I tried to install python3.6.4 on OSX 10.13.2.  I followed the Build Instructions in the README.rst:

    ./configure
    make
    make test
    sudo make install

After ./configure step, the end of the output said:

---
If you want a release build with all stable optimizations active (PGO, etc),
please run ./configure --enable-optimizations
---

So I did:

~/Downloads/Python-3.6.4$ ./configure --enable-optimizations

Next, I did:

~/Downloads/Python-3.6.4$ make

But the make step always hangs on the line:
       
      ...
      ...
      0:00:18 load avg: 2.10 [ 23/406] test_asyncgen
      0:00:19 load avg: 2.10 [ 24/406] test_asynchat
      0:00:21 load avg: 2.01 [ 25/406] test_asyncio


During the make step, OSX prompts me whether to allow incoming connections.  I've tried it both ways: Deny and Allow, but the install allows hangs on the test_asyncio line.  I hit Ctrl+C to quit the install.  One time, I waited over an hour and the install was still hanging.