[bug] CLANG_ENABLE_MODULES = YES -- creates broken metadata

[NathanaelA]

Environment

• Using XCode 12.x
• NS 7.x

Issue

Metadata generation seems to be faulty if the CLANG_ENABLE_MODULES = YES

Steps (flavor doesn't matter):

• tns create test --js
• cd App_Resouces/ios
• edit build.xcconfig
  • Add CLANG_ENABLE_MODULES = YES
  • Save
• cd ../..
• ns build ios --for-device

The resulting metadata

Result: 19159 declarations from 40 top level modules
Size of Metadata file (platforms/ios/build/Debug-iphoneos/) is ~1.3m

Normal application without CLANG_ENABLE_MODULES reports:

Result: 45930 declarations from 155 top level modules
Size of Metadata file is ~6.4m

[kl4n4]

+1 we experience the same issue. Is this no longer supported or is this gonna be fixed in the near future?

[NathanaelA]

To set your expectation properly; this is a lower backlog priority bug, and has very little priority. Most people in the community should never run into it as they won't set this value.

I would love to know why you have used this value and what it was solving for you, as I honestly couldn't figure out why I would want to use this flag; just ran into a client who tried it and the app was crashing on startup, and figured I should document it as a known issue.

Since this is a open source project, we do :heart: :heart: :heart: PR's. Finally, if you really need to use this flag and you don't want to spend the time digging into fix it and creating a PR -- you can hire nStudio (and other companies in the community) to fix this as a project for you.

[kkoates]

+1 I've hit this now too. I have a 3rd party framework that I'm creating a plugin for that is importing a module that requires CLANG_ENABLE_MODULES = YES. Without turning this on I get the standard errors to turn modules on due to @import being used to include their module. Upon adding CLANG_ENABLE_MODULES = YES to build.xcconfig, ns builds okay but app crashes on launch for a real device. It builds and runs without crash on simulator and the framework works as expected.

Using XCode 12.5 NS CLI 8.0.1 NS 6 (tns-ios 6.5.4)

If anyone has any tips on a way around needing CLANG_ENABLE_MODULES on I'm all ears. I'll follow up if I find something beneficial.