Why does ng build --prod fail, while ng build succeeds?

Question

I am new to angular and started to build an application with Angular 7 and angular-material. ng serve and ng build work well. But when I start ng build --prod it gives me the below error.

Thanks for any response. Any ides will be highly appreciated.

package.json

 "dependencies": {
    "@angular/animations": "^7.1.0",
    "@angular/cdk": "^7.1.0",
    "@angular/common": "~7.1.0",
    "@angular/compiler": "~7.1.0",
    "@angular/core": "~7.1.0",
    "@angular/forms": "~7.1.0",
    "@angular/material": "^7.1.0",
    "@angular/platform-browser": "~7.1.0",
    "@angular/platform-browser-dynamic": "~7.1.0",
    "@angular/router": "~7.1.0",
    "angular-hammer": "^2.2.0",
    "core-js": "^2.5.4",
    "font-awesome": "^4.7.0",
    "jquery": "^3.3.1",
    "rxjs": "~6.3.3",
    "tslib": "^1.9.0",
    "zone.js": "~0.8.26"
  },
  "devDependencies": {
    "@angular-devkit/build-angular": "~0.11.0",
    "@angular/cli": "~7.1.0",
    "@angular/compiler-cli": "~7.1.0",
    "@angular/language-service": "~7.1.0",
    "@types/node": "~8.9.4",
    "@types/jasmine": "~2.8.8",
    "@types/jasminewd2": "~2.0.3",
    "codelyzer": "~4.5.0",
    "jasmine-core": "~2.99.1",
    "jasmine-spec-reporter": "~4.2.1",
    "karma": "~3.1.1",
    "karma-chrome-launcher": "~2.2.0",
    "karma-coverage-istanbul-reporter": "~2.0.1",
    "karma-jasmine": "~1.1.2",
    "karma-jasmine-html-reporter": "^0.2.2",
    "protractor": "~5.4.0",
    "ts-node": "~7.0.0",
    "tslint": "~5.11.0",
    "typescript": "~3.1.6"

  imports: [
    BrowserModule,
    AppRoutingModule,
    ReactiveFormsModule,
    HttpClientModule,
    MatDialogModule,
    MatChipsModule,
    BrowserAnimationsModule,
    MatTooltipModule,
    MatDialogModule,
    MatSelectModule,
    MatBadgeModule,
    MatButtonToggleModule,
    MatSlideToggleModule,
    MatTableModule,
    MatExpansionModule,
    MatDividerModule
  ],
  providers: [fakeBackendProvider,
 //   { provide: HTTP_INTERCEPTORS, useClass: JwtInterceptor, multi: true },
 //   { provide: HTTP_INTERCEPTORS, useClass: ErrorInterceptor, multi: true }
],
  bootstrap: [AppComponent],
  entryComponents: [SonderdetailsComponent, UmlaufdetailsComponent]

I get following error:

ERROR in Error during template compile of 'MatDialogContainer'
  Function calls are not supported in decorators but 'trigger' was called in 'matDialogAnimations'
    'matDialogAnimations' calls 'trigger' at 
    @angular\material\dialog\typings\index.ts(38,20)

Answer 1

Still dont know the answer, but i tried the same at a different computer. The second one was not behind a proxy and the build succeded. So it deffinetly has something to do with the proxy. But as long as I can build my project, this problem is not so important anymore.

Thanks for the responses.