Can't build from Dockerfile on Docker 20.10.4 on Raspberry Pi

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Bug Report

Docker 20.10.4 appropriately reads the manifest of an image, which for the balenalib/armv7hf-alpine:latest erroneously reports linux/amd64 as its architecture. Thus attempting to manually run the build process for this repo/Dockerfile (while waiting for #2) results in the following warnings and final build problem:

docker-compose build flic-daemon
WARNING: Some networks were defined but are not used by any service: traefik_backend
Building flic-daemon
Step 1/16 : ARG ARCH_NAME=rpi
Step 2/16 : FROM balenalib/${ARCH_NAME}-alpine:latest
latest: Pulling from balenalib/armv7hf-alpine
f55b840e27d3: Already exists
402fc73d1261: Pull complete
1b87b7489741: Pull complete
ed14ceb62157: Pull complete
006276fa4414: Pull complete
7979890402ea: Pull complete
408933703be8: Pull complete
09604c85eac2: Pull complete
87d51f119897: Pull complete
Digest: sha256:b468ab88785f856d585c627c199b43663a40454c24947f23e6dd1319679c5823
Status: Downloaded newer image for balenalib/armv7hf-alpine:latest
 ---> f1fdb4e04d5e
Step 3/16 : ARG ARCH_NAME
 ---> [Warning] The requested image's platform (linux/amd64) does not match the detected host platform (linux/arm/v7) and no specific platform was requested
 ---> Running in 761dd4a5ddd3
Removing intermediate container 761dd4a5ddd3
 ---> a4b5d8046b2f
Step 4/16 : ARG BUILD_DATE=1970-01-01T00:00:00Z
 ---> [Warning] The requested image's platform (linux/amd64) does not match the detected host platform (linux/arm/v7) and no specific platform was requested
 ---> Running in b6735fc48836
Removing intermediate container b6735fc48836
 ---> b40d0bb2f872
Step 5/16 : ARG FLICLIB_ARCH=unknown

 ---> [Warning] The requested image's platform (linux/amd64) does not match the detected host platform (linux/arm/v7) and no specific platform was requested
 ---> Running in 183a1037a433
Removing intermediate container 183a1037a433
 ---> 20ec2d11c6ba
Step 6/16 : ARG FLICLIB_VERSION=0.5
 ---> [Warning] The requested image's platform (linux/amd64) does not match the detected host platform (linux/arm/v7) and no specific platform was requested
 ---> Running in 68db5f68999d
Removing intermediate container 68db5f68999d
 ---> 60b36343d703
Step 7/16 : ARG VCS_REF=0000000
 ---> [Warning] The requested image's platform (linux/amd64) does not match the detected host platform (linux/arm/v7) and no specific platform was requested
 ---> Running in 34ca51ed1dba
Removing intermediate container 34ca51ed1dba
 ---> 17176c999e3f
Step 8/16 : ARG VERSION=0.5.3
 ---> [Warning] The requested image's platform (linux/amd64) does not match the detected host platform (linux/arm/v7) and no specific platform was requested
 ---> Running in 79f55acf6688
Removing intermediate container 79f55acf6688
 ---> 5f92850f5e54
Step 9/16 : LABEL org.label-schema.build-date=${BUILD_DATE}       org.label-schema.description="Flic smart button bridge for single-board computers."       org.label-schema.docker.cmd="docker run --detach --restart=unless-stopped --net=host --cap-add=NET_ADMIN --name=flic renemarc/balena-flic"       org.label-schema.docker.cmd.debug="docker run -it --net=host --cap-add=NET_ADMIN flic bash"       org.label-schema.docker.cmd.help="docker run -it --rm --net=host --cap-add=NET_ADMIN renemarc/balena-flic flicd --help"       org.label-schema.name="balena Flic"       org.label-schema.url="https://flic.io/"       org.label-schema.vcs-ref=${VCS_REF}       org.label-schema.vcs-url="https://github.com/renemarc/balena-flic"       org.label-schema.version=${VERSION}       org.label-schema.schema-version="1.0"
 ---> [Warning] The requested image's platform (linux/amd64) does not match the detected host platform (linux/arm/v7) and no specific platform was requested
 ---> Running in 89d95b9c6188
Removing intermediate container 89d95b9c6188
 ---> a9c10af95fbb
Step 10/16 : RUN ["cross-build-start"]
 ---> [Warning] The requested image's platform (linux/amd64) does not match the detected host platform (linux/arm/v7) and no specific platform was requested
 ---> Running in 2a502e412cd5
standard_init_linux.go:219: exec user process caused: exec format error
ERROR: Service 'flic-daemon' failed to build: The command 'cross-build-start' returned a non-zero code: 1

Steps to Reproduce (unless obvious)

1. Create docker-compose.yml with build statements:

   container_name: flic-daemon
   image: flic-daemon
   build:
     context: https://github.com/renemarc/balena-flic.git
     dockerfile: Dockerfile
     args:
       ARCH_NAME: armv7hf
   restart: unless-stopped
   network_mode: host
   cap_add:
     - NET_ADMIN
   

2. Attempt a build: docker-compose build flic-daemon, get the above error messages

Environment Info

Raspberry Pi 4 running Raspberry Pi OS 32 bit and Docker 20.10.04

Suggested fix

More pressure on Balena to correct their image manifests so that they can run on the intended architecture.