Cross-platform windows images don't load

docker buildx doesn't seem to be working for building windows platform images from linux.

Building from an amd64/linux machine, the following commands all complete successfully (although the two linux commands have a couple seconds in the "importing to docker" step, where in the windows command it's zero seconds).

$ docker buildx build --platform linux/arm64 --build-arg TARGETPLATFORM=linux/arm64 --build-arg ARCH=arm64 --build-arg BASE_IMAGE=debian --build-arg BINARY=multiarch-test -t local_ws_prefix/multiarch-test-arm64-linux:test . --load
$ docker buildx build --platform linux/amd64 --build-arg TARGETPLATFORM=linux/amd64 --build-arg ARCH=amd64 --build-arg BASE_IMAGE=debian --build-arg BINARY=multiarch-test -t local_ws_prefix/multiarch-test-amd64-linux:test . --load
$ docker buildx build --platform windows/amd64 --build-arg TARGETPLATFORM=windows/amd64 --build-arg ARCH=amd64 --build-arg BASE_IMAGE=mcr.microsoft.com/windows/servercore:10.0.19042.685 --build-arg BINARY=multiarch-test.exe -t local_ws_prefix/multiarch-test-amd64-windows:test . --load

But only the two linux images appear:

$ docker images | grep local_ws_prefix
local_ws_prefix/multiarch-test-amd64-linux                                             test                                   5631c29885e7   8 minutes ago       126MB
local_ws_prefix/multiarch-test-arm64-linux                                             test                                   eebed83554f0   11 minutes ago      120MB

I expected either the windows command to produce an image, or to not complete successfully.

Here's the dockerfile and a main.go; drop them both into a directory and run go mod init multiarch-test

Dockerfile

ARG TARGETPLATFORM
ARG BINARY
ARG BASE_IMAGE

FROM --platform=linux/amd64 golang:1.16 AS builder

WORKDIR /code
ADD . /code/
RUN cd /code/ && mkdir -p bin && GOOS=$(echo $TARGETPLATFORM | cut -f1 -d '/') GOARCH=$(echo $TARGETPLATFORM | cut -f2 -d '/') go build  -o bin/$BINARY .

FROM ${BASE_IMAGE}
LABEL description="PD CSI driver"
COPY --from=builder /code/bin/$BINARY /$BINARY

main.go

package main

import (
	"fmt"
	"runtime"
)

func main() {
	fmt.Println(runtime.GOOS)
}

Reproduce the three docker buildx build commands using the provided Dockerfile and main.go, then compare the Windows result with docker images. Start by tracing the --load behavior for the windows/amd64 build; done means the command either loads a usable Windows image or reports the failure instead of completing silently.