Build zstd with /source-charset:utf-8 option

[kzrnm]

Fix #124474

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[akoeplinger]

I think we should rather pass /source-charset:utf-8 to the zstd build instead of changing the upstream sources

[am11]

Is the issue only in coreclr build (which separately includes this project) or src/native/libs/build-native.cmd (the main native libs entrypoint) also fails?

In either case, it's confusing; if this is actually fixing the build, I’m not sure why this setting isn’t being picked up or inherited:

runtime/eng/native/configurecompiler.cmake

Line 942 in 95b3ea0

add_compile_options($<$<COMPILE_LANGUAGE:C,CXX>:/source-charset:utf-8>) # Force MSVC to compile source as UTF-8.

cc @jkoritzinsky

[am11]

I think we should rather pass /source-charset:utf-8 to the zstd build instead of changing the upstream sources

The .cmake files at the src/native/external level are ours. The ones in the subdirectories below that are vendor-specific.

[jkotas]

I think we should rather pass /source-charset:utf-8 to the zstd build instead of changing the upstream sources

I would propose a PR for upstream as well. Non-ASCII characters in C/C++ sources are endless source of pain.

[akoeplinger]

In either case, it's confusing; if this is actually fixing the build, I’m not sure why this setting isn’t being picked up or inherited:

runtime/eng/native/configurecompiler.cmake

Line 942 in 95b3ea0

add_compile_options($<$<COMPILE_LANGUAGE:C,CXX>:/source-charset:utf-8>) # Force MSVC to compile source as UTF-8.

hm yeah that's a good question

[rzikm]

/ba-g build failures are unrelated

[rzikm]

Thanks!