Build target `arm64ec-pc-windows-msvc` with `-Zbuild-std` got linking error.

[Wyvern]

Build project target arm64ec-pc-windows-msvc with -Zbuild-std on x86-64 windows host got linking error message like below:

lld: error: msvcrt.lib(tlssup.obj): machine type arm64 conflicts with arm64ec␍

How to fix it?

[dpaoliello]

What version of Rust are you using?
What version of the Windows SDK do you have?

[Wyvern]

@dpaoliello
Using latest Rust nightly version 1.83
Not sure the exact Windows SDK version pre-installed, using github CI free tier windows server 2022 host.

building without -Zbuild-std successfully, but failed with it.

[ChrisDenton]

It's perhaps unrelated but apparently build-std has been failing since nightly-2024-08-24 with a different error.

[dpaoliello]

Oh, I just realized, that's an error coming from lld - currently the only supported toolchain to use for ARM64EC is MSVC.

While Clang 19 can build ARM64EC code, lld's support for ARM64EC is still being worked on.

[Wyvern]

So, build-std for arm64ec can NOT be done for now, or is there a workaround about it?

[dpaoliello]

It's perhaps unrelated but apparently build-std has been failing since nightly-2024-08-24 with a different error.

I'm following up in #126349 about that, but it looks like the root cause is because it's building on Linux.

So, build-std for arm64ec can NOT be done for now, or is there a workaround about it?

Is there a way you can avoid using lld? I don't know why Rust would pick that over link...

[Wyvern]

Ok, avoid lld linker.

[target.arm64ec-pc-windows-msvc]
linker = "link.exe"

will try it...