Cross build with `-Zbuild-std` for `x86_64-unknown-freebsd` got failed linking error.

Detail message like below:
```
error: linking with `x86_64-unknown-freebsd13-gcc.sh` failed: exit status: 1
...
          /usr/local/lib/gcc/x86_64-unknown-freebsd13/6.4.0/../../../../x86_64-unknown-freebsd13/bin/ld: final link failed: bad value
          collect2: error: ld returned 1 exit status
```
What's wrong and how to fix it?