gnu.org/svn/gcc/trunk, 130802
Initializing parent: git-svn@130802
Found branch parent: (git-svn) 9a08076e1ad241080838d547f64a2a9aceb083ca
Index mismatch: 4f40f4619690f89454614be0eba63d584d25523e !=
98ba56dbceddf50ebfab9e4649e9b1b1a319b377
rereading 9a08076e1ad241080838d547f64a2a9aceb083ca
Following parent with do_switch
Malformed network data: Malformed network data at
/usr/libexec/git-core/git-svn line 2340

$git branch -a
git-svn
git-svn@130802