[llvm-dev] LLVM Weekly - #295, August 26th 2019

[Alex Bradbury via llvm-dev]

LLVM Weekly - #295, August 26th 2019
====================================

If you prefer, you can read a HTML version of this email at
<http://llvmweekly.org/issue/295>.

Welcome to the two hundred and ninety-fifth 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

Kristóf Umann has written up a [final report on his GSoC
project](https://szelethus.github.io/gsoc2019/) to enhance bug reports in the
Clang Static Analyzer.


## On the mailing lists

* Alex Davies started a thread on [using GlobalISel to provide peephole
optimisations](http://lists.llvm.org/pipermail/llvm-dev/2019-August/134700.html).

* Jonas Devlieghere [suggested removing the unfinished ncurses UI from
LLDB](http://lists.llvm.org/pipermail/lldb-dev/2019-August/015420.html). So
far, respondents are in favour of keeping it.

* Prashanth N. R. writes to the LLVM mailing list [about FC, a new LLVM-based
Fortran
frontend](http://lists.llvm.org/pipermail/llvm-dev/2019-August/134620.html).
"The performance in SPEC becnhmarks are comparable(better in few cases) to
flang and gfortran compilers in both speed and rate runs."

* Hans Wennborg has sent out a [reminder to write 9.0 release
notes](http://lists.llvm.org/pipermail/llvm-dev/2019-August/134699.html).

* Neil Nelson [shared a chart of memory usage for
test-release.sh](http://lists.llvm.org/pipermail/llvm-dev/2019-August/134691.html).

* Gábor Horváth gave an [update on ading lifetime analysis to
Clang](http://lists.llvm.org/pipermail/cfe-dev/2019-August/063164.html).

* Pavel Labath [shared an RFC on support for unwinding in LLDB for
Windows](http://lists.llvm.org/pipermail/lldb-dev/2019-August/015417.html).

* DeForest Richards kicked off a discussion on [re-organizing the LLVM
docs](http://lists.llvm.org/pipermail/llvm-dev/2019-August/134682.html).

* Johannes Doerfert [started an RFC thread on increasing the scope of
Value::getPointerXXX
methods](http://lists.llvm.org/pipermail/llvm-dev/2019-August/134680.html).


## LLVM commits

* Documentation was added for GWP-ASan, a sampled allocator aiming to help
finding use-after-free and heap-buffer-overflow bugs.
[r369552](https://reviews.llvm.org/rL369552).

* A "must-be-executed-context" explorer was committed, allowing the traversal
of instructions that are guaranteed to be executed whenever instruction I is.
[r369765](https://reviews.llvm.org/rL369765).

* `-x86-experimental-vector-widening-legalization` was added to allow the
previous behaviour to be selectively enabled.
[r369332](https://reviews.llvm.org/rL369332).

* Initial GlobalISel infrastructure for RISC-V was added.
[r369467](https://reviews.llvm.org/rL369467).


## Clang commits

* The StaticAnalyzer VirtualCallChecker was improved, and parts of it are now
enabled by default. [r369449](https://reviews.llvm.org/rL369449).

* The clangd features table was updated with links to relevant LSP extension
proposals. [r369229](https://reviews.llvm.org/rL369229).


## Other project commits

* The LLVM test-suite has started to gain microbenchmarks for memory functions
(e.g. memcmp, memcpy, ...). [r369707](https://reviews.llvm.org/rL369707).

* LLD gained further improvements to Android dynamic relocation packing.
[r369488](https://reviews.llvm.org/rL369488).

* LLDB now supports the C++20 `char8_t` type.
[r369582](https://reviews.llvm.org/rL369582).