Bug#876200: llvm-toolchain-4.0: Please backport upstream r299910 to fix FTBFS for rustc 1.19.0 on ppc64el

[Ximin Luo]

Package: llvm-toolchain-4.0
Version: 1:4.0.1-5
Severity: important
Tags: patch

Dear Maintainer,

rustc 1.19 FTBFS on ppc64el with this version 1:4.0.1-5:
https://buildd.debian.org/status/fetch.php?pkg=rustc&arch=ppc64el&ver=1.19.0%2Bdfsg3-2&stamp=1505822614&raw=0
"Invalid PPC CTR loop!"

For some reason this did not happen with 1:4.0.1-3 but I can reproduce it on plummer with 1:4.0.1-5.

Luckily, upstream has already committed a fix:

https://bugs.llvm.org//show_bug.cgi?id=32485
https://reviews.llvm.org/rL299910
Raw diff: https://reviews.llvm.org/D31790?download=true

I tested it on top of 1:4.0.1-5 and it works well to fix the above rustc build failure.

X

-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'unstable-debug'), (500, 'testing-debug'), (500, 'buildd-unstable'), (300, 'unstable'), (100, 'experimental'), (1, 'experimental-debug')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.12.0-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_GB.utf8, LC_CTYPE=en_GB.utf8 (charmap=UTF-8), LANGUAGE=en_GB:en (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)