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This must be done on a WoA machine - cross-compiling is not yet supported.
BUILDS ARE CURRENTLY BROKEN, PENDING THE FOLLOWING FIXES GOING INTO MSVC 17.7 PREVIEW 3:
https://developercommunity.visualstudio.com/t/Compiler-crash-C1001-when-libvpx-for-arm/10346110
https://developercommunity.visualstudio.com/t/Internal-Compiler-Error-when-building-ff/10396381
https://developercommunity.visualstudio.com/t/Certain-NEON-intrinsics-returning-incorr/10390423
This is because the latest non-preview version is broken for blender:
Compiling via build script
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There is a build script written, which takes care of many of the interim steps required to build and run the semi-release version of Blender, available here: https://gitlab.com/Linaro/windowsonarm/packages/blender/-/tree/master/
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