dev-lang/rust includes bundled llvm-4.0.1 (presumably with patches). I understand that support for system-llvm was dropped, but the bundled version is configured using: "-DLLVM_TARGETS_TO_BUILD=X86;ARM;AArch64;Mips;PowerPC;SystemZ;JSBackend;MSP430;Sparc;NVPTX;Hexagon" I don't know how those targets were selected, but I'm pretty sure that it won't need most of those targets on my machine.
(In reply to Jan Vesely from comment #0) done in pg_overlay
*** Bug 638584 has been marked as a duplicate of this bug. ***
Fixed in dev-lang/rust-1.26.0. The ebuild now uses LLVM_TARGETS to decide what targets to build.
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=71eba02631d5129e1e4c2729f4234727d7bac498 commit 71eba02631d5129e1e4c2729f4234727d7bac498 Author: Dirkjan Ochtman <djc@gentoo.org> AuthorDate: 2018-05-14 13:37:00 +0000 Commit: Dirkjan Ochtman <djc@gentoo.org> CommitDate: 2018-05-14 14:38:35 +0000 dev-lang/rust: version bump to 1.26.0 Use LLVM_TARGETS to decide which targets to build for bundled LLVM. Use xz-compressed tarballs where possible to limit bandwidth/storage. Fixes: https://bugs.gentoo.org/627288 Fixes: https://bugs.gentoo.org/655600 Package-Manager: Portage-2.3.24, Repoman-2.3.6 dev-lang/rust/Manifest | 4 + dev-lang/rust/rust-1.26.0.ebuild | 181 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 185 insertions(+)