Bug Report or Feature Request (mark with an x)

- [ X ] bug report -> please search issues before submitting
- [ ] feature request

Area

- [ ] devkit
- [ ] schematics

Versions

Angular CLI: 6.0.8
Node: 9.4.0
OS: win32 x64
Angular: 6.0.7
... animations, common, compiler, compiler-cli, core, forms
... http, platform-browser, platform-browser-dynamic
... platform-server, router

@angular-devkit/architect 0.6.8
@angular-devkit/build-angular 0.6.8
@angular-devkit/build-optimizer 0.4.9
@angular-devkit/core 0.6.8
@angular-devkit/schematics 0.6.8
@angular/cdk 6.3.2
@angular/cli 6.0.8
@angular/material 6.3.2
@ngtools/webpack 6.0.8
@schematics/angular 0.6.8
@schematics/update 0.6.8
rxjs 6.2.1
typescript 2.7.2
webpack 4.8.3

Windows 10, npm version 6.1.0

Repro steps

The log given by the failure

Desired functionality

Mention any other details that might be useful

The build size with --prod used to be 6MB+, but with Angular CLI 6.0.8 (and Angular 6), the build size grew to over 48MB.

How should can I help to diagnose this, what could cause this?