Angular 9 - NGCC fails with an unhandled exception

Question

Buidling the application after having upgraded dependcies to Angular 9 (and having performed necessary code changes) throws an error:

Compiling @ang

Answer 1

In my particular case the @angular-devkit/build-angular was updated to "^0.1001.2" in my package.json after running the npm audit fix. (This version seems to belong to angular 10, instead of the local projects' angular version (v9.1.7))

After reverting this change, everything started working again :

"@angular-devkit/build-angular": "~0.901.6"