protobuf download error.

rm -rf /opt/mxe/tmp-* /opt/mxe/usr \
       ./*-*.list ./mxe-*.tar.xz ./mxe-*.deb* ./wheezy ./jessie
[check requirements]
[download]  cmake
[build nonetwork lib]
[git-log]   27facf1c Merge pull request #1659 from tonytheodore/gcc5-fix
[build]     mxe-conf               x86_64-unknown-linux-gnu
[done]      mxe-conf               x86_64-unknown-linux-gnu                                328 KiB        0m3.932s
[build]     cmake                  x86_64-unknown-linux-gnu
[done]      cmake                  x86_64-unknown-linux-gnu                                292228 KiB     2m52.132s
[download]  geoip-database
[build]     geoip-database         x86_64-unknown-linux-gnu
[done]      geoip-database         x86_64-unknown-linux-gnu                                6444 KiB       0m2.754s
[download]  gmp
[build]     gmp                    x86_64-unknown-linux-gnu
[done]      gmp                    x86_64-unknown-linux-gnu                                29380 KiB      0m28.668s
[download]  googlemock
[no-build]  googlemock             x86_64-unknown-linux-gnu
[download]  googletest
[no-build]  googletest             x86_64-unknown-linux-gnu
[download]  isl
[build]     isl                    x86_64-unknown-linux-gnu
[done]      isl                    x86_64-unknown-linux-gnu                                41696 KiB      0m24.445s
[download]  lzma
[no-build]  lzma                   x86_64-unknown-linux-gnu
[download]  mpfr
[build]     mpfr                   x86_64-unknown-linux-gnu
[done]      mpfr                   x86_64-unknown-linux-gnu                                14904 KiB      0m20.172s
[download]  mpc
[build]     mpc                    x86_64-unknown-linux-gnu
[done]      mpc                    x86_64-unknown-linux-gnu                                5572 KiB       0m6.251s
[download]  pkgconf
[build]     pkgconf                x86_64-unknown-linux-gnu
[done]      pkgconf                x86_64-unknown-linux-gnu                                1524 KiB       0m3.780s
[download]  protobuf

Download failed or wrong checksum of package protobuf!
------------------------------------------------------------
  3750K .......... .......... .......... .......... .......... 96% 21.8M 0s
  3800K .......... .......... .......... .......... .......... 97% 8.73M 0s
  3850K .......... .......... .......... .......... .......... 98%  816K 0s
  3900K .......... .......... .......... .......... .......... 99% 1.78M 0s
  3950K ......                                                100% 18.1M=2.9s
2017-11-27 18:22:01 (1.33 MB/s) - '/opt/mxe/pkg/.tmp-protobuf-3.1.0.tar.gz' saved [4051540/4051540]
+ cat /opt/mxe/pkg/.tmp-protobuf-3.1.0.tar.gz
+ rm /opt/mxe/pkg/.tmp-protobuf-3.1.0.tar.gz
------------------------------------------------------------
[log]      /opt/mxe/log/protobuf-download

Makefile:484: recipe for target 'download-only-protobuf-3.1.0.tar.gz' failed
make: *** [download-only-protobuf-3.1.0.tar.gz] Error 1