2020-02-29 retire in-tree GPL dtc

[emaste]

Summary

Now that we no longer have GCC 4.2.1 in the tree and can assume FreeBSD is being built with a C++11 compiler available we can use BSDL dtc unconditionally and retire the GPL dtc.

GPL dtc now has FreeBSD CI support via Cirrus-CI to help ensure it continues to build/work on FreeBSD and is available in the ports tree if needed.

[kevans]

powerpc* was the last reason to keep GPL dtc in-tree, IMO.

[theraven]

Unless I'm missing something, this leaves GPL'd dtc's sources in the tree but removes the ability to build them. Would it make sense to remove the code at the same time as removing the build system goo?

The build system changes look fine to me.

[emaste]

I intend to rm the sources at the same time but will probably do it as a separate commit. Do need to ensure we don't remove libfdt though.

[kevans]

In D23192#508363, @emaste wrote:

I intend to rm the sources at the same time but will probably do it as a separate commit. Do need to ensure we don't remove libfdt though.

Both kernel and loader build that out of the distinct and more up-to-date ^/sys/contrib/libfdt, so nothing should be dependent on the version there.

[emaste]

Ok, removal of contrib/gcclibs, contrib/gcc, and contrib/dtc will be staged in my deorbit-gcc branch https://github.com/emaste/freebsd/tree/deorbit-gcc

[imp]

usr.bin/Makefile

215 ↗

(On Diff #66783)

Do we still need c++11 check?

[emaste]

usr.bin/Makefile

215 ↗

(On Diff #66783)

No. I was thinking of doing a separate pass to remove both setting it in ${COMPILER_FEATURES} and all of the checks.

[imp]

usr.bin/Makefile

215 ↗

(On Diff #66783)

Fair point

[emaste]

• rebase
• add UPDATING