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MSVC v142 - VS 2019 C++ x64/x86 build tools (latest)
This is needed to make vsdevcmd.bat correctly setup LIB/LIBPATH/INCLUDE variables for x86->arm64 cross-compilation. All the lib/header files are actually present, but vsdevcmd.bat doesn’t add them without x86-hosted tools.
Installing this may become optional in the future
MSVC v142 - VS 2019 C++ ARM64 build tools (latest)
Without these vsdecmdvsdevcmd.bat doesn’t setup x86->arm64 cross-compilation.
C++ ATL for latest v142 build tools (ARM64)
LLVM uses needs ATL libraries for processing debug info
Windows 10 SDK
Versions 18362 and 19041 are known to work
Version 20348 is known to cause LLVM build failure
error: use of undeclared identifier '__umulh'
This is required for correct cross-compilation setup. Not sure if SDK libraries are actually used
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Recent versions of VS ship cmake as x86_64 binary (in VS circa-2020.08 cmake was x86_32 binary). Instead install the i386 build from https://cmake.org/downloadfiles/ and add that to user’s PATH. The following CMake + LLVM configurations are known
to work
LLVM 12, 13 + CMake 3.17
to break
LLVM 13 + CMake 3.22
Install Python
If you run “python” it takes you to the Windows Store which allegedly will give you a (native?) copy of Python3. As per usual with the Windows Store, it didn’t do anything when I clicked install.
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