+
+sub check_upgrade_needed {
+ my $old = eval {
+ my $pid = open my $child, '-|';
+ defined $pid or croak $!;
+ if ($pid == 0) {
+ close STDERR;
+ exec('git-rev-parse',"$GIT_SVN-HEAD") or croak $?;
+ }
+ my @ret = (<$child>);
+ close $child or croak $?;
+ die $? if $?; # just in case close didn't error out
+ return wantarray ? @ret : join('',@ret);
+ };
+ return unless $old;
+ my $head = eval { safe_qx('git-rev-parse',"refs/remotes/$GIT_SVN") };
+ if ($@ || !$head) {
+ print STDERR "Please run: $0 rebuild --upgrade\n";
+ exit 1;
+ }
+}
+