Versions

Angular CLI: 6.0.0
Node: 10.0.0
OS: win32 x64
Angular: ...

Package                           Version
-----------------------------------------------------------
@angular-devkit/architect         0.6.0
@angular-devkit/core              0.6.0
@angular-devkit/schematics        0.6.0
@schematics/angular               0.6.0
@schematics/update                0.6.0
rxjs                              6.1.0
typescript                        2.7.2

Repro steps

1. Create new Angular 6 project with "ng new app-test" command.
2. Run "ng build ---prod" command.
3. Host the "dist" generated folder on a http server, such as "http-server" (https://www.npmjs.com/package/http-server).
4. Open the url in Chrome.

Observed behavior

Error: Uncaught ReferenceError: Must call super constructor in derived class before accessing 'this' or returning from derived constructor.

If you change the optimization property from true to false in the angular.json file, and repeat the above steps, the application loads normally.

Desired behavior

The application should load correctly using optimization: true.