Kaniko doesnt support Variant label for images

[PhoenixMage]

Actual behavior
When using kaniko on an armv7 instance kaniko seems to use the armhf architecture.
If I use docker build then armv7 is correctly used.

Expected behavior
Kaniko should use the armv7 architecture.

To Reproduce
/kaniko/executor -f Dockerfile --no-push
gives armhf
docker build
gives armv7

Additional Information

• Dockerfile

FROM alpine:3.11
RUN apk update --print-arch

Description	Yes/No
Please check if this a new feature you are proposing
Please check if the build works in docker but not in kaniko	- [Yes ]
Please check if this error is seen when you use --cache flag
Please check if your dockerfile is a multistage dockerfile

[PhoenixMage]

Seems runtime.GOARM doesnt exist, goarm is a private symbol which you can access using "unsafe"

My thoughts were to set a symbol at compile time using the linker but I lack the skills to implement that.

[tejal29]

We did merge a #980 which prefers platform you are currently running on.
I tried adding Variant to goarm, however i got this error

import (
  _ "unsafe"
)

var (
	goarm uint8
)
func currentPlatform() v1.Platform {
	return v1.Platform{
		OS:           runtime.GOOS,
		Architecture: runtime.GOARCH,
+		Variant: string(goarm),
	}
}

However, i got this error so not sure if adding the Variant is the right way.

/ # /kaniko/executor -f dockerfiles/Dockerfile_test1 --context=dir:///workspace --destination=gcr.io/tejal-test/test --tarPath=image.tar
INFO[0000] Resolved base name ubuntu:latest to ubuntu:latest 
INFO[0000] Using dockerignore file: /workspace/.dockerignore 
INFO[0000] Resolved base name ubuntu:latest to ubuntu:latest 
INFO[0000] Retrieving image manifest ubuntu:latest      
ERRO[0001] Error while retrieving image from cache: ubuntu:latest no child with platform amd64/linux in index index.docker.io/library/ubuntu:latest 
INFO[0001] Retrieving image manifest ubuntu:latest      
error building image: no child with platform amd64/linux in index index.docker.io/library/ubuntu:latest

[tejal29]

Forgot to mention,
I modified the Makefile to retrieve GOARM from the current platform i am building on.
However it is empty

tejaldesai@@kaniko (507)$ make && docker cp /usr/local/google/home/tejaldesai/workspace/kaniko/out/executor c765d295c9cb:/kaniko
GOARCH=amd64 GOARM= GOOS=linux CGO_ENABLED=0 go build -ldflags '-extldflags "-static" -X github.com/GoogleContainerTools/kaniko/pkg/version.version=v0.16.0 -w -s  ' -o out/executor github.com/GoogleContainerTools/kaniko/cmd/executor
tejaldesai@@kaniko (507)$