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

go1.13.4 linux/amd64

Does this issue reproduce with the latest release?

Yes

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

$ go env
GO111MODULE=""
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/mikerah/snap/code/common/.cache/go-build"
GOENV="/home/mikerah/.config/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/home/mikerah/go"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/usr/local/go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/local/go/pkg/tool/linux_amd64"
GCCGO="gccgo"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD=""
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build515948109=/tmp/go-build -gno-record-gcc-switches"

What did you do?

I am attempting to compile a go package into webassembly. I had successfully followed the tutorial on the wiki page and applied the same steps to my particular use case. I was able to get a binary .wasm file. In order to do a quick check, I attempted to load the .wasm file into nodejs. When doing this, I get the following error:

(node:7918) UnhandledPromiseRejectionWarning: CompileError: WebAssembly.compile(): expected magic word 00 61 73 6d, found 21 3c 61 72 @+0

I compiled this this code into a .wasm file using GOOS=js GOARCH=wasm go build -o client.wasm. Then, I wrote a simply script to ensure that this was done correctly. The script is as follows:

import { readFileSync } from "fs";
async function createWebAssembly() {
   const buf = readFileSync("./client.wasm");
   const res = await WebAssembly.instantiate(new Uint8Array(buf).buffer);
}

createWebAssembly().then()

What did you expect to see?

Compiled program with warnings

What did you see instead?

See above error.