what is the problem ?

[moham2edatef]

[+15769 ms] [+15774 ms] Persisting file store
[ +99 ms] [ +55 ms] Done persisting file store
[ +1 ms] [ +5 ms] Target kernel_snapshot failed: Exception
[ +1 ms] #0 KernelSnapshot.build (package:flutter_tools/src/build_system/targets/common.dart:241:7)
[ +1 ms]
[ +1 ms] #1 _BuildInstance._invokeInternal (package:flutter_tools/src/build_system/build_system.dart:839:9)
[ +1 ms]
[ +1 ms] #2 Future.wait. (dart:async/future.dart:521:21)
[ +1 ms]
[ +1 ms] #3 _BuildInstance.invokeTarget (package:flutter_tools/src/build_system/build_system.dart:777:32)
[ +1 ms]
[ +1 ms] #4 FlutterBuildSystem.build (package:flutter_tools/src/build_system/build_system.dart:606:16)
[ +1 ms]
[ +1 ms] #5 AssembleCommand.runCommand (package:flutter_tools/src/commands/assemble.dart:320:32)
[ +1 ms]
[ +1 ms] #6 FlutterCommand.run. (package:flutter_tools/src/runner/flutter_command.dart:1183:27)
[ +1 ms]
[ +2 ms] #7 AppContext.run. (package:flutter_tools/src/base/context.dart:150:19)
[ +3 ms]
[ +1 ms] #8 CommandRunner.runCommand (package:args/command_runner.dart:209:13)
[ +1 ms]
[ +1 ms] #9 FlutterCommandRunner.runCommand. (package:flutter_tools/src/runner/flutter_command_runner.dart:281:9)
[ +1 ms]
[ +1 ms] #10 AppContext.run. (package:flutter_tools/src/base/context.dart:150:19)
[ +1 ms]
[ +1 ms] #11 FlutterCommandRunner.runCommand (package:flutter_tools/src/runner/flutter_command_runner.dart:229:5)
[ +1 ms]
[ +1 ms] #12 run.. (package:flutter_tools/runner.dart:62:9)
[ +1 ms]
[ +1 ms] #13 AppContext.run. (package:flutter_tools/src/base/context.dart:150:19)
[ +2 ms]
[ +2 ms] #14 main (package:flutter_tools/executable.dart:94:3)
[ +1 ms]
[ +1 ms] [ +16 ms]
[ +1 ms] #0 throwToolExit (package:flutter_tools/src/base/common.dart:10:3)
[ +1 ms] #1 AssembleCommand.runCommand (package:flutter_tools/src/commands/assemble.dart:337:7)
[ +1 ms]
[ +1 ms] #2 FlutterCommand.run. (package:flutter_tools/src/runner/flutter_command.dart:1183:27)
[ +1 ms]
[ +1 ms] #3 AppContext.run. (package:flutter_tools/src/base/context.dart:150:19)
[ +1 ms]
[ +1 ms] #4 CommandRunner.runCommand (package:args/command_runner.dart:209:13)
[ +1 ms]
[ +3 ms] #5 FlutterCommandRunner.runCommand. (package:flutter_tools/src/runner/flutter_command_runner.dart:281:9)
[ +2 ms]
[ +1 ms] #6 AppContext.run. (package:flutter_tools/src/base/context.dart:150:19)
[ +1 ms]
[ +2 ms] [ +28 ms] "flutter assemble" took 50,515ms.
[ +2 ms] #7 FlutterCommandRunner.runCommand (package:flutter_tools/src/runner/flutter_command_runner.dart:229:5)
[ +2 ms]
[ +2 ms] #8 run.. (package:flutter_tools/runner.dart:62:9)
[ +1 ms]
[ +1 ms] #9 AppContext.run. (package:flutter_tools/src/base/context.dart:150:19)
[ +1 ms]
[ +1 ms] #10 main (package:flutter_tools/executable.dart:94:3)
[ +1 ms]
[ +211 ms] [ +256 ms] ensureAnalyticsSent: 253ms
[ +1 ms] [ +2 ms] Running shutdown hooks
[ +1 ms] [ ] Shutdown hooks complete
[ +1 ms] [ ] exiting with code 1
[ +94 ms] > Task :app:compileFlutterBuildDebug FAILED
[ +200 ms] FAILURE: Build failed with an exception.
[ +3 ms] * Where:
[ +1 ms] Script 'D:\flutter\packages\flutter_tools\gradle\flutter.gradle' line: 1156
[ +2 ms] * What went wrong:
[ +2 ms] Execution failed for task ':app:compileFlutterBuildDebug'.
[ +2 ms] > Process 'command 'D:\flutter\bin\flutter.bat'' finished with non-zero exit value 1
[ +3 ms] * Try:
[ +2 ms] Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
[ +3 ms] * Get more help at https://help.gradle.org
[ +2 ms] BUILD FAILED in 1m 1s
[ +6 ms] Deprecated Gradle features were used in this build, making it incompatible with Gradle 7.0.
[ +2 ms] Use '--warning-mode all' to show the individual deprecation warnings.
[ +2 ms] See https://docs.gradle.org/6.7/userguide/command_line_interface.html#sec:command_line_warnings
[ +4 ms] 1 actionable task: 1 executed
[ +538 ms] Running Gradle task 'assembleDebug'... (completed in 63.2s)
[ +8 ms] Exception: Gradle task assembleDebug failed with exit code 1
[ +4 ms] "flutter run" took 67,295ms.
[ +16 ms]
#0 throwToolExit (package:flutter_tools/src/base/common.dart:10:3)
#1 RunCommand.runCommand (package:flutter_tools/src/commands/run.dart:699:9)

#2 FlutterCommand.run. (package:flutter_tools/src/runner/flutter_command.dart:1183:27)

#3 AppContext.run. (package:flutter_tools/src/base/context.dart:150:19)

#4 CommandRunner.runCommand (package:args/command_runner.dart:209:13)

#5 FlutterCommandRunner.runCommand. (package:flutter_tools/src/runner/flutter_command_runner.dart:281:9)

#6 AppContext.run. (package:flutter_tools/src/base/context.dart:150:19)

#7 FlutterCommandRunner.runCommand (package:flutter_tools/src/runner/flutter_command_runner.dart:229:5)

#8 run.. (package:flutter_tools/runner.dart:62:9)

#9 AppContext.run. (package:flutter_tools/src/base/context.dart:150:19)

#10 main (package:flutter_tools/executable.dart:94:3)