Failed to build iOS app after upgrading my flutter version

Question

I am new to flutter iOS development I have upgraded my flutter version and then after my application cannot build iOS app I am getting this exception which I mentioned below, please help me out. Before that it worked properly should I reinstall flutter or any other ideas means a lot, Thanks in advance

Xcode build done.                                           10.7s
Failed to build iOS app
Error output from Xcode build:
↳
    ** BUILD FAILED **
Xcode's output:
↳
    === BUILD TARGET map_view OF PROJECT Pods WITH CONFIGURATION Debug ===
    /Users/harshavardhan/Workspace/fleetconnect_flutter/ios/Pods/FMDB/src/fmdb/FMDatabase.m:1486:15: warning: 'sqlite3_wal_checkpoint_v2' is only available on iOS 5.0 or newer [-Wunguarded-availability]
        int err = sqlite3_wal_checkpoint_v2(_db, dbName, checkpointMode, logFrameCount, checkpointCount);
                  ^~~~~~~~~~~~~~~~~~~~~~~~~
    In module 'SQLite3' imported from /Users/harshavardhan/Workspace/fleetconnect_flutter/ios/Pods/FMDB/src/fmdb/FMDatabase.m:8:
    /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator12.1.sdk/usr/include/sqlite3.h:8244:16: note: 'sqlite3_wal_checkpoint_v2' has been explicitly marked partial here
    SQLITE_API int sqlite3_wal_checkpoint_v2(
                   ^
    /Users/harshavardhan/Workspace/fleetconnect_flutter/ios/Pods/FMDB/src/fmdb/FMDatabase.m:1486:15: note: enclose 'sqlite3_wal_checkpoint_v2' in an @available check to silence this warning
        int err = sqlite3_wal_checkpoint_v2(_db, dbName, checkpointMode, logFrameCount, checkpointCount);
                  ^~~~~~~~~~~~~~~~~~~~~~~~~
    1 warning generated.
    === BUILD TARGET map_view OF PROJECT Pods WITH CONFIGURATION Debug ===
    /Users/harshavardhan/Workspace/fleetconnect_flutter/ios/Pods/FMDB/src/fmdb/FMDatabaseQueue.m:101:9: warning: 'dispatch_queue_set_specific' is only available on iOS 5.0 or newer [-Wunguarded-availability]
            dispatch_queue_set_specific(_queue, kDispatchQueueSpecificKey, (__bridge void *)self, NULL);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~
    In module 'Foundation' imported from /Users/harshavardhan/Workspace/fleetconnect_flutter/ios/Pods/FMDB/src/fmdb/FMDatabaseQueue.h:9:
    In module 'CoreFoundation' imported from /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator12.1.sdk/System/Library/Frameworks/Foundation.framework/Headers/Foundation.h:6:
    In module 'Dispatch' imported from /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator12.1.sdk/System/Library/Frameworks/CoreFoundation.framework/Headers/CFStream.h:20:
    /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator12.1.sdk/usr/include/dispatch/queue.h:1352:1: note: 'dispatch_queue_set_specific' has been explicitly marked partial here
    dispatch_queue_set_specific(dispatch_queue_t queue, const void *key,
    ^
    /Users/harshavardhan/Workspace/fleetconnect_flutter/ios/Pods/FMDB/src/fmdb/FMDatabaseQueue.m:101:9: note: enclose 'dispatch_queue_set_specific' in an @available check to silence this warning
            dispatch_queue_set_specific(_queue, kDispatchQueueSpecificKey, (__bridge void *)self, NULL);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~
    /Users/harshavardhan/Workspace/fleetconnect_flutter/ios/Pods/FMDB/src/fmdb/FMDatabaseQueue.m:184:54: warning: 'dispatch_get_specific' is only available on iOS 5.0 or newer [-Wunguarded-availability]
        FMDatabaseQueue *currentSyncQueue = (__bridge id)dispatch_get_specific(kDispatchQueueSpecificKey);
                                                         ^~~~~~~~~~~~~~~~~~~~~
    In module 'Foundation' imported from /Users/harshavardhan/Workspace/fleetconnect_flutter/ios/Pods/FMDB/src/fmdb/FMDatabaseQueue.h:9:
    In module 'CoreFoundation' imported from /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator12.1.sdk/System/Library/Frameworks/Foundation.framework/Headers/Foundation.h:6:
    In module 'Dispatch' imported from /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator12.1.sdk/System/Library/Frameworks/CoreFoundation.framework/Headers/CFStream.h:20:
    /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator12.1.sdk/usr/include/dispatch/queue.h:1408:1: note: 'dispatch_get_specific' has been explicitly marked partial here
    dispatch_get_specific(const void *key);
    ^
    /Users/harshavardhan/Workspace/fleetconnect_flutter/ios/Pods/FMDB/src/fmdb/FMDatabaseQueue.m:184:54: note: enclose 'dispatch_get_specific' in an @available check to silence this warning
        FMDatabaseQueue *currentSyncQueue = (__bridge id)dispatch_get_specific(kDispatchQueueSpecificKey);
                                                         ^~~~~~~~~~~~~~~~~~~~~
    2 warnings generated.
    /Users/harshavardhan/development/flutter/.pub-cache/hosted/pub.dartlang.org/fluttertoast-2.2.11/ios/Classes/FluttertoastPlugin.m:19:23: warning: unused variable 'viewController' [-Wunused-variable]
        UIViewController *viewController =
                          ^
    /Users/harshavardhan/development/flutter/.pub-cache/hosted/pub.dartlang.org/fluttertoast-2.2.11/ios/Classes/FluttertoastPlugin.m:48:19: warning: unused variable 'size' [-Wunused-variable]
            NSNumber *size = call.arguments[@"size"];
                      ^
    2 warnings generated.
    === BUILD TARGET Runner OF PROJECT Runner WITH CONFIGURATION Debug ===
    ld: framework not found Flutter
    clang: error: linker command failed with exit code 1 (use -v to see invocation)
Could not build the application for the simulator.
Error launching application on iPhone XR.
Exited (sigterm)

Answer 1

Try to clean the project (Flutter clean) in the terminal, run pod install from the ios directory and then run the application again.

If that does not seem to fix the problem, others have had their luck with this issue by reinstalling Flutter as you yourself proposed.