Code inspection: Function signature cannot contain managed types

This inspection reports calls from Burst-compiled code to methods whose parameter types or return type are managed.

Burst method calls must use Burst-compatible signatures. If a called method accepts object, an interface type, a class, or returns a managed type, this inspection warns on the call site.

Example

In this example, the LogValue method accepts an object parameter. Calling this method inside a Burst-compiled job is not supported and will be flagged.

                using Unity.Burst;
                using Unity.Jobs;

                [BurstCompile]
                public struct ExampleJob : IJob
                {
                    private void LogValue(object value)
                    {
                    }

                    public void Execute()
                    {
                        // Reported: managed parameters are not supported in Burst
                        LogValue(null);
                    }
                }
            

                using Unity.Burst;
                using Unity.Jobs;

                [BurstCompile]
                public struct ExampleJob : IJob
                {
                    private void LogValue(int value)
                    {
                    }

                    public void Execute()
                    {
                        // Correct: Use Burst-compatible value types
                        LogValue(42);
                    }
                }
            

Quick-fix

This inspection does not provide a dedicated quick-fix. Fix it manually by changing the called method signature or by moving the call out of Burst-compiled code.

26 March 2026