llvm-msvc is a compiler based on LLVM that isn't limited by MSVC. The aim is to provide the same experience as MSVC on Windows. You can use naked functions anywhere and also add custom support like obfuscation.

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• Compatible with MSVC syntax as much as possible.
• Improved SEH stability.
• Added some special Intrinsic functions(__vmx_vmread/__vmx_write).
• Supports x64/ARM64 windows drivers.
• Supports AArch64 android GKI drivers.
• Allows naked X64 inline asm.
• Enables multiple cores compilation.
• Supports /MP when precompiled headers are present.
• Supports /GL (LTO optimization).

• Clang follows the GCC standard, while MSVC has its own unique syntax.
• Some of the code is pretty hacky. Can't submit it officially.
• Waiting for the official fix takes too long.

• Install Visual Studio 2015-2022 (I recommend using 2022) along with WDK11.
• Download and install llvm-msvc from the following repository llvm-msvc_X86_64_installer-PDB.exe.
• Create your Windows driver project and choose "LLVM-MSVC_v143_KernelMode" as your platform toolset.
• Compile your project.

X86+ARM64：clang+lld+lldb+debug
cmake -Bbuild -A X64 -DLLDB_ENABLE_PYTHON=OFF -DLLVM_ENABLE_PROJECTS="clang;lld;lldb" -DCMAKE_INSTALL_PREFIX=E:\llvm\install-debug-64 -DLLVM_TARGETS_TO_BUILD="X86;AArch64" -DCMAKE_BUILD_TYPE=Debug llvm
msbuild /m -p:Configuration=Debug INSTALL.vcxproj 
--------------------------------------------------
X86+ARM64：clang+lld+lldb+RelWithDebInfo
mkdir build2
pushd build2
cmake .. -G "Visual Studio 17 2022" -A X64 -DLLVM_ENABLE_PACK_PDB=ON -DLLDB_ENABLE_PYTHON=OFF -DLLVM_ENABLE_PROJECTS="clang;lld;lldb" -DCMAKE_INSTALL_PREFIX=E:\llvm\install-RelWithDebInfo-64 -DLLVM_ENABLE_LIBXML2=OFF -DLLVM_ENABLE_ZLIB=OFF -DLLVM_TARGETS_TO_BUILD="X86;AArch64" -DCMAKE_BUILD_TYPE=RelWithDebInfo -DLLVM_USE_CRT_RELEASE=MT ../llvm
msbuild /m -p:Configuration=RelWithDebInfo INSTALL.vcxproj 
--------------------------------------------------
X86+ARM64：clang+lld+lldb+release
mkdir build3
pushd build3
cmake .. -G "Visual Studio 17 2022" -A X64 -DLLDB_ENABLE_PYTHON=OFF -DLLVM_ENABLE_PROJECTS="clang;lld;lldb" -DCMAKE_INSTALL_PREFIX=E:\llvm\install-release-64 -DLLVM_ENABLE_LIBXML2=OFF -DLLVM_ENABLE_ZLIB=OFF -DLLVM_TARGETS_TO_BUILD="X86;AArch64" -DCMAKE_BUILD_TYPE=release -DLLVM_USE_CRT_RELEASE=MT ../llvm
msbuild /m -p:Configuration=release INSTALL.vcxproj 

• https://github.com/HyunCafe/contribute-practice
• https://docs.github.com/en/get-started/quickstart/contributing-to-projects

If you don't know how to learn LLVM, you can check out this repository of mine.

Yes.

No.

• LLVM
• Some anonymous people