If you have a lot of form controls in template and compile with AOT, webpack build will hang for a long time or seemingly never complete.
To demo the bug, just clone the github repo and run npm i to install.
To compile and build files, run npm run compile.
To create a normal build without ngc, just use npm run build.
To start server, use npm run prodserver.
I have 20 form controls on it right now, so it should take about 2 minutes to build. If you delete 5 of them, it should build after compile in about 12 seconds. If you put it to 30 controls, it should hang for an extremely long time or never complete.