Fresh install: Internal errors: `Load redeclared in this block`

[xobs]

What version of Go are you using (go version)?

[12:33:33 PM] D:/Code/hello-go> go version
go version go1.16.5 windows/amd64
[12:34:01 PM] D:/Code/hello-go>

Does this issue reproduce with the latest release?

I just downloaded this install from https://golang.org/doc/install -- I'm not sure if there's a newer release

What operating system and processor architecture are you using (go env)?

go env Output

[12:34:01 PM] D:/Code/hello-go> go env
set GO111MODULE=
set GOARCH=amd64
set GOBIN=
set GOCACHE=C:\Users\smcro\AppData\Local\go-build
set GOENV=C:\Users\smcro\AppData\Roaming\go\env
set GOEXE=.exe
set GOFLAGS=
set GOHOSTARCH=amd64
set GOHOSTOS=windows
set GOINSECURE=
set GOMODCACHE=C:\Users\smcro\go\pkg\mod
set GONOPROXY=
set GONOSUMDB=
set GOOS=windows
set GOPATH=C:\Users\smcro\go
set GOPRIVATE=
set GOPROXY=https://proxy.golang.org,direct
set GOROOT=D:\Software\Go
set GOSUMDB=sum.golang.org
set GOTMPDIR=
set GOTOOLDIR=D:\Software\Go\pkg\tool\windows_amd64
set GOVCS=
set GOVERSION=go1.16.5
set GCCGO=gccgo
set AR=ar
set CC=gcc
set CXX=g++
set CGO_ENABLED=1
set GOMOD=D:\Code\hello-go\go.mod
set CGO_CFLAGS=-g -O2
set CGO_CPPFLAGS=
set CGO_CXXFLAGS=-g -O2
set CGO_FFLAGS=-g -O2
set CGO_LDFLAGS=-g -O2
set PKG_CONFIG=pkg-config
set GOGCCFLAGS=-m64 -mthreads -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=C:\Users\smcro\AppData\Local\Temp\go-build60325066=/tmp/go-build -gno-record-gcc-switches
[12:34:49 PM] D:/Code/hello-go>

What did you do?

I'm following the steps on https://golang.org/doc/tutorial/getting-started

1. Install Go
2. Open a new terminal window
3. Create a new directory
4. Run go mod init example.com/hello
5. Create hello.go
6. Type go run .

What did you expect to see?

I expect to see it saying Hello, World!

What did you see instead?

[12:33:04 PM] D:/Code> mkdir hello-go

    Directory: D:\Code

Mode                 LastWriteTime         Length Name
----                 -------------         ------ ----
d----           26/6/2021 12:33 PM                hello-go

[12:33:06 PM] D:/Code> cd .\hello-go\
[12:33:07 PM] D:/Code/hello-go> go mod init example.com/hello
go: creating new go.mod: module example.com/hello
[12:33:12 PM] D:/Code/hello-go> code .
[12:33:19 PM] D:/Code/hello-go> go run .
# runtime/internal/atomic
D:\Software\Go\src\runtime\internal\atomic\atomic_amd64x.go:13:6: Load redeclared in this block
        previous declaration at D:\Software\Go\src\runtime\internal\atomic\atomic_amd64.go:16:24
D:\Software\Go\src\runtime\internal\atomic\atomic_amd64x.go:19:6: Loadp redeclared in this block
        previous declaration at D:\Software\Go\src\runtime\internal\atomic\atomic_amd64.go:22:32
D:\Software\Go\src\runtime\internal\atomic\atomic_amd64x.go:25:6: Load64 redeclared in this block
        previous declaration at D:\Software\Go\src\runtime\internal\atomic\atomic_amd64.go:28:26
D:\Software\Go\src\runtime\internal\atomic\atomic_amd64x.go:30:6: Xadd redeclared in this block
        previous declaration at D:\Software\Go\src\runtime\internal\atomic\atomic_amd64.go:51:37
D:\Software\Go\src\runtime\internal\atomic\atomic_amd64x.go:33:6: Xadd64 redeclared in this block
        previous declaration at D:\Software\Go\src\runtime\internal\atomic\atomic_amd64.go:54:39
D:\Software\Go\src\runtime\internal\atomic\atomic_amd64x.go:36:6: Xadduintptr redeclared in this block
        previous declaration at D:\Software\Go\src\runtime\internal\atomic\atomic_amd64.go:57:47
D:\Software\Go\src\runtime\internal\atomic\atomic_amd64x.go:39:6: Xchg redeclared in this block
        previous declaration at D:\Software\Go\src\runtime\internal\atomic\atomic_amd64.go:60:36
D:\Software\Go\src\runtime\internal\atomic\atomic_amd64x.go:42:6: Xchg64 redeclared in this block
        previous declaration at D:\Software\Go\src\runtime\internal\atomic\atomic_amd64.go:63:38
D:\Software\Go\src\runtime\internal\atomic\atomic_amd64x.go:45:6: Xchguintptr redeclared in this block
        previous declaration at D:\Software\Go\src\runtime\internal\atomic\atomic_amd64.go:66:45
D:\Software\Go\src\runtime\internal\atomic\atomic_amd64x.go:48:6: And8 redeclared in this block
        previous declaration at D:\Software\Go\src\runtime\internal\atomic\atomic_amd64.go:75:27
D:\Software\Go\src\runtime\internal\atomic\atomic_amd64x.go:48:6: too many errors
[12:34:49 PM] D:/Code/hello-go> Get-Command go

CommandType     Name                                               Version    Source
-----------     ----                                               -------    ------
Application     go.exe                                             0.0.0.0    D:\Software\Go\bin\go.exe

[12:39:40 PM] D:/Code/hello-go> more .\hello.go
package main

import "fmt"

func main() {
    fmt.Println("Hello, World!")
}
[12:39:46 PM] D:/Code/hello-go>

Most online forums seem to indicate this is a problem with the install, however this is a fresh install. I don't know that I'm doing anything incorrect with the installation steps. The error also is not very helpful, and should probably be improved.

[martisch]

This usually happens if an existing (older version) of Go was already installed and the new installation just added files to it. So this might not have been a fresh install. The file src\runtime\internal\atomic\atomic_amd64x.go doesnt exist in go1.16.5 but was used in a previous version of Go. Please delete the installation and folder at D:\Software\Go\ and try a new fresh installation of Go.

[xobs]

I deleted the directory and recreated it, which fixed the symptoms.

However, how can the error case be improved? There was no warning during the install, and the resulting error wasn't helpful in determining the error.

I think this could be improved in two ways:

1. Fix the error when this situation is encountered. # runtime/internal/atomic seems like a bug in the compiler, and doesn't give any indication that there are duplicate files. In fact, in the list of files, the same file is listed multiple times, which is very confusing.
2. Fix the installer. It should display a warning if a directory is selected that already contains an installation. Alternately, it should offer to remove the directory, or refuse to install. Python is an example of a language installer that does this.

[martisch]

1. runtime/internal/atomic is not a bug in the compiler. It is not allowed in the Go language to have multiple declarations of the same name. This could be a user error in any package by e.g. declaring main twice. The same file is listed multiple times for different duplicate declarations on different lines. It is generally helpful to keep parsing/compiling if possible and report multiple errors to avoid frequent recompiles only knowing about one error each time.

2. This sound like the root cause but it seems the MSI installer should already do that? https://go-review.googlesource.com/c/build/+/48010/ Was the previous installation also done through the MSI installer on the current Windows installation?

[akyunus]

I had the same issue. I had Go version 1.11 which was installed without MSI. I used the MSI installer to install go version 1.16.5 windows/amd64 to the same directory. No warnings displayed. I got the same atomic_amd64x.go errors. I deleted the directory. Repaired the installation with the MSI installer. That's seems working normal now.