Just note here that the build.json file should look like this :

  "ios": {
    "release": {
      "buildFlag": [
        "-UseModernBuildSystem=0"
      ]
    }
  }

not

  "iOS": {
    "release": {
      "buildFlag": [
        "-UseModernBuildSystem=0"
      ]
    }
  }

like "mentioned" in the previous comment ;p

Thanks, @dpogue
I was really wondering about the workaround. Hope to fix it soon!
Cheers

is this why im getting this issue

ERROR ITMS-90174: "Missing Provisioning Profile - Apps must contain a provisioning profile in a file named embedded.mobileprovision."

is there a workaround ?

@neofuture I am also encountering this after upgrading to XCode 10

Then open an issue please that has all available information on these failures @neofuture and @aceoliver. Thanks.

@dpogue Thanks! The answer solved my problem.

@sambegin Thanks for the workaround. Where is this build.json file is present in the app directory structure?

Btw this worked for me:
ionic cordova build ios -- --buildFlag="-UseModernBuildSystem=0"

@jeffreyramia with the help of your answer I am able to build an app but whenever I am trying to emulate it gives me an error as "platforms/ios/build/emulator/demo APP.app/Info.plist file not found.
[ERROR] An error occurred while running subprocess cordova."

If you use pure cordova ios, you can run like:

cordova run --target='iPad-Air-2' --buildFlag='-UseModernBuildSystem=0'

It is still currently in the middle of the release process. It is recommended to wait until it is released on NPM.

@erisu My apologies. I assumed once it was tagged here we were good to go.

@dpogue you sir won the internet today!!!

Not to tick anyone off or insult anyone or the effort into making 5.0.0 happen, but how tested is the latest release - or can we all ignore my inquiry and just thank Apple for forcing us into bleeding edge?

For the record....its stuff like this...and a gazillion other things about Apple that tick me off. Nothing but a bunch of rotten Apples.

cordova-ios@5.0.0 is now officially released to NPM.

Here is also the Cordova iOS 5.0.0 Release Blog Post.

Thanks to everyone involved!

Good to hear. Thanks. It is really appreciated for your hard work.

I'm slightly confused about the release. Does it mean if I update to 5.0.0, using UseModernBuildSystem=0 is no longer required?

Thanks!

I'm slightly confused about the release. Does it mean if I update to 5.0.0, using UseModernBuildSystem=0 is no longer required?

That's correct

@dpogue It seems as though setting UseModernBuildSystem=1 is still behaving like it used to, even after upgrading to 5.0.0. Can you show a sample output of a build process using the new build system?

After adding cordova-ios@5.0.0, can't add onesingal plugin.

It shows this issue:

cordova plugin add onesignal-cordova-plugin --save
Installing "onesignal-cordova-plugin" for ios
"framework" tag with type "podspec" is deprecated and will be removed. Please use the "podspec" tag.
Failed to install 'onesignal-cordova-plugin': undefined
CordovaError: Promise rejected with non-error: '/Library/Ruby/Gems/2.3.0/gems/claide-1.0.2/lib/claide/command.rb:439:in help!\': \u001b[31m[!] You cannot run CocoaPods as root.\u001b[39m (CLAide::Help)\n\n\u001b[4mUsage:\u001b[24m\n\n $ \u001b[32mpod\u001b[39m \u001b[32mCOMMAND\u001b[39m\n\n CocoaPods, the Cocoa library package manager.\n\n\u001b[4mCommands:\u001b[24m\n\n \u001b[32m+ cache\u001b[39m Manipulate the CocoaPods cache\n \u001b[32m+ env\u001b[39m Display pod environment\n \u001b[32m+ init\u001b[39m Generate a Podfile for the current directory\n \u001b[32m+ install\u001b[39m Install project dependencies according to versions from a\n Podfile.lock\n \u001b[32m+ ipc\u001b[39m Inter-process communication\n \u001b[32m+ lib\u001b[39m Develop pods\n \u001b[32m+ list\u001b[39m List pods\n \u001b[32m+ outdated\u001b[39m Show outdated project dependencies\n \u001b[32m+ repo\u001b[39m Manage spec-repositories\n \u001b[32m+ setup\u001b[39m Setup the CocoaPods environment\n \u001b[32m+ spec\u001b[39m Manage pod specs\n \u001b[32m+ update\u001b[39m Update outdated project dependencies and create new Podfile.lock\n\n\u001b[4mOptions:\u001b[24m\n\n \u001b[34m--silent\u001b[39m Show nothing\n \u001b[34m--version\u001b[39m Show the version of the tool\n \u001b[34m--verbose\u001b[39m Show more debugging information\n \u001b[34m--no-ansi\u001b[39m Show output without ANSI codes\n \u001b[34m--help\u001b[39m Show help banner of specified command\n\tfrom /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.6.0/lib/cocoapods/command.rb:47:in run'\n\tfrom /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.6.0/bin/pod:55:in <top (required)>\'\n\tfrom /usr/local/bin/pod:22:in load'\n\tfrom /usr/local/bin/pod:22:in `

'\n'
at cli.catch.err (/usr/local/lib/node_modules/cordova/bin/cordova:30:15)
at process._tickCallback (internal/process/next_tick.js:68:7)
[ERROR] An error occurred while running subprocess cordova.

    cordova plugin add onesignal-cordova-plugin --save exited with exit code 1.
    
    Re-running this command with the --verbose flag may provide more information.

Firstly, [!] You cannot run CocoaPods as root.
Secondly, Cocoapod support was refactored in cordova-ios 5.0.0, which is one of the reasons it's a major version bump. Some plugins might not (yet) be compatible with it.

I'm going to lock discussion on this issue, since it is closed. Please open new issues for problems that you find with cordova-ios@5.0.0.