two-phase name lookup is not supported for C++/CLl or C++/CX; use /Zc:twoPhase #5237

liukuo362573 · 2026-05-02T04:24:39Z

liukuo362573
May 2, 2026

CefSharp Version

146.0.100

Operating System

Windows 11

Architecture

x64

.Net Version

.net 6.0

Implementation

WPF

Reproduction Steps

I use Visual Studio 2022 to compile v146.0.100
I have this compile error on both windows 10 and windows 11.

two-phase name lookup is not supported for C++/CLl or C++/CX; use /Zc:twoPhase

amaitland · 2026-05-02T22:21:38Z

amaitland
May 2, 2026
Maintainer

Converted to discussion as this is more likely an issue with your build environment than it is a bug.

I've not seen any issues building locally, CI builds worked. From the PR's that have been submitted recently, nobody has reported an issue. So you are probably missing some tools from your VS install.

I'm using

Microsoft Visual Studio Community 2022 (64-bit) - Current
Version 17.14.30

Make sure you have the Desktop Development with C++ workload installed.

https://github.com/cefsharp/CefSharp/blob/master/.vsconfig

1 reply

amaitland May 4, 2026
Maintainer

Here is a dump (.vsconfig export) of what I have installed on my machine. You won't need all the mac/android components as CefSharp is windows only.

{
  "version": "1.0",
  "components": [
    "android",
    "aspire",
    "Component.Microsoft.VisualStudio.LiveShare.2022",
    "Component.Microsoft.VisualStudio.RazorExtension",
    "Component.Microsoft.VisualStudio.Web.AzureFunctions",
    "Component.Microsoft.Web.LibraryManager",
    "Component.Microsoft.WebTools.BrowserLink.WebLivePreview",
    "Component.OpenJDK",
    "Component.VisualStudio.GitHub.Copilot",
    "ComponentGroup.Microsoft.NET.AppModernization",
    "ios",
    "maccatalyst",
    "maui.blazor",
    "maui.core",
    "maui.windows",
    "Microsoft.Component.ClickOnce",
    "Microsoft.Component.MSBuild",
    "Microsoft.Component.NetFX.Native",
    "Microsoft.ComponentGroup.Blend",
    "Microsoft.ComponentGroup.ClickOnce.Publish",
    "Microsoft.Net.Component.4.6.2.TargetingPack",
    "Microsoft.Net.Component.4.7.2.TargetingPack",
    "Microsoft.Net.Component.4.8.SDK",
    "Microsoft.Net.Component.4.8.TargetingPack",
    "Microsoft.Net.ComponentGroup.4.8.DeveloperTools",
    "Microsoft.Net.ComponentGroup.DevelopmentPrerequisites",
    "Microsoft.Net.ComponentGroup.TargetingPacks.Common",
    "microsoft.net.runtime.android",
    "microsoft.net.runtime.android.aot",
    "microsoft.net.runtime.android.aot.net8",
    "microsoft.net.runtime.android.net8",
    "microsoft.net.runtime.ios",
    "microsoft.net.runtime.maccatalyst",
    "microsoft.net.runtime.mono.tooling",
    "microsoft.net.runtime.mono.tooling.net7",
    "microsoft.net.runtime.mono.tooling.net8",
    "Microsoft.NetCore.Component.DevelopmentTools",
    "Microsoft.NetCore.Component.Runtime.3.1",
    "Microsoft.NetCore.Component.Runtime.5.0",
    "Microsoft.NetCore.Component.Runtime.6.0",
    "Microsoft.NetCore.Component.Runtime.8.0",
    "Microsoft.NetCore.Component.Runtime.9.0",
    "Microsoft.NetCore.Component.SDK",
    "Microsoft.NetCore.Component.Web",
    "Microsoft.VisualStudio.Component.AppInsights.Tools",
    "Microsoft.VisualStudio.Component.Common.Azure.Tools",
    "Microsoft.VisualStudio.Component.CoreEditor",
    "Microsoft.VisualStudio.Component.CppBuildInsights",
    "Microsoft.VisualStudio.Component.Debugger.JustInTime",
    "Microsoft.VisualStudio.Component.DiagnosticTools",
    "Microsoft.VisualStudio.Component.DockerTools",
    "Microsoft.VisualStudio.Component.DotNetModelBuilder",
    "Microsoft.VisualStudio.Component.EntityFramework",
    "Microsoft.VisualStudio.Component.FSharp",
    "Microsoft.VisualStudio.Component.FSharp.WebTemplates",
    "Microsoft.VisualStudio.Component.Graphics",
    "Microsoft.VisualStudio.Component.Graphics.Tools",
    "Microsoft.VisualStudio.Component.IISExpress",
    "Microsoft.VisualStudio.Component.IntelliCode",
    "Microsoft.VisualStudio.Component.JavaScript.Diagnostics",
    "Microsoft.VisualStudio.Component.JavaScript.TypeScript",
    "Microsoft.VisualStudio.Component.ManagedDesktop.Core",
    "Microsoft.VisualStudio.Component.ManagedDesktop.Prerequisites",
    "Microsoft.VisualStudio.Component.MSODBC.SQL",
    "Microsoft.VisualStudio.Component.MSSQL.CMDLnUtils",
    "Microsoft.VisualStudio.Component.NuGet",
    "Microsoft.VisualStudio.Component.Roslyn.Compiler",
    "Microsoft.VisualStudio.Component.Roslyn.LanguageServices",
    "Microsoft.VisualStudio.Component.SQL.CLR",
    "Microsoft.VisualStudio.Component.SQL.DataSources",
    "Microsoft.VisualStudio.Component.SQL.LocalDB.Runtime",
    "Microsoft.VisualStudio.Component.SQL.SSDT",
    "Microsoft.VisualStudio.Component.TextTemplating",
    "Microsoft.VisualStudio.Component.TypeScript.TSServer",
    "Microsoft.VisualStudio.Component.VC.14.29.16.11.CLI.Support",
    "Microsoft.VisualStudio.Component.VC.14.29.16.11.x86.x64",
    "Microsoft.VisualStudio.Component.VC.ASAN",
    "Microsoft.VisualStudio.Component.VC.ATL",
    "Microsoft.VisualStudio.Component.VC.CLI.Support",
    "Microsoft.VisualStudio.Component.VC.CMake.Project",
    "Microsoft.VisualStudio.Component.VC.CoreIde",
    "Microsoft.VisualStudio.Component.VC.DiagnosticTools",
    "Microsoft.VisualStudio.Component.VC.Redist.14.Latest",
    "Microsoft.VisualStudio.Component.VC.TestAdapterForBoostTest",
    "Microsoft.VisualStudio.Component.VC.TestAdapterForGoogleTest",
    "Microsoft.VisualStudio.Component.VC.Tools.ARM64",
    "Microsoft.VisualStudio.Component.VC.Tools.ARM64EC",
    "Microsoft.VisualStudio.Component.VC.Tools.x86.x64",
    "Microsoft.VisualStudio.Component.Vcpkg",
    "Microsoft.VisualStudio.Component.Web",
    "Microsoft.VisualStudio.Component.WebDeploy",
    "Microsoft.VisualStudio.Component.Windows10SDK",
    "Microsoft.VisualStudio.Component.Windows10SDK.19041",
    "Microsoft.VisualStudio.Component.Windows11SDK.22621",
    "Microsoft.VisualStudio.Component.Windows11SDK.26100",
    "Microsoft.VisualStudio.Component.Windows11Sdk.WindowsPerformanceToolkit",
    "Microsoft.VisualStudio.Component.WindowsAppSdkSupport.CSharp",
    "Microsoft.VisualStudio.Component.WslDebugging",
    "Microsoft.VisualStudio.ComponentGroup.AzureFunctions",
    "Microsoft.VisualStudio.ComponentGroup.Maui.All",
    "Microsoft.VisualStudio.ComponentGroup.Maui.Android",
    "Microsoft.VisualStudio.ComponentGroup.Maui.Blazor",
    "Microsoft.VisualStudio.ComponentGroup.Maui.iOS",
    "Microsoft.VisualStudio.ComponentGroup.Maui.MacCatalyst",
    "Microsoft.VisualStudio.ComponentGroup.Maui.Shared",
    "Microsoft.VisualStudio.ComponentGroup.Maui.Windows",
    "Microsoft.VisualStudio.ComponentGroup.MSIX.Packaging",
    "Microsoft.VisualStudio.ComponentGroup.NativeDesktop.Core",
    "Microsoft.VisualStudio.ComponentGroup.UWP.NetCoreAndStandard",
    "Microsoft.VisualStudio.ComponentGroup.Web",
    "Microsoft.VisualStudio.ComponentGroup.Web.CloudTools",
    "Microsoft.VisualStudio.ComponentGroup.WebToolsExtensions",
    "Microsoft.VisualStudio.ComponentGroup.WebToolsExtensions.CMake",
    "Microsoft.VisualStudio.ComponentGroup.WebToolsExtensions.TemplateEngine",
    "Microsoft.VisualStudio.ComponentGroup.WindowsAppDevelopment.Prerequisites",
    "Microsoft.VisualStudio.ComponentGroup.WindowsAppSDK.Cs",
    "Microsoft.VisualStudio.Workload.CoreEditor",
    "Microsoft.VisualStudio.Workload.ManagedDesktop",
    "Microsoft.VisualStudio.Workload.NativeDesktop",
    "Microsoft.VisualStudio.Workload.NetCrossPlat",
    "Microsoft.VisualStudio.Workload.NetWeb",
    "Microsoft.VisualStudio.Workload.Universal",
    "runtimes.ios",
    "runtimes.maccatalyst"
  ],
  "extensions": []
}

liukuo362573 · 2026-05-03T23:12:49Z

liukuo362573
May 3, 2026
Author

@amaitland Hi,thanks for your reply very much.I will try again.

0 replies

liukuo362573 · 2026-05-04T10:33:15Z

liukuo362573
May 4, 2026
Author

@amaitland Thanks very much, After I upgrade my visual studio,it build successfully.
This project is very useful,it is a great project!

0 replies

abrahamranardo · 2026-05-05T15:55:36Z

abrahamranardo
May 5, 2026

@amaitland I’m using Visual Studio 2026 (18.5.2) and encountered the same issue.
It turns out that VS2026 isn’t properly handled in CefSharp.props. The file uses exact equality checks (== '17.0') for VisualStudioVersion, so any version newer than 2022 silently falls back to the VS2019 defaults.

On Visual Studio 2026 (VisualStudioVersion = 18.0), this leads to two build failures:

Compiler errors (C++/CLI projects)
PlatformToolset falls back to v142 (VS2019 toolset), which does not support the C++20 constructs used in CEF SDK 146 headers (e.g., concept, operator<=>) when compiling in C++/CLI mode:

  error C2061: syntax error: identifier 'IsRefCountedType'   (cef_ref_counted.h)
  error C2059: syntax error: '>'                             (cef_scoped_refptr.h)
  error C2473: 'operator <=': looks like a function definition, but there is no parameter list.

Linker error
VisualStudioProductVersion remains set to 2019, causing the linker to look for libcef_dll_wrapper.lib in the base CEF folder.
However, CEF SDK 146 only provides a VS2022-compiled version of this library (under a VS2022/ subfolder), so the file cannot be found:

error LNK1181: cannot open input file 'libcef_dll_wrapper.lib'

This can be resolved by updating the CefSharp.props conditions from strict equality (== '17.0') to a greater-than-or-equal check (>= '17.0').
Before

  <VisualStudioProductVersion Condition="'$(VisualStudioVersion)'=='17.0' AND
  Exists(...\VS2022\libcef_dll_wrapper.lib')">2022</VisualStudioProductVersion>
  <PlatformToolset Condition="'$(VisualStudioVersion)'=='17.0'">v143</PlatformToolset>

After

  <VisualStudioProductVersion Condition="'$(VisualStudioVersion)'>='17.0' AND
  Exists(...\VS2022\libcef_dll_wrapper.lib')">2022</VisualStudioProductVersion>
  <PlatformToolset Condition="'$(VisualStudioVersion)'>='17.0'">v143</PlatformToolset>

0 replies

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liukuo362573 May 2, 2026

CefSharp Version

Operating System

Architecture

.Net Version

Implementation

Reproduction Steps

Replies: 4 comments · 1 reply

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amaitland May 2, 2026 Maintainer

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abrahamranardo May 5, 2026

liukuo362573
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amaitland
May 2, 2026
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amaitland May 4, 2026
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May 3, 2026
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May 4, 2026
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abrahamranardo
May 5, 2026