[llvm-dev] LLVM Weekly - #309, December 2nd 2019

[Alex Bradbury via llvm-dev]

LLVM Weekly - #309, December 2nd 2019
=====================================

If you prefer, you can read a HTML version of this email at
<http://llvmweekly.org/issue/309>.

Welcome to the three hundred and ninth issue of LLVM Weekly, a weekly
newsletter (published every Monday) covering developments in LLVM, Clang, and
related projects. LLVM Weekly is brought to you by [Alex
Bradbury](https://www.linkedin.com/in/alex-bradbury/). Subscribe to future
issues at <http://llvmweekly.org> and pass it on to anyone else you think may
be interested. Please send any tips or feedback to <asb at asbradbury.org>, or
@llvmweekly or @asbradbury on Twitter.


## News and articles from around the web

Further videos from the LLVM Developers' Meeting
[continue to be posted on
YouTube](https://www.youtube.com/channel/UCv2_41bSAa5Y_8BacJUZfjQ/videos).


## On the mailing lists

* Oliver Stannard has posted an RFC with a prototype patch for [displaying
source variable locations in
llvm-objdump](http://lists.llvm.org/pipermail/llvm-dev/2019-November/137221.html).
The functionality is
[demonstrated through demo output](https://reviews.llvm.org/M2). All
respondents so far are very positive about this improvement.

* Christian Kühnel reports that [pre-merge checks are ready for beta
testing](http://lists.llvm.org/pipermail/llvm-dev/2019-November/137195.html).
As explained in
[the documentation](https://github.com/google/llvm-premerge-checks/blob/master/docs/user_doc.md),
this provides the ability to apply and test patches from Phabricator prior to
committing.

* Brian Gesiak is seeking [advice on porting coro-split pass to the new pass
manager](http://lists.llvm.org/pipermail/llvm-dev/2019-November/137203.html).
This is an SCC (strongly connected components) pass, so slightly more involved
than porting the coroutine passes implemented as function passes.

* Galina Kistanova shares that [a subset of buildbots will report build status
to GitHub
now](http://lists.llvm.org/pipermail/llvm-dev/2019-November/137198.html).

* Nuno Lopes started a discussion on the [semantics for shufflevector with an
undef
mask](http://lists.llvm.org/pipermail/llvm-dev/2019-November/137242.html),
arguing that the LangRef semantics are incorrect.

* Arthur Peters is [looking for reviewers for a set of clang-c API and Python
cindex
patches](http://lists.llvm.org/pipermail/cfe-dev/2019-November/064017.html).


## LLVM commits

* The ORCv2 lookup API was updated to support weak references and to better
support static archives. [674df13](https://reviews.llvm.org/rG674df13b5fa).

* Floating point conversion intrinsics were implemented for SVE.
[4a649ad](https://reviews.llvm.org/rG4a649ad21aa).

* Various issues were fixed with the expansion of Mips sc/scs/ll/lld
instructions. [11074bf](https://reviews.llvm.org/rG11074bfffee).


## Clang commits

* The implicit conversion sanitizer can now sanitize pre/post
increment/decrement of types with a bit width smaller than `int`.
[9872ea4](https://reviews.llvm.org/rG9872ea4ed1d).

* clangd now implements cross-file rename.
[852bafa](https://reviews.llvm.org/rG852bafae2bb).


## Other project commits

* The zlib compression level used by LLD will now vary depending on the
optimisation level (e.g. `-O1` etc.).
[19edd67](https://reviews.llvm.org/rG19edd675c63).

* sanitizer-common was updated to build with glibc 2.31, which had some ABI
changes on many architectures.
[947f969](https://reviews.llvm.org/rG947f9692440).