Loader breaks build - non-existant errors are reported at invalid places (tsc alone compiles project just fine)

[mnn]

(I am total newbie concerning TypeScript and Webpack. I already asked at TypeScript and they pointed out that TS compiler is working well and it must be something at higher layers which breaks error reporting/build.)

Running TS compiler alone works fine (./node_modules/.bin/tsc -p . --pretty --outDir out reports 4 valid errors, explained bellow), but when run via webpack mysterious errors appear.

Here is a repro:

• seed I am using - https://github.com/preboot/angular2-webpack/tree/bf87ed9585c71be5f9aeb44243130039dcf3bc5e
• added more compiler options to tsconfig.json:

  "noImplicitAny": true,
  "noImplicitReturns": true,
  "noImplicitThis": true,
  "strictNullChecks": true,
  "forceConsistentCasingInFileNames": true,
  "skipLibCheck": true

• run npm start

Please note there is a few errors which are valid (those in app.module.ts). 19 of 22 reported errors are invalid, reported in non-existing places. (Error in api.service.spec.ts reported by tsc is not printed, probably because only used files for build are compiled?)

Example (the path is in my source, not in some library):

[default] /xxx/src/main.ts:11:96
    Index signature of object type implicitly has an 'any' type.
...
[default] /xxx/src/main.ts:11:853
    Parameter 'store' implicitly has an 'any' type.

My main.ts:

import { enableProdMode } from '@angular/core';
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { AppModule } from './app/app.module';

// depending on the env mode, enable prod mode or add debugging modules
if (process.env.ENV === 'build') {
  enableProdMode();
}

export function main() {
  return platformBrowserDynamic().bootstrapModule(AppModule);
}

if (document.readyState === 'complete') {
  main();
} else {
  document.addEventListener('DOMContentLoaded', main);
}

It sure looks like those are type errors in libraries, which is very odd because of "skipLibCheck": true. Also if it is already concatenated in one source, why it is not ES5 as config specifies? I am really confused by all this.

[mnn]

Still broken.

Now tested with these versions:

├── awesome-typescript-loader@3.0.0-beta.17 
└── typescript@2.1.4 

[mnn]

Problem persists. Tested with newest versions:

├── awesome-typescript-loader@3.0.4 
├── typescript@2.1.6 
└── webpack@2.2.1 

[mnn]

Still broken. :disappointed: All packages in test repo updated to current version just now.

[mnn]

Aaand ... still broken. Updated all packages just now. Versions:

├── awesome-typescript-loader@3.2.3
├── typescript@2.4.2
├── webpack@3.5.5

[mnn]

Issue still persists with updated packages. test repo: https://github.com/mnn/angular2-webpack/

├── awesome-typescript-loader@3.4.1
├── typescript@2.6.2
├── webpack@3.10.0