Basement

This basement project is a collection of useful recipes that can be included by other projects. Most importantly it provides pre-made classes to handle common build systems and other recurring tasks. Additionally a sandbox and common GCC toolchains are ready-to-use.

Prerequisites

• A x86_64 system with the regular development tools installed
  • gcc >= 5.x
  • bash
  • POSIX awk (GNU awk version >= 3.1.5)
  • GNU m4
  • GNU make >= 3.80
  • perl >= 5.6.1
  • GNU tar
  • gzip
  • bzip2
  • rsync
  • xz-utils
• Bob Build Tool (https://github.com/BobBuildTool/bob)

How to build

Actually there isn't much to build directly in this repository. Head over to one of the examples to see how this repository is used:

• Embedded systems
• Linux containers

In tests/linux there are a couple of recipes that build small test packages which use the basement layer. They act as smoke tests for this project.

How to use

First you need to add the basement layer to your project. To do so add a layers entry to config.yaml:

bobMinimumVersion: "0.15"
layers:
    - basement

and then add this repository as submodule to your project:

$ git submodule add https://github.com/BobBuildTool/basement.git layers/basement

To use all facilities of the basement project you just need to inherit the basement::rootrecipe class in your root recipe:

inherit: [ "basement::rootrecipe" ]

This will make your recipe a root recipe and already setup the sandbox with a proper host toolchain. See the next chapter what tools and toolchains are readily available.

Provided tools and C/C++ toolchains

The following tools can be used by naming them in {checkout,build,package}Tools:

• bison
• cpio
• flex
• make
• pkg-config
• squashfs-tools
• e2fsprogs
• util-linux

The following cross compiling toolchains are available pre-configured. If you need other targets you can depend on devel::cross-toolchain directly and configure it as you like.

• devel::cross-toolchain-aarch64-linux-gnu: ARMv8-A AArch64 Linux with glibc.
• devel::cross-toolchain-aarch64-none-elf: ARMv8-A/R AArch64 bare metal toolchain with newlib libc.
• devel::cross-toolchain-arm-linux-gnueabihf: ARMv7-A Linux with glibc. Hard floating point ABI.
• devel::cross-toolchain-arm-none-eabi: ARMv7 bare metal toolchain with newlib libc.
• devel::cross-toolchain-x86_64-linux-gnu: x86_64 toolchain for Linux with glibc.

To use a cross compiling toolchain include it where needed via:

depends:
    - name: <recipe name here>
      use: [tools, environment]
      forward: True

Regarding the C/C++ toolchains the following tools are defined and used in the recipes:

• target-toolchain: This is the main toolchain. Every C/C++ package uses it. It represents the compiler that builds for the target system where the package should run in the end. Usually, but not necessarily, this is a cross compiler even on the same architecture.

  In autotools speak this is the compiler for the --host= system.

• host-toolchain: This toolchain represents the native host machine compiler. Even though it builds host executables, it does never fingerprint the results. Instead, it is intended to be used in the buildScript if the package also needs the host compiler during build time where none of the host build object code is part of the result. Points to the host gcc or the gcc of the sandbox. Only selected packages need it when being built in the sandbox.

  In autotools speak this is the compiler of the --build= system.

• host-compat-toolchain: A toolchain that builds portable host executables that should be able to run on the oldest supported Ubuntu LTS. Even though it builds for the host architecture, it is a cross compiler with a backwards compatible glibc version. When using the basement::rootrecipe class, this is the default target-toolchain. It is defined as a dedicated name to be able to compile specifically for the host when needed:

  depends:
    - ...
    - name: some::package
      tools:
        target-toolchain: host-compat-toolchain
  

  This will build some::package for the host regardless of the currently defined target toolchain.

• host-native-toolchain: This toolchain represents the native host machine compiler. In contrast to host-toolchain it does fingerprint the system. Used if a package needs to be compiled natively and the object code is part of the package result.