lang/rust: add powerpc64 ELFv2 support

[mikael]

Summary

https://lists.freebsd.org/pipermail/freebsd-ppc/2019-June/010632.html
https://wiki.freebsd.org/powerpc/llvm-elfv2

http://mikael.urankar.free.fr/FreeBSD/rust/1.38.0/cargo-0.39.0-powerpc64-unknown-freebsd-ELFv2.tar.gz
http://mikael.urankar.free.fr/FreeBSD/rust/1.38.0/rust-std-1.38.0-powerpc64-unknown-freebsd-ELFv2.tar.gz
http://mikael.urankar.free.fr/FreeBSD/rust/1.38.0/rustc-1.38.0-powerpc64-unknown-freebsd-ELFv2.tar.gz

needs https://reviews.freebsd.org/D22039

[jbeich]

lang/rust/Makefile

150

Did you mean > and not >=? If so 1300036 users may end up using Clang but not ELFv2.

155

None of rustc --print target-list currently have OS version. Did you check ports depending on lang/rust build fine?

[jbeich]

lang/rust/Makefile

155

Nevermind. I didn't notice this target is for LLVM.

[mikael]

need to fix osversion, distinfo, Uses/cargo.mk

lang/rust/Makefile

150

yes, it should be >=

155

I tried devel/bingrep, it works fine.

[mikael]

I did a

svn mv patch-src_librustc__llvm_build.rs extra-patch-ppc64-gcc

but it doesn't translate well in the diff, what is the correct way to do it?

[tobik]

lang/rust/Makefile

58–68

Please just use -${PPC_ABI:tl} and revert the distinfo changes. The bootstrap tarball filenames are all lowercase. Let's keep it that way.

95

EXTRA_PATCHES+=

149–155

It sure feels like this (and extra-patch-ppc64-gcc) should be some cfg! or env! thing in Rust rather than us wrangling with conditional patches, but not sure how that would work exactly. It's fine for now I guess.

304–306

Best add PPC_ABI=ELFv1 here so that makesum can still work as it should on every arch.

309–310

Replace BOOTSTRAPS_SUFFIX with PPC_ABI=ELFv2.

310–311

Revert these too.

[mikael]

address comments

[tobik]

• Rebase on rP516995