Code inspection: Debug logging functions only accept strings

This inspection reports calls to Debug.Log, Debug.LogWarning, or Debug.LogError in code compiled by the Burst compiler when the logged value is not a string.

Burst debug logging only accepts regular strings and supported fixed strings. Logging numbers, structs, or other non-string values directly will trigger this inspection because it would involve implicit conversion or boxing to a managed object.

Example

In this example, an integer is passed directly to Debug.Log. This is not supported in Burst-compiled code.

                using Unity.Burst;
                using Unity.Jobs;
                using UnityEngine;

                [BurstCompile]
                public struct ExampleJob : IJob
                {
                    public void Execute()
                    {
                        // Reported: Debug.Log argument must be a string or fixed string
                        Debug.Log(42);
                    }
                }
            

                using Unity.Burst;
                using Unity.Collections;
                using Unity.Jobs;
                using UnityEngine;

                [BurstCompile]
                public struct ExampleJob : IJob
                {
                    public void Execute()
                    {
                        // Pass a string or a Burst-compatible fixed string
                        FixedString128Bytes message = "Value: 42";
                        Debug.Log(message);
                    }
                }
            

Quick-fix

This inspection does not provide a dedicated quick-fix. Fix it manually by changing the logged argument to a string or a fixed string.

26 March 2026