Alex Bradbury via llvm-dev
2021-Sep-06 17:40 UTC
[llvm-dev] LLVM Weekly - #401, September 6th 2021
LLVM Weekly - #401, September 6th 2021 ===================================== If you prefer, you can read a HTML version of this email at <http://llvmweekly.org/issue/401>. Welcome to the four hundred and first 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 Tanya Lattner provided a [summary of upcoming events](https://lists.llvm.org/pipermail/llvm-dev/2021-September/152483.html) within the LLVM community. JeanHeyd Meneide has summarised [recent progress on the ISO C23 standard](https://thephd.dev/c-the-improvements-june-september-virtual-c-meeting). MaskRay has blogged about [building glibc with LLD 13](https://maskray.me/blog/2021-09-05-build-glibc-with-lld). ## On the mailing lists * Sanjay Patel posted a [helpful summary of the intrinsic llvm::isnan discussion](https://lists.llvm.org/pipermail/llvm-dev/2021-September/152431.html), and Serge Pavlov has now [initiated a new thread to discuss the path forwards](https://lists.llvm.org/pipermail/llvm-dev/2021-September/152455.html). * Nikita Popov is [seeking input on opaque pointers and i8 GEPs](https://lists.llvm.org/pipermail/llvm-dev/2021-September/152486.html). "My proposal here is that in opaque pointers mode, LLVM should consider i8 GEPs canonical for GEPs with constant offsets. We should not attempt to 'guess' a good GEP type to use, and we should not try to generate complex GEP structures if a simple one will do. I don't think there's really any disadvantages to this, apart from the fact that it makes the discrepancy between typed and opaque pointer mode larger." * Evgueni Brevnov posted an RFC on [introducing a new call-site attribute](https://lists.llvm.org/pipermail/llvm-dev/2021-September/152429.html) to provide greater flexibility than a single per-translation unit code model. Philip Reames [proposed a slightly more generalised formulation](https://lists.llvm.org/pipermail/llvm-dev/2021-September/152448.html). * Luke Benes [asked if clang would follow GCC 11 in adopting a recent change to `-Wnonnull`](https://lists.llvm.org/pipermail/llvm-dev/2021-September/152437.html). * ORC JIT Weekly #38 [is out](https://lists.llvm.org/pipermail/llvm-dev/2021-September/152496.html), highlighting developments since early August. ## LLVM commits * A new tutorial was added on making your first change to LLVM. [3a6b722](https://reviews.llvm.org/rG3a6b722db856). * Setjmp/longjmp support was implemented for WebAssembly. [28780e5](https://reviews.llvm.org/rG28780e59f615). * Initial AArch64 JITLink support was committed. [2ed91da](https://reviews.llvm.org/rG2ed91da0f1f3). * CMake targets for code coverage reports were added. [2856719](https://reviews.llvm.org/rG2856719d74f0). * Support was added for a new LLVM-specific DWARF annotation. [89424a8](https://reviews.llvm.org/rG89424a829f3c). * The LLVM_ENABLE_RUNTIMES build option was documented. [d396d09](https://reviews.llvm.org/rGd396d09fc227). * A new -print-pipeline-pass option was added to opt. [c71869e](https://reviews.llvm.org/rGc71869ed4c24). * The deprecation of the legacy pass manager deprecation was documented. [2413d60](https://reviews.llvm.org/rG2413d6063b78). * The llvm.isnan patchset was reverted pending the conclusion of the RFC on llvm-dev. [3f1f08f](https://reviews.llvm.org/rG3f1f08f0ed6a). ## Clang commits * A `-canonical-prefixes` option was added. [3d157cf](https://reviews.llvm.org/rG3d157cfcc4ef). * Loop unrolling was added to the OpenMPIRBuilder. [650bbc5](https://reviews.llvm.org/rG650bbc56203c). ## Other project commits * The MLIR Cpp emitter was upstreamed. [2f0750d](https://reviews.llvm.org/rG2f0750dd2ec0). * An initial implementation of std::formatter was added to libcxx. [d7444d9](https://reviews.llvm.org/rGd7444d9f41e3). * LLDB gained a follow-fork-mode setting. [4a2a947](https://reviews.llvm.org/rG4a2a947317bf). * LLVM's libc gained a skeleton for the C standard condition variable functions. [2f4f452](https://reviews.llvm.org/rG2f4f452f166b). * The MLIR C/Python API was extended to allow for CFG construction. [8e6c55c](https://reviews.llvm.org/rG8e6c55c92c80).