[automated] Merge branch 'release/8.0' => 'release/8.0-staging'

NuGet.config

@@ -9,7 +9,7 @@
     <clear />
     <!--Begin: Package sources managed by Dependency Flow automation. Do not edit the sources below.-->
     <!--  Begin: Package sources from dotnet-emsdk -->
-    <add key="darc-pub-dotnet-emsdk-35ebe6f" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/darc-pub-dotnet-emsdk-35ebe6f3/nuget/v3/index.json" />
+    <add key="darc-pub-dotnet-emsdk-ac9f809" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/darc-pub-dotnet-emsdk-ac9f8092/nuget/v3/index.json" />
     <!--  End: Package sources from dotnet-emsdk -->
     <!--  Begin: Package sources from dotnet-sdk -->
     <!--  End: Package sources from dotnet-sdk -->

eng/Version.Details.xml

@@ -86,18 +86,18 @@
       <Sha>02fe27cd6a9b001c8feb7938e6ef4b3799745759</Sha>
       <SourceBuild RepoName="command-line-api" ManagedOnly="true" />
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.Cecil" Version="0.11.4-alpha.26158.1">
+    <Dependency Name="Microsoft.DotNet.Cecil" Version="0.11.4-alpha.26281.3">
       <Uri>https://github.com/dotnet/cecil</Uri>
-      <Sha>dc12f3e6ccb3fd7b76c0d5ee3365e6b58d796de0</Sha>
+      <Sha>fca1a685c57d208f52fd7e7ba48e2059e3bf0c34</Sha>
       <SourceBuild RepoName="cecil" ManagedOnly="true" />
     </Dependency>
-    <Dependency Name="Microsoft.NET.Workload.Emscripten.Current.Manifest-8.0.100" Version="8.0.28">
+    <Dependency Name="Microsoft.NET.Workload.Emscripten.Current.Manifest-8.0.100" Version="8.0.29">
       <Uri>https://github.com/dotnet/emsdk</Uri>
-      <Sha>35ebe6f3e6953f878ed92f637ad8d7f27202f7a6</Sha>
+      <Sha>ac9f8092f4f527cb3ace4aac03f8d1dbadc39983</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.SourceBuild.Intermediate.emsdk" Version="8.0.28-servicing.26258.2">
+    <Dependency Name="Microsoft.SourceBuild.Intermediate.emsdk" Version="8.0.29-servicing.26303.5">
       <Uri>https://github.com/dotnet/emsdk</Uri>
-      <Sha>35ebe6f3e6953f878ed92f637ad8d7f27202f7a6</Sha>
+      <Sha>ac9f8092f4f527cb3ace4aac03f8d1dbadc39983</Sha>
       <SourceBuild RepoName="emsdk" ManagedOnly="true" />
     </Dependency>
     <Dependency Name="Microsoft.SourceBuild.Intermediate.source-build-assets" Version="8.0.0-alpha.1.26208.5">
@@ -112,79 +112,79 @@
     </Dependency>
   </ProductDependencies>
   <ToolsetDependencies>
-    <Dependency Name="Microsoft.DotNet.Arcade.Sdk" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.Arcade.Sdk" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
       <SourceBuild RepoName="arcade" ManagedOnly="true" />
     </Dependency>
     <Dependency Name="Microsoft.DotNet.XliffTasks" Version="1.0.0-beta.23475.1" CoherentParentDependency="Microsoft.DotNet.Arcade.Sdk">
       <Uri>https://github.com/dotnet/xliff-tasks</Uri>
       <Sha>73f0850939d96131c28cf6ea6ee5aacb4da0083a</Sha>
       <SourceBuild RepoName="xliff-tasks" ManagedOnly="true" />
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.Helix.Sdk" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.Helix.Sdk" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.GenAPI" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.GenAPI" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.GenFacades" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.GenFacades" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.XUnitExtensions" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.XUnitExtensions" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.XUnitConsoleRunner" Version="2.5.1-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.XUnitConsoleRunner" Version="2.5.1-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.Build.Tasks.Archives" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.Build.Tasks.Archives" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.Build.Tasks.Packaging" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.Build.Tasks.Packaging" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.Build.Tasks.Installers" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.Build.Tasks.Installers" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.Build.Tasks.Templating" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.Build.Tasks.Templating" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.Build.Tasks.Workloads" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.Build.Tasks.Workloads" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.CodeAnalysis" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.CodeAnalysis" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.Build.Tasks.TargetFramework" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.Build.Tasks.TargetFramework" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.RemoteExecutor" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.RemoteExecutor" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.Build.Tasks.Feed" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.Build.Tasks.Feed" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.VersionTools.Tasks" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.VersionTools.Tasks" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.SharedFramework.Sdk" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.SharedFramework.Sdk" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
     <Dependency Name="System.ComponentModel.TypeConverter.TestData" Version="8.0.0-beta.26153.1">
       <Uri>https://github.com/dotnet/runtime-assets</Uri>
@@ -335,9 +335,9 @@
       <Uri>https://github.com/dotnet/xharness</Uri>
       <Sha>28f5ed3a089ff1a179f523da0c910348e9010414</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.PackageTesting" Version="8.0.0-beta.26224.3">
+    <Dependency Name="Microsoft.DotNet.PackageTesting" Version="8.0.0-beta.26278.3">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>d9af20b993c474033098fe0851c2d71b4ecf434b</Sha>
+      <Sha>4b95fb1a9307265eb75f62d4937be50e6786e94e</Sha>
     </Dependency>
     <Dependency Name="optimization.windows_nt-x64.MIBC.Runtime" Version="1.0.0-prerelease.23566.3">
       <Uri>https://dev.azure.com/dnceng/internal/_git/dotnet-optimization</Uri>

eng/Versions.props

@@ -1,11 +1,11 @@
 <Project>
   <PropertyGroup>
     <!-- The .NET product branding version -->
-    <ProductVersion>8.0.28</ProductVersion>
+    <ProductVersion>8.0.29</ProductVersion>
     <!-- File version numbers -->
     <MajorVersion>8</MajorVersion>
     <MinorVersion>0</MinorVersion>
-    <PatchVersion>28</PatchVersion>
+    <PatchVersion>29</PatchVersion>
     <SdkBandVersion>8.0.100</SdkBandVersion>
     <PackageVersionNet7>7.0.20</PackageVersionNet7>
     <PackageVersionNet6>6.0.36</PackageVersionNet6>
@@ -88,21 +88,21 @@
     <!-- SDK dependencies -->
     <MicrosoftDotNetApiCompatTaskVersion>8.0.100</MicrosoftDotNetApiCompatTaskVersion>
     <!-- Arcade dependencies -->
-    <MicrosoftDotNetBuildTasksFeedVersion>8.0.0-beta.26224.3</MicrosoftDotNetBuildTasksFeedVersion>
-    <MicrosoftDotNetCodeAnalysisVersion>8.0.0-beta.26224.3</MicrosoftDotNetCodeAnalysisVersion>
-    <MicrosoftDotNetGenAPIVersion>8.0.0-beta.26224.3</MicrosoftDotNetGenAPIVersion>
-    <MicrosoftDotNetGenFacadesVersion>8.0.0-beta.26224.3</MicrosoftDotNetGenFacadesVersion>
-    <MicrosoftDotNetXUnitExtensionsVersion>8.0.0-beta.26224.3</MicrosoftDotNetXUnitExtensionsVersion>
-    <MicrosoftDotNetXUnitConsoleRunnerVersion>2.5.1-beta.26224.3</MicrosoftDotNetXUnitConsoleRunnerVersion>
-    <MicrosoftDotNetBuildTasksArchivesVersion>8.0.0-beta.26224.3</MicrosoftDotNetBuildTasksArchivesVersion>
-    <MicrosoftDotNetBuildTasksInstallersVersion>8.0.0-beta.26224.3</MicrosoftDotNetBuildTasksInstallersVersion>
-    <MicrosoftDotNetBuildTasksPackagingVersion>8.0.0-beta.26224.3</MicrosoftDotNetBuildTasksPackagingVersion>
-    <MicrosoftDotNetBuildTasksTargetFrameworkVersion>8.0.0-beta.26224.3</MicrosoftDotNetBuildTasksTargetFrameworkVersion>
-    <MicrosoftDotNetBuildTasksTemplatingVersion>8.0.0-beta.26224.3</MicrosoftDotNetBuildTasksTemplatingVersion>
-    <MicrosoftDotNetBuildTasksWorkloadsPackageVersion>8.0.0-beta.26224.3</MicrosoftDotNetBuildTasksWorkloadsPackageVersion>
-    <MicrosoftDotNetRemoteExecutorVersion>8.0.0-beta.26224.3</MicrosoftDotNetRemoteExecutorVersion>
-    <MicrosoftDotNetVersionToolsTasksVersion>8.0.0-beta.26224.3</MicrosoftDotNetVersionToolsTasksVersion>
-    <MicrosoftDotNetPackageTestingVersion>8.0.0-beta.26224.3</MicrosoftDotNetPackageTestingVersion>
+    <MicrosoftDotNetBuildTasksFeedVersion>8.0.0-beta.26278.3</MicrosoftDotNetBuildTasksFeedVersion>
+    <MicrosoftDotNetCodeAnalysisVersion>8.0.0-beta.26278.3</MicrosoftDotNetCodeAnalysisVersion>
+    <MicrosoftDotNetGenAPIVersion>8.0.0-beta.26278.3</MicrosoftDotNetGenAPIVersion>
+    <MicrosoftDotNetGenFacadesVersion>8.0.0-beta.26278.3</MicrosoftDotNetGenFacadesVersion>
+    <MicrosoftDotNetXUnitExtensionsVersion>8.0.0-beta.26278.3</MicrosoftDotNetXUnitExtensionsVersion>
+    <MicrosoftDotNetXUnitConsoleRunnerVersion>2.5.1-beta.26278.3</MicrosoftDotNetXUnitConsoleRunnerVersion>
+    <MicrosoftDotNetBuildTasksArchivesVersion>8.0.0-beta.26278.3</MicrosoftDotNetBuildTasksArchivesVersion>
+    <MicrosoftDotNetBuildTasksInstallersVersion>8.0.0-beta.26278.3</MicrosoftDotNetBuildTasksInstallersVersion>
+    <MicrosoftDotNetBuildTasksPackagingVersion>8.0.0-beta.26278.3</MicrosoftDotNetBuildTasksPackagingVersion>
+    <MicrosoftDotNetBuildTasksTargetFrameworkVersion>8.0.0-beta.26278.3</MicrosoftDotNetBuildTasksTargetFrameworkVersion>
+    <MicrosoftDotNetBuildTasksTemplatingVersion>8.0.0-beta.26278.3</MicrosoftDotNetBuildTasksTemplatingVersion>
+    <MicrosoftDotNetBuildTasksWorkloadsPackageVersion>8.0.0-beta.26278.3</MicrosoftDotNetBuildTasksWorkloadsPackageVersion>
+    <MicrosoftDotNetRemoteExecutorVersion>8.0.0-beta.26278.3</MicrosoftDotNetRemoteExecutorVersion>
+    <MicrosoftDotNetVersionToolsTasksVersion>8.0.0-beta.26278.3</MicrosoftDotNetVersionToolsTasksVersion>
+    <MicrosoftDotNetPackageTestingVersion>8.0.0-beta.26278.3</MicrosoftDotNetPackageTestingVersion>
     <!-- NuGet dependencies -->
     <NuGetBuildTasksPackVersion>6.0.0-preview.1.102</NuGetBuildTasksPackVersion>
     <!-- Installer dependencies -->
@@ -227,7 +227,7 @@
     <!-- ILLink -->
     <MicrosoftNETILLinkTasksVersion>8.0.0-rc.1.23406.6</MicrosoftNETILLinkTasksVersion>
     <!-- Mono Cecil -->
-    <MicrosoftDotNetCecilVersion>0.11.4-alpha.26158.1</MicrosoftDotNetCecilVersion>
+    <MicrosoftDotNetCecilVersion>0.11.4-alpha.26281.3</MicrosoftDotNetCecilVersion>
     <!-- ILCompiler -->
     <MicrosoftDotNetILCompilerVersion>8.0.0-rc.1.23406.6</MicrosoftDotNetILCompilerVersion>
     <!-- ICU -->
@@ -253,7 +253,7 @@
          Note: when the name is updated, make sure to update dependency name in eng/pipelines/common/xplat-setup.yml
                like - DarcDependenciesChanged.Microsoft_NET_Workload_Emscripten_Current_Manifest-8_0_100_Transport
     -->
-    <MicrosoftNETWorkloadEmscriptenCurrentManifest80100Version>8.0.28</MicrosoftNETWorkloadEmscriptenCurrentManifest80100Version>
+    <MicrosoftNETWorkloadEmscriptenCurrentManifest80100Version>8.0.29</MicrosoftNETWorkloadEmscriptenCurrentManifest80100Version>
     <MicrosoftNETRuntimeEmscriptenVersion>$(MicrosoftNETWorkloadEmscriptenCurrentManifest80100Version)</MicrosoftNETRuntimeEmscriptenVersion>
     <!-- SdkVersionForWorkloadTesting is used to compute the sdk band and version for workload testing.
          The published manifests are built in dotnet/sdk so these values are for testing purposes only.

global.json

@@ -8,9 +8,9 @@
     "dotnet": "8.0.126"
   },
   "msbuild-sdks": {
-    "Microsoft.DotNet.Arcade.Sdk": "8.0.0-beta.26224.3",
-    "Microsoft.DotNet.Helix.Sdk": "8.0.0-beta.26224.3",
-    "Microsoft.DotNet.SharedFramework.Sdk": "8.0.0-beta.26224.3",
+    "Microsoft.DotNet.Arcade.Sdk": "8.0.0-beta.26278.3",
+    "Microsoft.DotNet.Helix.Sdk": "8.0.0-beta.26278.3",
+    "Microsoft.DotNet.SharedFramework.Sdk": "8.0.0-beta.26278.3",
     "Microsoft.Build.NoTargets": "3.7.0",
     "Microsoft.Build.Traversal": "3.4.0",
     "Microsoft.NET.Sdk.IL": "8.0.0-rc.1.23406.6"

src/coreclr/nativeaot/System.Private.CoreLib/src/Internal/Runtime/CompilerHelpers/InteropHelpers.cs

@@ -45,7 +45,9 @@ internal static unsafe void StringToByValAnsiString(string str, byte* pNative, i
 
                 fixed (char* pManaged = str)
                 {
-                    PInvokeMarshal.StringToAnsiString(pManaged, lenUnicode, pNative, /*terminateWithNull=*/true, bestFit, throwOnUnmappableChar);
+                    PInvokeMarshal.StringToAnsiString(pManaged, lenUnicode, pNative,
+                        /*terminateWithNull=*/true, bestFit, throwOnUnmappableChar,
+                        nativeByteLength: charCount);
                 }
             }
             else

src/coreclr/nativeaot/System.Private.CoreLib/src/System/Runtime/InteropServices/PInvokeMarshal.cs

@@ -500,9 +500,14 @@ public static unsafe char AnsiCharToWideChar(byte nativeValue)
         }
 
         // c# string (UTF-16) to UTF-8 encoded byte array
+        // If specified, nativeByteLength represents the length of the output buffer and this function
+        // will not write more than that many bytes. If negative, this function writes as many bytes
+        // as needed to encode the string.
         internal static unsafe byte* StringToAnsiString(char* pManaged, int lenUnicode, byte* pNative, bool terminateWithNull,
-            bool bestFit, bool throwOnUnmappableChar)
+            bool bestFit, bool throwOnUnmappableChar, int nativeByteLength = -1)
         {
+            Debug.Assert(pNative != null || nativeByteLength == -1, "Native buffer should not be null when nativeByteLength is specified.");
+
             bool allAscii = Ascii.IsValid(new ReadOnlySpan<char>(pManaged, lenUnicode));
             int length;
 
@@ -515,6 +520,18 @@ public static unsafe char AnsiCharToWideChar(byte nativeValue)
                 length = GetByteCount(pManaged, lenUnicode);
             }
 
+            // Clamp to nativeByteLength when caller provides a bounded output buffer (ByValTStr).
+            // For non-ASCII, ConvertWideCharToMultiByte will throw (Unix) or truncate (Windows)
+            // when the encoded bytes exceed the clamped length. This matches CoreCLR behavior.
+            if (nativeByteLength >= 0)
+            {
+                int maxBytesToWrite = terminateWithNull ? Math.Max(0, nativeByteLength - 1) : nativeByteLength;
+                if (length > maxBytesToWrite)
+                {
+                    length = maxBytesToWrite;
+                }
+            }
+
             if (pNative == null)
             {
                 pNative = (byte*)Marshal.AllocCoTaskMem(checked(length + 1));
@@ -534,8 +551,8 @@ public static unsafe char AnsiCharToWideChar(byte nativeValue)
                                            throwOnUnmappableChar);
             }
 
-            // Zero terminate
-            if (terminateWithNull)
+            // Zero terminate if requested and the buffer is not specified to be size 0.
+            if (terminateWithNull && nativeByteLength != 0)
                 *(pNative + length) = 0;
 
             return pNative;