Also provide binaries for Android ARM

[thunder-coding]

Closes #1556

[evanw]

I am unable to run this on my computer. I get this:

$ make GOOS=android GOARCH=arm NPMDIR=npm/esbuild-android-arm platform-unixlike
test -n "android" && test -n "arm" && test -n "npm/esbuild-android-arm"
mkdir -p "npm/esbuild-android-arm/bin"
cd "npm/esbuild-android-arm" && npm version "0.12.25" --allow-same-version
v0.12.25
CGO_ENABLED=0 GOOS="android" GOARCH="arm" go build "-ldflags=-s -w" -trimpath -o "npm/esbuild-android-arm/bin/esbuild" ./cmd/esbuild
# github.com/evanw/esbuild/cmd/esbuild
loadinternal: cannot find runtime/cgo
/usr/local/go/pkg/tool/darwin_amd64/link: running clang failed: exit status 1
ld: warning: option -s is obsolete and being ignored
ld: unknown option: -z
clang: error: linker command failed with exit code 1 (use -v to see invocation)

make: *** [platform-unixlike] Error 2

This is on macOS 11.5.1. I don't understand why cgo is apparently enabled despite CGO_ENABLED=0. Here is a reduced reproduction:

$ cat main.go 
package main

import "runtime/debug"

func main() {
	debug.SetGCPercent(-1)
}

$ CGO_ENABLED=0 GOOS="android" GOARCH="arm" go build main.go
# command-line-arguments
loadinternal: cannot find runtime/cgo
/usr/local/go/pkg/tool/darwin_amd64/link: running clang failed: exit status 1
ld: unknown option: -z
clang: error: linker command failed with exit code 1 (use -v to see invocation)

This appears to be a bug in Go.

Edit: I have filed this bug as golang/go#48246.

[thunder-coding]

Did you try compiling with older Golang versions?

Don't know why but I feel it's somehow related to wrong dynamic linker path when cross compiling issue (not mentioning the issue here since it may be unrelated)

[evanw]

The Go team said that "internal linking" is unsupported with Android ARM and building this requires a C toolchain to build. Maybe this means I need to build this on a 32-bit Android ARM device?

Are you able to build esbuild using this command? If so, what OS version, CPU architecture, and Go version are you on?

[thunder-coding]

I was able to build on Android ARM 7.0 using on Termux using

go build ./cmd/esbuild

The Golang version I had was the latest in official Termux repository as of writing this comment.

go version output

go version go1.16.7 android/arm

and I have a esbuild binary.

And about cross compiling, you need to get the C compiler from Android SDK.

If you need some example on how to do it see termux/termux-packages

Under scripts/build/termux_step_setup_toolchain.sh, you can see how it's setting up CC, CXX and other environment variables (along with some other changes which might not be needed here)

[evanw]

I'm closing this as I don't want to complicate esbuild's deploy process by having to install the entire Android build toolchain for this one platform. All of the other 18 platforms I already support can be built fine by Go on any platform without installing anything. I still don't understand why Go doesn't support cross-platform builds for this platform in particular (Go and Android are even both Google projects!) but that's up to them I guess. If you want to run esbuild on 32-bit Android ARM, you'll have to build it yourself. Sorry.