Generate a unique ID at compile time to work around a CLR bug

.gitignore

@@ -35,5 +35,7 @@ _ReSharper*/
 *.userprefs
 *.swp
 *.DotSettings
+#Ignore custom generated files
+LibGit2Sharp/Core/UniqueIdentifier.cs
 
 !Lib/NativeBinaries/*/*.pdb

CustomBuildTasks/CustomBuildTasks.csproj

@@ -0,0 +1,42 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
+  <PropertyGroup>
+    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
+    <ProjectGuid>{B6138573-A4B9-44E7-83C2-8964CAF51EDA}</ProjectGuid>
+    <OutputType>Library</OutputType>
+    <AppDesignerFolder>Properties</AppDesignerFolder>
+    <RootNamespace>CustomBuildTasks</RootNamespace>
+    <AssemblyName>CustomBuildTasks</AssemblyName>
+    <TargetFrameworkVersion>v3.5</TargetFrameworkVersion>
+    <FileAlignment>512</FileAlignment>
+    <TargetFrameworkProfile />
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>full</DebugType>
+    <Optimize>false</Optimize>
+    <OutputPath>bin\Debug\</OutputPath>
+    <DefineConstants>DEBUG;TRACE</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <OutputPath>bin\Release\</OutputPath>
+    <DefineConstants>TRACE</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+  </PropertyGroup>
+  <ItemGroup>
+    <Reference Include="System" />
+    <Reference Include="Microsoft.Build.Framework" />
+    <Reference Include="Microsoft.Build.Utilities" />
+  </ItemGroup>
+  <ItemGroup>
+    <Compile Include="GenerateUniqueIdentifierTask.cs" />
+  </ItemGroup>
+  <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
+</Project>

CustomBuildTasks/GenerateUniqueIdentifierTask.cs

@@ -0,0 +1,36 @@
+using System;
+using System.IO;
+using System.Text;
+using Microsoft.Build.Framework;
+using Microsoft.Build.Utilities;
+
+namespace CustomBuildTasks
+{
+    public class GenerateUniqueIdentifierTask : Task
+    {
+        public override bool Execute()
+        {
+            using (FileStream fs = new FileStream(this.OutputFile, FileMode.Create, FileAccess.Write, FileShare.None))
+            using (StreamWriter sw = new StreamWriter(fs, Encoding.UTF8))
+            {
+                sw.WriteLine("using System;");
+                sw.WriteLine();
+                sw.WriteLine("namespace LibGit2Sharp.Core");
+                sw.WriteLine("{");
+                sw.WriteLine("  internal static class UniqueId");
+                sw.WriteLine("  {");
+                sw.WriteLine("    public const String UniqueIdentifier = \"" + Guid.NewGuid().ToString() + "\";");
+                sw.WriteLine("  }");
+                sw.WriteLine("}");
+            }
+
+            return true;
+        }
+
+        public String OutputFile
+        {
+            get;
+            set;
+        }
+    }
+}

LibGit2Sharp/Core/FilePathMarshaler.cs

@@ -11,6 +11,7 @@ namespace LibGit2Sharp.Core
     ///
     ///   Use this marshaler for return values, for example:
     ///   [return: MarshalAs(UnmanagedType.CustomMarshaler,
+    ///                      MarshalCookie = UniqueId.UniqueIdentifier,
     ///                      MarshalTypeRef = typeof(FilePathNoCleanupMarshaler))]
     /// </summary>
     internal class FilePathNoCleanupMarshaler : FilePathMarshaler
@@ -42,6 +43,7 @@ public override void CleanUpNativeData(IntPtr pNativeData)
     ///   [DllImport(libgit2)]
     ///   internal static extern int git_index_open(out IndexSafeHandle index,
     ///       [MarshalAs(UnmanagedType.CustomMarshaler,
+    ///                  MarshalCookie = UniqueId.UniqueIdentifier,
     ///                  MarshalTypeRef = typeof(FilePathMarshaler))] FilePath indexpath);
     /// </summary>
     internal class FilePathMarshaler : ICustomMarshaler

LibGit2Sharp/Core/Utf8Marshaler.cs

@@ -11,6 +11,7 @@ namespace LibGit2Sharp.Core
     ///
     ///   Use this marshaler for return values, for example:
     ///   [return: MarshalAs(UnmanagedType.CustomMarshaler,
+    ///                      MarshalCookie = UniqueId.UniqueIdentifier,
     ///                      MarshalTypeRef = typeof(Utf8NoCleanupMarshaler))]
     /// </summary>
     internal class Utf8NoCleanupMarshaler : Utf8Marshaler
@@ -42,6 +43,7 @@ public override void CleanUpNativeData(IntPtr pNativeData)
     ///   [DllImport(libgit2)]
     ///   internal static extern int git_tag_delete(RepositorySafeHandle repo,
     ///       [MarshalAs(UnmanagedType.CustomMarshaler,
+    ///                  MarshalCookie = UniqueId.UniqueIdentifier,
     ///                  MarshalTypeRef = typeof(Utf8Marshaler))] String tagName);
     /// </summary>
     internal class Utf8Marshaler : ICustomMarshaler

LibGit2Sharp/LibGit2Sharp.csproj

@@ -250,6 +250,7 @@
     <Compile Include="TreeEntryDefinition.cs" />
     <Compile Include="VoidReference.cs" />
     <Compile Include="Core\RawContentStream.cs" />
+    <Compile Include="Core\UniqueIdentifier.cs" />
   </ItemGroup>
   <ItemGroup>
     <CodeAnalysisDictionary Include="CustomDictionary.xml" />
@@ -261,6 +262,7 @@
     <EmbeddedResource Include="libgit2sharp_hash.txt" />
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
+  <Import Project="UniqueIdentifier.targets" />
   <PropertyGroup>
     <PreBuildEvent>
     </PreBuildEvent>

LibGit2Sharp/UniqueIdentifier.targets

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+
+  <!-- Import the version of CustomBuildTasks.dll that is dropped in the repository. -->
+  <UsingTask TaskName="GenerateUniqueIdentifierTask" AssemblyFile="..\Lib\CustomBuildTasks\CustomBuildTasks.dll" />
+
+  <!-- Set the path of the generated UniqueIdentifier.cs file. -->
+  <PropertyGroup>
+    <UniqueIdentifierPath>Core\UniqueIdentifier.cs</UniqueIdentifierPath>
+    <CoreCompileDependsOn>$(CoreCompileDependsOn);GenerateUniqueIdentifierCs</CoreCompileDependsOn>
+    <CoreCleanDependsOn>$(CoreCleanDependsOn);CleanUniqueIdentifierCs</CoreCleanDependsOn>
+  </PropertyGroup>
+
+  <!-- This target runs if any of the projects or .cs files for the project have changed since the last time
+      the UniqueIdentifier.cs file was generated. -->
+  <Target Name="GenerateUniqueIdentifierCs"
+          Inputs="$(MSBuildThisFileFullPath);$(MSBuildAllProjects);@(Compile)"
+          Outputs="$(UniqueIdentifierPath)">
+    <GenerateUniqueIdentifierTask OutputFile="$(UniqueIdentifierPath)" />
+  </Target>
+
+  <Target Name="CleanUniqueIdentifierCs">
+    <Delete Files="$(UniqueIdentifierPath)" />
+  </Target>
+
+</Project>