Building runtime on ARM64 uses x86 tools?

[vcsjones]

When I build the runtime on an ARM64 Windows machine using .\build.cmd -rc release -s clr (and cleaning artifacts first), I noticed it using native compilation tools from C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.38.33130\bin\Hostx86\arm64.

According to the task manager, the compiler and linker tooling in this directory is x86, so it's using emulation.

I would expect the build to use tools in the directory C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.38.33130\bin\Hostarm64\arm64

Which contains native ARM64 build tools.

When I forced the build to use the native ARM64 tooling, there is a non-trivial performance improvement in compilation speed. The ARM64 tooling takes 8m52s whereas the x86 tooling takes 13m21s.

[ghost]

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Issue Details

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When I build the runtime on an ARM64 Windows machine using `.\build.cmd -rc release -s clr` (and cleaning artifacts first), I noticed it using native compilation tools from `C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.38.33130\bin\Hostx86\arm64`. According to the task manager, the compiler and linker tooling in this directory is x86, so it's using emulation. I would expect the build to use tools in the directory `C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.38.33130\bin\Hostarm64\arm64` Which contains native ARM64 build tools. When I forced the build to use the native ARM64 tooling, there is a non-trivial performance improvement in compilation speed. The ARM64 tooling takes 8m52s whereas the x86 tooling takes 13m21s.

Author:	vcsjones
Assignees:	-
Labels:	`area-Infrastructure`
Milestone:	-

[jkotas]

Related #76516