dotnet/BenchmarkDotNet · error · ArgumentOutOfRangeException

Runtime Moniker not supported

Error message

Runtime Moniker not supported

What it means

RuntimeMonikerExtensions.GetRuntime maps each RuntimeMoniker enum value to a runtime instance via a switch; the default arm throws ArgumentOutOfRangeException ("Runtime Moniker not supported"). This fires when a moniker value has no mapping, typically a newly added enum member the loaded library version does not recognize.

Source

Thrown at src/BenchmarkDotNet/Extensions/RuntimeMonikerExtensions.cs:83

                    return MonoRuntime.Mono70;
                case RuntimeMoniker.Mono80:
                    return MonoRuntime.Mono80;
                case RuntimeMoniker.Mono90:
                    return MonoRuntime.Mono90;
                case RuntimeMoniker.Mono10_0:
                    return MonoRuntime.Mono10_0;
                case RuntimeMoniker.Mono11_0:
                    return MonoRuntime.Mono11_0;
                case RuntimeMoniker.R2R80:
                    return R2RRuntime.Net80;
                case RuntimeMoniker.R2R90:
                    return R2RRuntime.Net90;
                case RuntimeMoniker.R2R10_0:
                    return R2RRuntime.Net10_0;
                case RuntimeMoniker.R2R11_0:
                    return R2RRuntime.Net11_0;
                default:
                    throw new ArgumentOutOfRangeException(nameof(runtimeMoniker), runtimeMoniker, "Runtime Moniker not supported");
            }
        }

        internal static Version GetRuntimeVersion(this RuntimeMoniker runtimeMoniker) => runtimeMoniker switch
        {
            RuntimeMoniker.Net461 => new Version(4, 6, 1),
            RuntimeMoniker.Net462 => new Version(4, 6, 2),
            RuntimeMoniker.Net47 => new Version(4, 7),
            RuntimeMoniker.Net471 => new Version(4, 7, 1),
            RuntimeMoniker.Net472 => new Version(4, 7, 2),
            RuntimeMoniker.Net48 => new Version(4, 8),
            RuntimeMoniker.Net481 => new Version(4, 8, 1),
            RuntimeMoniker.NetCoreApp20 => new Version(2, 0),
            RuntimeMoniker.NetCoreApp21 => new Version(2, 1),
            RuntimeMoniker.NetCoreApp22 => new Version(2, 2),
            RuntimeMoniker.NetCoreApp30 => new Version(3, 0),
            RuntimeMoniker.NetCoreApp31 => new Version(3, 1),
            RuntimeMoniker.Net50 => new Version(5, 0),

View on GitHub (pinned to b515068b61)

Solutions

1. Upgrade BenchmarkDotNet to a version that supports the RuntimeMoniker you are using.
2. Use a moniker known to be supported by your installed version (e.g. Net90 instead of a newer one).
3. Verify the enum value is within the supported set before configuring the job.

Example fix

// before (on an older BenchmarkDotNet build)
job = Job.Default.WithRuntime(CoreRuntime.Net100); // moniker unsupported

// after
job = Job.Default.WithRuntime(CoreRuntime.Net90);

if (!Enum.IsDefined(typeof(RuntimeMoniker), moniker)) throw new ArgumentOutOfRangeException(nameof(moniker));
// and pin a BenchmarkDotNet version that maps the moniker you use

When it happens

Trigger: Passing a RuntimeMoniker value not covered by the GetRuntime switch (e.g. a moniker introduced in a newer BenchmarkDotNet release while an older version is loaded, or a future/undefined enum value).

Common situations: Version mismatch between the RuntimeMoniker enum the code was compiled against and the installed BenchmarkDotNet, using a preview moniker in a stable build, or casting an invalid integer to RuntimeMoniker.

Related errors

• String cannot be empty.
• GetRuntimeVersion not implemented for {runtimeMoniker}
• Please use job.Env.Jit to specify Jit in explicit way
• Property name must be non-empty.
• Runtime moniker {runtimeMoniker} is not supported

AI-assisted analysis of dotnet/BenchmarkDotNet@b515068b61 (2026-08-13). Data as JSON: /api/errors/5a38c6ece1127bf8. Report an issue: GitHub.