stride3d/stride · error · InvalidOperationException

Couldn't find method 'PreloadLibrary' in

Error message

Couldn't find method 'PreloadLibrary' in {nativeLibraryHelperType}

What it means

LoadNativeDependencies reflects for a 'PreloadLibrary' method on Stride.Core.NativeLibraryHelper and throws an InvalidOperationException if GetMethod returns null. The preloading contract (method invoked as PreloadLibrary(libName, null)) is not present on the restored Stride.Core assembly.

Solutions

Pin/restore the Stride runtime version the resolver was built against.
Verify the method on the actual DLL: typeof(NativeLibraryHelper).GetMethod("PreloadLibrary", BindingFlags.Public|BindingFlags.NonPublic|BindingFlags.Static).
Update the resolver to call the new preload API if you upgraded Stride intentionally.
Disable aggressive trimming/publish trimming for the assemblies being reflected over.

Example fix

// before
publishOptions.TrimMode = "full"; // trims PreloadLibrary away from Stride.Core
// after
publishOptions.TrimMode = "partial"; // or exclude Stride.Core from trimming

Defensive patterns

Strategy: try-catch

Validate before calling

var t = Assembly.LoadFrom(strideCorePath).GetType("Stride.Core.NativeLibraryHelper");
if (t?.GetMethod("PreloadLibrary") == null)
    throw new InvalidOperationException("Stride.Core build has no accessible PreloadLibrary — resolver/runtime mismatch or trimming removed it.");

Type guard

static bool HasPreloadLibrary(Assembly strideCore) =>
    strideCore.GetType("Stride.Core.NativeLibraryHelper")
        ?.GetMethod("PreloadLibrary") != null;

Try / catch

try
{
    resolver.SetupNuGet(packageName, packageVersion, targetFramework);
}
catch (InvalidOperationException ex) when (ex.Message.Contains("Couldn't find method 'PreloadLibrary'"))
{
    logger.Error("PreloadLibrary missing on Stride.Core.NativeLibraryHelper; check version alignment and trimming settings.");
    throw;
}

Prevention

Exclude Stride.Core from publish trimming (TrimMode=partial or TrimmerRootAssembly).
Pin Stride runtime versions to those the resolver's reflection contract targets.
Run SetupNuGet as part of CI so API drift is caught before release.

When it happens

Trigger: nativeLibraryHelperType was found but has no 'PreloadLibrary' method with a bindable signature (renamed, internal, or parameter changes) in the restored Stride.Core version.

Common situations: Stride runtime upgraded ahead of the NuGetResolver reflection contract; custom Stride.Core forks without PreloadLibrary; strict trimming removing the method.

Related errors

AI-assisted analysis of stride3d/stride@96fad776d2 (2026-09-14). Data as JSON: /api/errors/384daf6f909f872a. Report an issue: GitHub.

Appendix: source

Thrown at sources/shared/Stride.NuGetResolver/NuGetAssemblyResolver.cs:289

        var nativeLibraryHelperType = strideCoreAssembly.GetType("Stride.Core.NativeLibraryHelper")
            ?? throw new InvalidOperationException($"Couldn't find type 'Stride.Core.NativeLibraryHelper' in {strideCoreAssembly}");
        var registerDependencyMethod = nativeLibraryHelperType.GetMethod("RegisterDependency")
            ?? throw new InvalidOperationException($"Couldn't find method 'RegisterDependency' in {nativeLibraryHelperType}");
        foreach (var lib in nativeLibs)
            registerDependencyMethod.Invoke(null, [lib]);
    }

    /// <summary>
    /// Loads the listed native libs in Stride.Core.NativeLibraryHelper using reflection to avoid a compile time dependency on Stride.Core
    /// </summary>
    private static void LoadNativeDependencies(Dictionary<string, string> assemblyNameToPath, List<string> nativeLibs)
    {
        var strideCoreAssembly = Assembly.LoadFrom(assemblyNameToPath["Stride.Core"])
            ?? throw new InvalidOperationException("Couldn't find assembly 'Stride.Core' in restored packages");
        var nativeLibraryHelperType = strideCoreAssembly.GetType("Stride.Core.NativeLibraryHelper")
            ?? throw new InvalidOperationException($"Couldn't find type 'Stride.Core.NativeLibraryHelper' in {strideCoreAssembly}");
        var preloadLibraryMethod = nativeLibraryHelperType.GetMethod("PreloadLibrary")
            ?? throw new InvalidOperationException($"Couldn't find method 'PreloadLibrary' in {nativeLibraryHelperType}");
        foreach (var lib in nativeLibs)
        {
            var libName = Path.GetFileNameWithoutExtension(lib);
            preloadLibraryMethod.Invoke(null, [libName, null]);
        }
    }

    public class Logger : ILogger
    {
        private readonly object logLock = new();
        private Action<LogLevel, string>? action;
        public List<(LogLevel Level, string Message)> Logs { get; } = [];

        public void SetupLogAction(Action<LogLevel, string> action)
        {
            lock (logLock)
            {
                this.action = action;

View on GitHub (pinned to 96fad776d2)