Remove hardcoded TFM in wasm build files

[ViktorHofer]

The WasmAppNative.targets file hardcodes the TFM in two places:

• https://github.com/dotnet/runtime/blob/main/src/mono/wasm/build/WasmApp.Native.targets#L283

• runtime/src/mono/wasm/build/WasmApp.Native.targets

  Line 555 in 41f57b7

  <_WasmAOTSearchPaths Include="$(MicrosoftNetCoreAppRuntimePackRidDir)\lib\net7.0" />

This makes reving the TFM i.e., from net7.0 to net8.0 harder. Also, this component is shipping to customers and should use by the SDK provided values instead.

runtime/src/mono/wasm/build/WasmApp.targets

Line 223 in 41f57b7

<MicrosoftNetCoreAppRuntimePackDir Condition="'$(MicrosoftNetCoreAppRuntimePackDir)' == ''">%(ResolvedRuntimePack.PackageDirectory)</MicrosoftNetCoreAppRuntimePackDir>

uses the SDK provided ResolvedRuntimePack msbuild item. Even though that item itself doesn't offer a metadata that informs about the matching TFM, another item in the SDK should be available, i.e. KnownRuntimePack that includes the TargetFramework as metadata.

Noticed in #78354

cc @radical

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Issue Details

---

The WasmAppNative.targets file hardcodes the TFM in two places:

• https://github.com/dotnet/runtime/blob/main/src/mono/wasm/build/WasmApp.Native.targets#L283

• runtime/src/mono/wasm/build/WasmApp.Native.targets

  Line 555 in 41f57b7

  <_WasmAOTSearchPaths Include="$(MicrosoftNetCoreAppRuntimePackRidDir)\lib\net7.0" />

This makes reving the TFM i.e., from net7.0 to net8.0 harder. Also, this component is shipping to customers and should use by the SDK provided values instead.

runtime/src/mono/wasm/build/WasmApp.targets

Line 223 in 41f57b7

<MicrosoftNetCoreAppRuntimePackDir Condition="'$(MicrosoftNetCoreAppRuntimePackDir)' == ''">%(ResolvedRuntimePack.PackageDirectory)</MicrosoftNetCoreAppRuntimePackDir>

uses the SDK provided ResolvedRuntimePack msbuild item. Even though that item itself doesn't offer a metadata that informs about the matching TFM, another item in the SDK should be available, i.e. KnownRuntimePack that includes the TargetFramework as metadata.

Noticed in #78354

cc @radical

Author:	ViktorHofer
Assignees:	radical
Labels:	arch-wasm, untriaged, area-Build-mono
Milestone:	-

[radical]

Also, this component is shipping to customers and should use by the SDK provided values instead.

runtime/src/mono/wasm/build/WasmApp.targets

Line 223 in 41f57b7

<MicrosoftNetCoreAppRuntimePackDir Condition="'$(MicrosoftNetCoreAppRuntimePackDir)' == ''">%(ResolvedRuntimePack.PackageDirectory)</MicrosoftNetCoreAppRuntimePackDir>

uses the SDK provided ResolvedRuntimePack msbuild item. Even though that item itself doesn't offer a metadata that informs about the matching TFM, another item in the SDK should be available, i.e. KnownRuntimePack that includes the TargetFramework as metadata.

How do I find the "matching" KnownRuntimePack item from the available ResolvedRuntimePack?