When I added a TargetOS type to the build script, some BCL libraries failed to compile

[CeSun]

The TargetOS I added is based on linux-musl and adds a macro definition.
The submission record is as follows:
OpenHarmony-NET@435caa7

clr.aot can be compiled successfully.

But when compiling BCL, I get the following error:

/runtime/src/libraries/shims/System/src/System.cs(6,88): error CS0234: The type or namespace name 'ZLibException' does not exist in the namespace 'System.IO.Compression' (are you missing an assembly reference?) [/runtime/src/libraries/shims/System/src/System.csproj]
/runtime/src/libraries/shims/System/src/System.cs(7,77): error CS0234: The type or namespace name 'CookieVariant' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/runtime/src/libraries/shims/System/src/System.csproj]
/runtime/src/libraries/shims/System/src/System.cs(8,77): error CS0234: The type or namespace name 'PathList' does not exist in the namespace 'System.Net' (are you missing an assembly reference?) [/runtime/src/libraries/shims/System/src/System.csproj]
  mscorlib -> /runtime/artifacts/bin/mscorlib/Release/net9.0-openharmony/mscorlib.dll

After investigation, it is found that some cs codes of some libraries are not compiled
https://github.com/OpenHarmony-NET/runtime/blob/435caa71f6ea4ee5e7d13c9611d32730a4d4dcfa/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj#L3-L51

The value of TargetFramework here is .net9.0, which causes the value of TargetPlatformIdentifier to be '', which in turn causes some of the following cs files to not be compiled

But if you compile linux-musl, the value of TargetFramework here is .net9.0-unix

What affects TargetFramework? I didn't find a script to concatenate the ".net9,0-unix" string.

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[huoyaoyuan]

I see your addition of TargetsUnix and rid graph. The target framework expression net9.0-unix should be interpreted by the SDK. Do you have a copy of SDK that somehow knows openharmony->linux->unix? How about modifying RuntimeIdentifierGraph.json/PortableRuntimeIdentifierGraph.json in SDK root? Just a hint and I don't know much about this.

[CeSun]

Let msbuild and cmake know that openharmony is linux and unix configuration here:

https://github.com/OpenHarmony-NET/runtime/blob/435caa71f6ea4ee5e7d13c9611d32730a4d4dcfa/eng/native/configureplatform.cmake#L236-L241

https://github.com/OpenHarmony-NET/runtime/blob/435caa71f6ea4ee5e7d13c9611d32730a4d4dcfa/Directory.Build.props#L272-L293

I'm not sure if I'm missing any configuration