I installed 386 go 1.14.4 onto Windows 10 arm64 to C:\go. Then I cross compiled go 1.14.4 for Windows using CGO_ENABLED=0 GOOS=windows GOARCH=arm GOARM=7 ./make.bash, and then copied bin/ and pkg/ over to C:\go\bin and C:\go\pkg. Then I ran .\all.bat inside of the latest git master (e64675a as of writing) and kaboom:
I'd like to point out that we don't seem to have any Windows/ARM builders at the moment, and the person nominally listed as the Windows/ARM port owner seems to be MIA. It is hard to see how to work on this bug without a functioning builder.