Пример #1
0
        protected void GetCompilationReferences(
            TCompilation compilation,
            DiagnosticBag diagnostics,
            out ImmutableArray <MetadataReference> references,
            out IDictionary <ValueTuple <string, string>, MetadataReference> boundReferenceDirectives,
            out ImmutableArray <Location> referenceDirectiveLocations)
        {
            boundReferenceDirectives = null;

            ArrayBuilder <MetadataReference> referencesBuilder = ArrayBuilder <MetadataReference> .GetInstance();

            ArrayBuilder <Location> referenceDirectiveLocationsBuilder = null;

            try
            {
                foreach (var referenceDirective in compilation.ReferenceDirectives)
                {
                    if (compilation.Options.MetadataReferenceResolver == null)
                    {
                        diagnostics.Add(MessageProvider.CreateDiagnostic(MessageProvider.ERR_MetadataReferencesNotSupported, referenceDirective.Location));
                        break;
                    }

                    // we already successfully bound #r with the same value:
                    if (boundReferenceDirectives != null && boundReferenceDirectives.ContainsKey(ValueTuple.Create(referenceDirective.Location.SourceTree.FilePath, referenceDirective.File)))
                    {
                        continue;
                    }

                    MetadataReference boundReference = ResolveReferenceDirective(referenceDirective.File, referenceDirective.Location, compilation);
                    if (boundReference == null)
                    {
                        diagnostics.Add(MessageProvider.CreateDiagnostic(MessageProvider.ERR_MetadataFileNotFound, referenceDirective.Location, referenceDirective.File));
                        continue;
                    }

                    if (boundReferenceDirectives == null)
                    {
                        boundReferenceDirectives           = new Dictionary <ValueTuple <string, string>, MetadataReference>();
                        referenceDirectiveLocationsBuilder = ArrayBuilder <Location> .GetInstance();
                    }

                    referencesBuilder.Add(boundReference);
                    referenceDirectiveLocationsBuilder.Add(referenceDirective.Location);
                    boundReferenceDirectives.Add(ValueTuple.Create(referenceDirective.Location.SourceTree.FilePath, referenceDirective.File), boundReference);
                }

                // add external reference at the end, so that they are processed first:
                referencesBuilder.AddRange(compilation.ExternalReferences);

                // Add all explicit references of the previous script compilation.
                var previousScriptCompilation = compilation.ScriptCompilationInfo?.PreviousScriptCompilation;
                if (previousScriptCompilation != null)
                {
                    referencesBuilder.AddRange(previousScriptCompilation.GetBoundReferenceManager().ExplicitReferences);
                }

                if (boundReferenceDirectives == null)
                {
                    // no directive references resolved successfully:
                    boundReferenceDirectives = SpecializedCollections.EmptyDictionary <ValueTuple <string, string>, MetadataReference>();
                }

                references = referencesBuilder.ToImmutable();
                referenceDirectiveLocations = referenceDirectiveLocationsBuilder?.ToImmutableAndFree() ?? ImmutableArray <Location> .Empty;
            }
            finally
            {
                // Put this in a finally because we have tests that (intentionally) cause ResolveReferenceDirective to throw and
                // we don't want to clutter the test output with leak reports.
                referencesBuilder.Free();
            }
        }
Пример #2
0
        /// <summary>
        /// Resolves given metadata references to assemblies and modules.
        /// </summary>
        /// <param name="compilation">The compilation whose references are being resolved.</param>
        /// <param name="references">List where to store resolved references. References from #r directives will follow references passed to the compilation constructor.</param>
        /// <param name="boundReferenceDirectiveMap">Maps #r values to successfully resolved metadata references. Does not contain values that failed to resolve.</param>
        /// <param name="boundReferenceDirectives">Unique metadata references resolved from #r directives.</param>
        /// <param name="assemblies">List where to store information about resolved assemblies to.</param>
        /// <param name="modules">List where to store information about resolved modules to.</param>
        /// <param name="diagnostics">Diagnostic bag where to report resolution errors.</param>
        /// <returns>
        /// Maps index to <paramref name="references"/> to an index of a resolved assembly or module in <paramref name="assemblies"/> or <paramref name="modules"/>, respectively.
        ///</returns>
        protected ImmutableArray <ResolvedReference> ResolveMetadataReferences(
            TCompilation compilation,
            out ImmutableArray <MetadataReference> references,
            out IDictionary <string, MetadataReference> boundReferenceDirectiveMap,
            out ImmutableArray <MetadataReference> boundReferenceDirectives,
            out ImmutableArray <AssemblyData> assemblies,
            out ImmutableArray <PEModule> modules,
            DiagnosticBag diagnostics)
        {
            // Locations of all #r directives in the order they are listed in the references list.
            ImmutableArray <Location> referenceDirectiveLocations;

            GetCompilationReferences(compilation, diagnostics, out references, out boundReferenceDirectiveMap, out referenceDirectiveLocations);

            // References originating from #r directives precede references supplied as arguments of the compilation.
            int referenceCount          = references.Length;
            int referenceDirectiveCount = (referenceDirectiveLocations != null ? referenceDirectiveLocations.Length : 0);

            var referenceMap = new ResolvedReference[referenceCount];

            // Maps references that were added to the reference set (i.e. not filtered out as duplicates) to a set of names that
            // can be used to alias these references. Duplicate assemblies contribute their aliases into this set.
            Dictionary <MetadataReference, ArrayBuilder <string> > aliasMap = null;

            // Used to filter out duplicate references that reference the same file (resolve to the same full normalized path).
            var boundReferences = new Dictionary <MetadataReference, MetadataReference>(MetadataReferenceEqualityComparer.Instance);

            // Used to filter out assemblies that have the same strong or weak identity.
            // Maps simple name to a list of full names.
            Dictionary <string, List <ReferencedAssemblyIdentity> > assemblyReferencesBySimpleName = null;

            ArrayBuilder <MetadataReference> uniqueDirectiveReferences = (referenceDirectiveLocations != null) ? ArrayBuilder <MetadataReference> .GetInstance() : null;

            ArrayBuilder <AssemblyData> assembliesBuilder = null;
            ArrayBuilder <PEModule>     modulesBuilder    = null;

            // When duplicate references with conflicting EmbedInteropTypes flag are encountered,
            // VB uses the flag from the last one, C# reports an error. We need to enumerate in reverse order
            // so that we find the one that matters first.
            for (int referenceIndex = referenceCount - 1; referenceIndex >= 0; referenceIndex--)
            {
                var boundReference = references[referenceIndex];
                if (boundReference == null)
                {
                    continue;
                }

                // add bound reference if it doesn't exist yet, merging aliases:
                MetadataReference existingReference;
                if (boundReferences.TryGetValue(boundReference, out existingReference))
                {
                    // merge properties of compilation-based references if the underlying compilations are the same
                    if ((object)boundReference != existingReference)
                    {
                        MergeReferenceProperties(existingReference, boundReference, diagnostics, ref aliasMap);
                    }

                    continue;
                }

                boundReferences.Add(boundReference, boundReference);

                Location location;
                if (referenceIndex < referenceDirectiveCount)
                {
                    location = referenceDirectiveLocations[referenceIndex];
                    uniqueDirectiveReferences.Add(boundReference);
                }
                else
                {
                    location = Location.None;
                }

                // compilation reference

                var compilationReference = boundReference as CompilationReference;
                if (compilationReference != null)
                {
                    switch (compilationReference.Properties.Kind)
                    {
                    case MetadataImageKind.Assembly:
                        existingReference = TryAddAssembly(
                            compilationReference.Compilation.Assembly.Identity,
                            boundReference,
                            diagnostics,
                            location,
                            ref assemblyReferencesBySimpleName);

                        if (existingReference != null)
                        {
                            MergeReferenceProperties(existingReference, boundReference, diagnostics, ref aliasMap);
                            continue;
                        }

                        // Note, if SourceAssemblySymbol hasn't been created for
                        // compilationAssembly.Compilation yet, we want this to happen
                        // right now. Conveniently, this constructor will trigger creation of the
                        // SourceAssemblySymbol.
                        var asmData = CreateAssemblyDataForCompilation(compilationReference);
                        AddAssembly(asmData, referenceIndex, referenceMap, ref assembliesBuilder);
                        break;

                    default:
                        throw ExceptionUtilities.UnexpectedValue(compilationReference.Properties.Kind);
                    }

                    continue;
                }

                // PE reference

                var      peReference = (PortableExecutableReference)boundReference;
                Metadata metadata    = GetMetadata(peReference, MessageProvider, location, diagnostics);
                Debug.Assert(metadata != null || diagnostics.HasAnyErrors());

                if (metadata != null)
                {
                    Debug.Assert(metadata != null);

                    switch (peReference.Properties.Kind)
                    {
                    case MetadataImageKind.Assembly:
                        var assemblyMetadata = (AssemblyMetadata)metadata;
                        WeakList <IAssemblySymbol> cachedSymbols = assemblyMetadata.CachedSymbols;

                        if (assemblyMetadata.IsValidAssembly())
                        {
                            PEAssembly assembly = assemblyMetadata.GetAssembly();
                            existingReference = TryAddAssembly(
                                assembly.Identity,
                                peReference,
                                diagnostics,
                                location,
                                ref assemblyReferencesBySimpleName);

                            if (existingReference != null)
                            {
                                MergeReferenceProperties(existingReference, boundReference, diagnostics, ref aliasMap);
                                continue;
                            }

                            var asmData = CreateAssemblyDataForFile(
                                assembly,
                                cachedSymbols,
                                peReference.DocumentationProvider,
                                SimpleAssemblyName,
                                compilation.Options.MetadataImportOptions,
                                peReference.Properties.EmbedInteropTypes);

                            AddAssembly(asmData, referenceIndex, referenceMap, ref assembliesBuilder);
                        }
                        else
                        {
                            diagnostics.Add(MessageProvider.CreateDiagnostic(MessageProvider.ERR_MetadataFileNotAssembly, location, peReference.Display));
                        }

                        // asmData keeps strong ref after this point
                        GC.KeepAlive(assemblyMetadata);
                        break;

                    case MetadataImageKind.Module:
                        var moduleMetadata = (ModuleMetadata)metadata;
                        if (moduleMetadata.Module.IsLinkedModule)
                        {
                            // We don't support netmodules since some checks in the compiler need information from the full PE image
                            // (Machine, Bit32Required, PE image hash).
                            if (!moduleMetadata.Module.IsEntireImageAvailable)
                            {
                                diagnostics.Add(MessageProvider.CreateDiagnostic(MessageProvider.ERR_LinkedNetmoduleMetadataMustProvideFullPEImage, location, peReference.Display));
                            }

                            AddModule(moduleMetadata.Module, referenceIndex, referenceMap, ref modulesBuilder);
                        }
                        else
                        {
                            diagnostics.Add(MessageProvider.CreateDiagnostic(MessageProvider.ERR_MetadataFileNotModule, location, peReference.Display));
                        }
                        break;

                    default:
                        throw ExceptionUtilities.UnexpectedValue(peReference.Properties.Kind);
                    }
                }
            }

            if (uniqueDirectiveReferences != null)
            {
                uniqueDirectiveReferences.ReverseContents();
                boundReferenceDirectives = uniqueDirectiveReferences.ToImmutableAndFree();
            }
            else
            {
                boundReferenceDirectives = ImmutableArray <MetadataReference> .Empty;
            }

            for (int i = 0; i < referenceMap.Length; i++)
            {
                if (!referenceMap[i].IsSkipped)
                {
                    int count = referenceMap[i].Kind == MetadataImageKind.Assembly
                        ? ((object)assembliesBuilder == null ? 0 : assembliesBuilder.Count)
                        : ((object)modulesBuilder == null ? 0 : modulesBuilder.Count);
                    int reversedIndex = count - 1 - referenceMap[i].Index;
                    referenceMap[i] = new ResolvedReference(reversedIndex, referenceMap[i].Kind, GetAliases(references[i], aliasMap));
                }
            }

            if (assembliesBuilder == null)
            {
                assemblies = ImmutableArray <AssemblyData> .Empty;
            }
            else
            {
                assembliesBuilder.ReverseContents();
                assemblies = assembliesBuilder.ToImmutableAndFree();
            }

            if (modulesBuilder == null)
            {
                modules = ImmutableArray <PEModule> .Empty;
            }
            else
            {
                modulesBuilder.ReverseContents();
                modules = modulesBuilder.ToImmutableAndFree();
            }

            return(ImmutableArray.CreateRange(referenceMap));
        }
Пример #3
0
        /// <summary>
        /// Creates a new immutable array based on filtered elements by the predicate. The array must not be null.
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="array">The array to process</param>
        /// <param name="predicate">The delegate that defines the conditions of the element to search for.</param>
        /// <returns></returns>
        public static ImmutableArray <T> WhereAsArray <T>(this ImmutableArray <T> array, Func <T, bool> predicate)
        {
            Debug.Assert(!array.IsDefault);

            ArrayBuilder <T> builder = null;
            bool             none    = true;
            bool             all     = true;

            int n = array.Length;

            for (int i = 0; i < n; i++)
            {
                var a = array[i];
                if (predicate(a))
                {
                    none = false;
                    if (all)
                    {
                        continue;
                    }

                    Debug.Assert(i > 0);
                    if (builder == null)
                    {
                        builder = ArrayBuilder <T> .GetInstance();
                    }

                    builder.Add(a);
                }
                else
                {
                    if (none)
                    {
                        all = false;
                        continue;
                    }

                    Debug.Assert(i > 0);
                    if (all)
                    {
                        Debug.Assert(builder == null);
                        all     = false;
                        builder = ArrayBuilder <T> .GetInstance();

                        for (int j = 0; j < i; j++)
                        {
                            builder.Add(array[j]);
                        }
                    }
                }
            }

            if (builder != null)
            {
                Debug.Assert(!all);
                Debug.Assert(!none);
                return(builder.ToImmutableAndFree());
            }
            else if (all)
            {
                return(array);
            }
            else
            {
                Debug.Assert(none);
                return(ImmutableArray <T> .Empty);
            }
        }
 public static ImmutableArray <T> ToImmutableOrEmptyAndFree <T>(this ArrayBuilder <T>?builder)
 {
     return(builder?.ToImmutableAndFree() ?? ImmutableArray <T> .Empty);
 }
        protected void GetCompilationReferences(
            TCompilation compilation,
            DiagnosticBag diagnostics,
            out ImmutableArray <MetadataReference> references,
            out IDictionary <string, MetadataReference> boundReferenceDirectives,
            out ImmutableArray <Location> referenceDirectiveLocations)
        {
            boundReferenceDirectives = null;

            ArrayBuilder <MetadataReference> referencesBuilder = ArrayBuilder <MetadataReference> .GetInstance();

            ArrayBuilder <Location> referenceDirectiveLocationsBuilder = null;

            try
            {
                foreach (var referenceDirective in compilation.ReferenceDirectives)
                {
                    if (compilation.Options.MetadataReferenceResolver == null || compilation.Options.MetadataReferenceProvider == null)
                    {
                        diagnostics.Add(MessageProvider.CreateDiagnostic(MessageProvider.ERR_MetadataReferencesNotSupported, referenceDirective.Location));
                        break;
                    }

                    // we already successfully bound #r with the same value:
                    if (boundReferenceDirectives != null && boundReferenceDirectives.ContainsKey(referenceDirective.File))
                    {
                        continue;
                    }

                    MetadataReference boundReference = ResolveReferenceDirective(referenceDirective.File, referenceDirective.Location, compilation);
                    if (boundReference == null)
                    {
                        diagnostics.Add(MessageProvider.CreateDiagnostic(MessageProvider.ERR_MetadataFileNotFound, referenceDirective.Location, referenceDirective.File));
                        continue;
                    }

                    if (boundReferenceDirectives == null)
                    {
                        boundReferenceDirectives           = new Dictionary <string, MetadataReference>();
                        referenceDirectiveLocationsBuilder = ArrayBuilder <Location> .GetInstance();
                    }

                    referencesBuilder.Add(boundReference);
                    referenceDirectiveLocationsBuilder.Add(referenceDirective.Location);
                    boundReferenceDirectives.Add(referenceDirective.File, boundReference);
                }

                // Workaround for bug #797360: include facades if we reference a Portable Library:
                referencesBuilder.AddRange(ResolveFacadeReferences(compilation));

                // add external reference at the end, so that they are processed first:
                referencesBuilder.AddRange(compilation.ExternalReferences);

                if (boundReferenceDirectives == null)
                {
                    // no directive references resolved successfully:
                    boundReferenceDirectives = SpecializedCollections.EmptyDictionary <string, MetadataReference>();
                }

                references = referencesBuilder.ToImmutable();
                referenceDirectiveLocations = referenceDirectiveLocationsBuilder == null ? ImmutableArray <Location> .Empty : referenceDirectiveLocationsBuilder.ToImmutableAndFree();
            }
            finally
            {
                // Put this in a finally because we have tests that (intentionally) cause ResolveReferenceDirective to throw and
                // we don't want to clutter the test output with leak reports.
                referencesBuilder.Free();
            }
        }
Пример #6
0
        /// <summary>
        /// Get the import strings for a given method, following forward pointers as necessary.
        /// </summary>
        /// <returns>
        /// For each namespace enclosing the method, a list of import strings, innermost to outermost.
        /// There should always be at least one entry, for the global namespace.
        /// </returns>
        public static ImmutableArray <ImmutableArray <string> > GetCSharpGroupedImportStrings(this ISymUnmanagedReader reader, int methodToken, int methodVersion, out ImmutableArray <string> externAliasStrings)
        {
            externAliasStrings = default(ImmutableArray <string>);

            ImmutableArray <short> groupSizes = default(ImmutableArray <short>);
            bool seenForward = false;

RETRY:
            byte[] bytes = reader.GetCustomDebugInfoBytes(methodToken, methodVersion);
            if (bytes == null)
            {
                return(default(ImmutableArray <ImmutableArray <string> >));
            }

            foreach (var record in GetCustomDebugInfoRecords(bytes))
            {
                switch (record.Kind)
                {
                case CustomDebugInfoKind.UsingInfo:
                    if (!groupSizes.IsDefault)
                    {
                        throw new InvalidOperationException(string.Format("Expected at most one Using record for method {0}", FormatMethodToken(methodToken)));
                    }

                    groupSizes = DecodeUsingRecord(record.Data);
                    break;

                case CustomDebugInfoKind.ForwardInfo:
                    if (!externAliasStrings.IsDefault)
                    {
                        throw new InvalidOperationException(string.Format("Did not expect both Forward and ForwardToModule records for method {0}", FormatMethodToken(methodToken)));
                    }

                    methodToken = DecodeForwardRecord(record.Data);

                    // Follow at most one forward link (as in FUNCBRECEE::ensureNamespaces).
                    // NOTE: Dev11 may produce chains of forward links (e.g. for System.Collections.Immutable).
                    if (!seenForward)
                    {
                        seenForward = true;
                        goto RETRY;
                    }

                    break;

                case CustomDebugInfoKind.ForwardToModuleInfo:
                    if (!externAliasStrings.IsDefault)
                    {
                        throw new InvalidOperationException(string.Format("Expected at most one ForwardToModule record for method {0}", FormatMethodToken(methodToken)));
                    }

                    int moduleInfoMethodToken = DecodeForwardToModuleRecord(record.Data);
                    ImmutableArray <string> allModuleInfoImportStrings = reader.GetMethodByVersion(moduleInfoMethodToken, methodVersion).GetImportStrings();
                    ArrayBuilder <string>   externAliasBuilder         = ArrayBuilder <string> .GetInstance();

                    foreach (string importString in allModuleInfoImportStrings)
                    {
                        if (IsCSharpExternAliasInfo(importString))
                        {
                            externAliasBuilder.Add(importString);
                        }
                    }

                    externAliasStrings = externAliasBuilder.ToImmutableAndFree();
                    break;
                }
            }

            if (groupSizes.IsDefault)
            {
                // This can happen in malformed PDBs (e.g. chains of forwards).
                return(default(ImmutableArray <ImmutableArray <string> >));
            }

            var method = reader.GetMethodByVersion(methodToken, methodVersion);

            if (method == null)
            {
                return(default(ImmutableArray <ImmutableArray <string> >));
            }

            ImmutableArray <string> importStrings = method.GetImportStrings();
            int numImportStrings = importStrings.Length;

            ArrayBuilder <ImmutableArray <string> > resultBuilder = ArrayBuilder <ImmutableArray <string> > .GetInstance(groupSizes.Length);

            ArrayBuilder <string> groupBuilder = ArrayBuilder <string> .GetInstance();

            int pos = 0;

            foreach (short groupSize in groupSizes)
            {
                for (int i = 0; i < groupSize; i++, pos++)
                {
                    if (pos >= numImportStrings)
                    {
                        throw new InvalidOperationException(string.Format("Group size indicates more imports than there are import strings (method {0}).", FormatMethodToken(methodToken)));
                    }

                    string importString = importStrings[pos];
                    if (IsCSharpExternAliasInfo(importString))
                    {
                        throw new InvalidOperationException(string.Format("Encountered extern alias info before all import strings were consumed (method {0}).", FormatMethodToken(methodToken)));
                    }

                    groupBuilder.Add(importString);
                }

                resultBuilder.Add(groupBuilder.ToImmutable());
                groupBuilder.Clear();
            }

            if (externAliasStrings.IsDefault)
            {
                Debug.Assert(groupBuilder.Count == 0);

                // Extern alias detail strings (prefix "Z") are not included in the group counts.
                for (; pos < numImportStrings; pos++)
                {
                    string importString = importStrings[pos];
                    if (!IsCSharpExternAliasInfo(importString))
                    {
                        throw new InvalidOperationException(string.Format("Expected only extern alias info strings after consuming the indicated number of imports (method {0}).", FormatMethodToken(methodToken)));
                    }

                    groupBuilder.Add(importString);
                }

                externAliasStrings = groupBuilder.ToImmutableAndFree();
            }
            else
            {
                groupBuilder.Free();

                if (pos < numImportStrings)
                {
                    throw new InvalidOperationException(string.Format("Group size indicates fewer imports than there are import strings (method {0}).", FormatMethodToken(methodToken)));
                }
            }

            return(resultBuilder.ToImmutableAndFree());
        }
 internal ImmutableArray <GeneratedSourceText> ToImmutableAndFree() => _sourcesAdded.ToImmutableAndFree();
Пример #8
0
        // Expects correct arguments.
        internal CompilationOptions(
            OutputKind outputKind,
            bool reportSuppressedDiagnostics,
            string moduleName,
            string mainTypeName,
            string scriptClassName,
            string cryptoKeyContainer,
            string cryptoKeyFile,
            ImmutableArray <byte> cryptoPublicKey,
            bool?delaySign,
            bool publicSign,
            OptimizationLevel optimizationLevel,
            bool checkOverflow,
            Platform platform,
            ReportDiagnostic generalDiagnosticOption,
            int warningLevel,
            ImmutableDictionary <string, ReportDiagnostic> specificDiagnosticOptions,
            bool concurrentBuild,
            bool deterministic,
            DateTime currentLocalTime,
            bool debugPlusMode,
            XmlReferenceResolver xmlReferenceResolver,
            SourceReferenceResolver sourceReferenceResolver,
            MetadataReferenceResolver metadataReferenceResolver,
            AssemblyIdentityComparer assemblyIdentityComparer,
            StrongNameProvider strongNameProvider,
            MetadataImportOptions metadataImportOptions,
            bool referencesSupersedeLowerVersions)
        {
            this.OutputKind                       = outputKind;
            this.ModuleName                       = moduleName;
            this.MainTypeName                     = mainTypeName;
            this.ScriptClassName                  = scriptClassName ?? WellKnownMemberNames.DefaultScriptClassName;
            this.CryptoKeyContainer               = cryptoKeyContainer;
            this.CryptoKeyFile                    = cryptoKeyFile;
            this.CryptoPublicKey                  = cryptoPublicKey.NullToEmpty();
            this.DelaySign                        = delaySign;
            this.CheckOverflow                    = checkOverflow;
            this.Platform                         = platform;
            this.GeneralDiagnosticOption          = generalDiagnosticOption;
            this.WarningLevel                     = warningLevel;
            this.SpecificDiagnosticOptions        = specificDiagnosticOptions;
            this.ReportSuppressedDiagnostics      = reportSuppressedDiagnostics;
            this.OptimizationLevel                = optimizationLevel;
            this.ConcurrentBuild                  = concurrentBuild;
            this.Deterministic                    = deterministic;
            this.CurrentLocalTime                 = currentLocalTime;
            this.DebugPlusMode                    = debugPlusMode;
            this.XmlReferenceResolver             = xmlReferenceResolver;
            this.SourceReferenceResolver          = sourceReferenceResolver;
            this.MetadataReferenceResolver        = metadataReferenceResolver;
            this.StrongNameProvider               = strongNameProvider;
            this.AssemblyIdentityComparer         = assemblyIdentityComparer ?? AssemblyIdentityComparer.Default;
            this.MetadataImportOptions            = metadataImportOptions;
            this.ReferencesSupersedeLowerVersions = referencesSupersedeLowerVersions;
            this.PublicSign                       = publicSign;

            _lazyErrors = new Lazy <ImmutableArray <Diagnostic> >(() =>
            {
                ArrayBuilder <Diagnostic> builder = ArrayBuilder <Diagnostic> .GetInstance();
                ValidateOptions(builder);
                return(builder.ToImmutableAndFree());
            });
        }