[Problem/Bug]: ARM64EC not linking

What happened?

When building using the ARM64EC platform using dynamic linking of WebView2, see various LNK2019 errors like the following:

error LNK2019: unresolved external symbol CreateCoreWebView2EnvironmentWithOptions referenced in function #CreateCoreWebView2EnvironmentWithOptions$exit_thunk (EC Symbol)

Traced to "build\Common.targets" in the NuGet package:

<EffectivePlatform Condition="'$(PlatformTarget)' == 'arm64'">arm64</EffectivePlatform>

This, overrides EffectivePlatform back to arm64 and thus the linker uses "build\native\arm64\WebView2Loader.dll.lib" instead of the intended "build\native\x64\WebView2Loader.dll.lib".

According to Visual Studio 2026 macro browser, for the ARM64EC solution platform:

• $(Platform): ARM64EC
• $(PlatformArchitecture): ARM64
• $(PlatformName): ARM64EC
• $(PlatformTarget): ARM64

Using this information, a simple workaround:

<EffectivePlatform Condition="'$(PlatformTarget)' == 'arm64' And '$(Platform)' != 'arm64ec'">arm64</EffectivePlatform>

Importance

Low. My app is not very affected, or this only affects development.

Runtime Channel

Stable release (WebView2 Runtime)

Runtime Version

142.0.3595.94

SDK Version

1.0.3595.46

Framework

Win32

Operating System

Windows 11

OS Version

26200.7093

Repro steps

Use WebView2 SDK to build Win32 WebView2APISample using the ARM64EC solution platform.

Repros in Edge Browser

No, issue does not reproduce in the corresponding Edge version

Regression

No, this never worked

Last working version (if regression)

No response

Start with build\Common.targets in the WebView2 SDK package and inspect how EffectivePlatform is selected for ARM64 and ARM64EC. Build the Win32 WebView2APISample using the ARM64EC solution platform, then verify that ARM64EC links against the x64 WebView2Loader library while ARM64 still uses the arm64 library.