• ExternalGCC

FreeBSD stopped including modern versions of GCC and binutils in the base system; the project focused initially on bringing the excellent LLVM-based toolchain (especially, clang and lld), but there were also licensing motivations. However, being so recent, some platforms are not supported by LLVM and some users may wish to use a GNU toolchain even on platforms where there is support for LLVM. The purpose of this page is to document the steps required to facilitate the use of a modern GNU toolchain tracking both a "global" TODO list as well as a per-platform checklist of needed steps. One of the goals of this process is to deprecate and remove the old GCC 4.2.1 and binutils 2.17.50 in the base system.

Toolchain Packages

The external GNU toolchain consists of two packages: binutils and GCC. These packages are provided in two different ways.

External Toolchain

First a set of "external toolchain" packages are provided which can be used to cross-build (or natively build) a FreeBSD base system. These packages are built by the devel/binutils and devel/freebsd-gcc[69] ports. Each of these ports has a "flavor" for each supported architecture. These build packages named <arch>-binutils and <arch>-gcc[69]. The GCC package includes a suitable CROSS_TOOLCHAIN Makefile and depends on the appropriate binutils package. These packages install cross-build binaries under /usr/local and can be used like so:

# pkg install amd64-gcc6
# cd /path/to/src
# make CROSS_TOOLCHAIN=amd64-gcc6 buildworld

Native Toolchain

The second set of packages are used to build a native toolchain for a given architecture that provides a system toolchain (e.g. /usr/bin/cc and /usr/bin/ld) via the base/binutils and base/gcc6 ports. These packages can either be built natively or as cross-built packages using CROSS_TOOLCHAIN and CROSS_SYSROOT. The steps to cross-build a native toolchain consist of:

• Install the appropriate external toolchain packages on a build host.
• Build a world using this external toolchain via CROSS_TOOLCHAIN.
• Install this world to a suitable location via DESTDIR. This installed location will then be used as the CROSS_SYSROOT when cross-building packages.
• Install native packages on the build host for build dependencies of binutils and gcc.
• Build the base/binutils and base/gcc6 packages using CROSS_TOOLCHAIN and CROSS_SYSROOT. In addition, you will want to cross-build pkg itself so that the packages be installed on a target host.

For example:

# pkg install mips-gcc6
# cd /usr/src
# make CROSS_TOOLCHAIN=mips-gcc6 TARGET_ARCH=mips buildworld
# mkdir /usr/mips/sysroot
# make CROSS_TOOLCHAIN=mips-gcc6 TARGET_ARCH=mips installworld DESTDIR=/usr/mips/sysroot
# pkg install math/gmp math/mpfr bison gmake gettext-tools
# mkdir /usr/mips/packages
# cd /usr/ports/ports-mgmt/pkg
# make CROSS_TOOLCHAIN=mips-gcc6 CROSS_SYSROOT=/usr/mips/sysroot package
# cp work/pkg/* /usr/mips/packages
# cd ../../base/binutils
# make CROSS_TOOLCHAIN=mips-gcc6 CROSS_SYSROOT=/usr/mips/sysroot package
# cp work/pkg/* /usr/mips/packages
# cd ../../base/gcc6
# make CROSS_TOOLCHAIN=mips-gcc6 CROSS_SYSROOT=/usr/mips/sysroot package
# cp work/pkg/* /usr/mips/packages

This would result in /usr/mips/packages containing three packages: pkg, freebsd-binutils, and freebsd-gcc6. These can be used to seed an initial package repository (in case no packages are currently provided for this architecture) such that an installed target system can use 'pkg install freebsd-binutils' and 'pkg install freebsd-gcc6'.

(There is more information about which packages are currently being provided for which architecture.)

TODO List

This is a list of general MI todo items.

Per-architecture Checklist

This table contains a set of steps required by each architecture to support an external GNU toolchain.

Legend

(1) This is not required for external toolchain but is required for removing src/contrib/gcc.

See Also

ExternalToolchain

CategoryHowTo