mimic-cross

Fast cross-compiled environment requiring no special recipes.

Quick start

Usage

Just use this as base image and build image with --platform option.

FROM --platform=${BUILDPLATFORM} impactaky/mc-ubuntu22.04-${TARGETARCH}

Run example

Use binutils build example.

cd ./example
docker buildx build --platform=linux/arm64,linux/amd64 -f binutils.dockerfile .

This is the result on my local machine.

Base image	sec
ubuntu:22.04 (native compile)	29.9
ubuntu:22.04 (cross compile)	434.8
mc-ubuntu22.04 (cross compile)	34.6

How to introduce mimic-cross to existing image

Please write as following.

FROM --platform=${BUILDPLATFORM} impactaky/mc-ubuntu22.04-${TARGETARCH}-host AS mimic-host
FROM ubuntu:22.04
COPY --from=mimic-host / /mimic-cross
RUN /mimic-cross/mimic-cross.deno/setup.sh

Notes

mimic-cross currently does not support the apt command, please use apt-get.

mimic-cross currently does not support the pip command. Please use python3 -m pip instead.

Supported environments

• OS
  • ubuntu:22.04
• Build platform
  • linux/amd64
  • linux/arm64
• Target platform
  • linux/amd64
  • linux/arm64
• Package manager
  • apt-get
• Compiler
  • gcc-11
  • g++-11
• Language
  • python3.10

Supported packages can be found in supported.json

How to custom mimic-cross for your environment

See custom.md.

How to make runable users binary

T.B.D.

How mimic-cross works

Mimic-cross introduces binaries running on host into the environment run by qemu-use-static to speed up the process. To do so, the mimic-cross image has a sysroot for the host architecture under /mimic-cross.

This allows us to run the program faster without using QEMU instead of increasing the image size.
The image size increase can be handled by multistage build.

What happen when run package manager

1. Run in target sysroot
2. Check installed package
3. If supported package installed, package install in /mimic-cross sysroot.
4. Set up for mimicking (Patch to elf RUNPATH, etc...)

Environent variables

MIMIC_CROSS_DISABLE=1

When this value is set, execute only the original command by qemu and no special mimic-cross processing.

If you run the pip command with this, you will not be able to invoke the installed packages in the mimic-cross environment, but you can reduce the image size if you are simply installing dependencies needed for the build

MIMIC_CRSOS_DEBUG=1

When this variable is set, debugging information is output.

When reporting errors, please set this variable and attach the /var/log/mimic-cross.log.

MIIMC_CROSS_GCC_NATIVE_ARCH=xxx

Replace gcc/g++ -march=native option to -march=xxx

MIIMC_CROSS_GCC_NATIVE_CPU=xxx

Replace gcc/g++ -mcpu=native option to -march=xxx

MIIMC_CROSS_GCC_NATIVE_TUNE=xxx

Replace gcc/g++ -mtune=native option to -mtune=xxx