ios - Xcode build failed due to concurrent builds, will retry in 2 seconds in Flutter

Question

I'm trying to run my application with iPhone and simulators. But, the application only launched on one device and when I tried to run the app with another device there they give an error:

Is there a solution for this? It's essential for development.. the most important features for us. We can't test user interactivity or UI scales at the same time and it really sucks.

This is the error that I received when I tried to run the app in Android Studio.

Launching lib/main.dart on my’s iPhone in debug mode...
Signing iOS app for device deployment using developer identity: "Apple Development: test (AMNDNA32NX)"
Running Xcode build...
Xcode build failed due to concurrent builds, will retry in 2 seconds.
Xcode build failed due to concurrent builds, will retry in 4 seconds.
Xcode build failed due to concurrent builds, will retry in 8 seconds.
Xcode build failed due to concurrent builds, will retry in 16 seconds.
Xcode build failed due to concurrent builds, will retry in 32 seconds.

This is my flutter doctor

mac@my-iMac Flutter_myapp % flutter doctor -v
[?] Flutter (Channel stable, 1.22.5, on Mac OS X 10.15.7 19H2 darwin-x64, locale en-GB)
    ? Flutter version 1.22.5 at /Users/mac/Development/flutter
    ? Framework revision 7891006299 (6 weeks ago), 2020-12-10 11:54:40 -0800
    ? Engine revision ae90085a84
    ? Dart version 2.10.4

 
[?] Android toolchain - develop for Android devices (Android SDK version 30.0.3)
    ? Android SDK at /Users/mac/Library/Android/sdk
    ? Platform android-30, build-tools 30.0.3
    ? Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    ? Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6915495)
    ? All Android licenses accepted.

[?] Xcode - develop for iOS and macOS (Xcode 12.0)
    ? Xcode at /Applications/Xcode.app/Contents/Developer
    ? Xcode 12.0, Build version 12A7209
    ? CocoaPods version 1.10.0

[!] Android Studio (version 4.1)
    ? Android Studio at /Applications/Android Studio.app/Contents
    ? Flutter plugin not installed; this adds Flutter specific functionality.
    ? Dart plugin not installed; this adds Dart specific functionality.
    ? Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6915495)

[?] Connected device (2 available)
    ? SM M307F (mobile)        ? RZ8MB2YKPDV                              ? android-arm64 ? Android 10 (API 29)
    ? Paresh’s iPhone (mobile) ? 49f62dac6f1da634e5d71981db4d591dc9126e4b ? ios           ? iOS 13.3

! Doctor found issues in 1 category.

This issue does seem to arise when building on a real device and simulator. Tried in iPhone iOS 14.3 and iPhone 8 Simulator and getting this same error, but this does not occur with one device at a time

Anyone find out the resolution for it? It's really annoying to not able to run on multiple ios Simulators.

question from:https://stackoverflow.com/questions/65843967/xcode-build-failed-due-to-concurrent-builds-will-retry-in-2-seconds-in-flutter

Answer 1

This is a relatively common Xcode issue when it's underlying build.db gets locked by some killed xcodebuild process, and it happens in many non-Flutter Xcode projects. And I found some solution to solve this, Here is some approach of them

1. quit XCBuildService from the Mac activity monitor app and try again

2. quit Xcode application or Try closing Xcode/Android Studio/VS Code when building iOS

3. run flutter run -d all --verbose?command directly

4. Try $ flutter clean?

5. Usually deleting DerivedData will fix it.

   ~/Library/Developer/Xcode/DerivedData
   

   DerivedData is where all the intermediate object files, cached modules, code index, logs, etc. lives. If we run each build from a different derived data directory everything will be re-cached on every build, which I expect is a pretty grim performance price.