v4.8.20

Changes

• CI: Cannot set --env CUDA_VISIBLE_DEVICES for docker run when using ng --gpus "device=${CUDA_VISIBLE_DEVICES:-all}" - dropping --env arg. @ggorman (#2710)
• misc: switch to f-string throughout @mloubout (#2706)
• misc: Remove make-pbs.py @FabioLuporini (#2700)
• compiler: Hotfix the memory estimate for certain devices @EdCaunt (#2699)
• misc: Expand derivative touchup @JDBetteridge (#2695)
• misc: Remove decrepit folders @EdCaunt (#2663)
• misc: Switch mpi-x pub to ieee link @georgebisbas (#2688)

API

• dsl: Add an additional Border convenience class for boundary conditions @EdCaunt (#2646)
• compiler: Add a utility to estimate memory usage for an operator @EdCaunt (#2659)
• dsl: Expand derivative @JDBetteridge (#2559)
• misc: Add custom warnings functionality @JDBetteridge (#2692)
• api: fix custom coeffs with cross derivatives @mloubout (#2672)

Examples

• examples: Fix density handling in acoustic @mloubout (#2716)
• Clean notebook metadata @JDBetteridge (#2639)

Documentation

• docs: fix mmin/mmax docstring @mloubout (#2703)
• Clean notebook metadata @JDBetteridge (#2639)

Compiler

• compiler: prevent directions from non indexed @mloubout (#2704)
• compiler: Avoid generating parentheses when not needed @FabioLuporini (#2689)
• compiler: Pass the whole descriptor to buf_reuse cbk @FabioLuporini (#2687)
• compiler: Reapply "Cache Scope + Dependence instances" @enwask (#2677)
• compiler: Cache Scope + Dependence instances @enwask (#2669)
• compiler: fix conditional reductions @mloubout (#2671)
• compiler: fix temp/array alloc @mloubout (#2664)
• mpi: fix allreduce iteration space @mloubout (#2662)
• compiler: Lazy IET visitors + Search @enwask (#2621)
• compiler: add top description to generated file @mloubout (#2652)

MPI

• mpi: Prevent errors with single rank @mloubout (#2698)
• compiler: Fixup MPI over Arrays + arguments overriding @FabioLuporini (#2697)
• data: prevent mpi comm with single rank @mloubout (#2685)
• mpi: fix multi conditional for allreduce @mloubout (#2673)
• mpi: fix in-loop allreduce with multiple reductions @mloubout (#2668)
• mpi: fix allreduce iteration space @mloubout (#2662)

Architectures and JIT

• arch: prevent shell string escape in codepy cmdline strings @mloubout (#2715)

🐛 Bug Fixes

• compiler: Hotfix estimate memory again @EdCaunt (#2707)
• compiler: prevent directions from non indexed @mloubout (#2704)
• compiler: Fixup MPI over Arrays + arguments overriding @FabioLuporini (#2697)
• compiler: Fixup nbytes-avail-mapper @FabioLuporini (#2654)
• compiler: Call set_device in pthreads @FabioLuporini (#2679)
• compiler: Add buf-reuse opt-option and rcompile caching @FabioLuporini (#2674)
• compiler: Fix HaloTouch hashing @FabioLuporini (#2676)
• Revert "compiler: Cache Scope + Dependence instances" @mloubout (#2675)
• mpi: fix multi conditional for allreduce @mloubout (#2673)
• compiler: Fix Bundle.symbolic_shape @FabioLuporini (#2665)
• compiler: Patch IterationSpace.intersection @FabioLuporini (#2647)
• compiler: Patch merge and reduction HaloScheme passes @FabioLuporini (#2645)

Continuous Integration

• compiler: improve rcompile @mloubout (#2719)
• Remove dangling layers. @ggorman (#2686)
• ci: Set CONTAINER_NAME within a step. @ggorman (#2684)
• ci: isolate GPU runners, respect CUDA_VISIBLE_DEVICES, drop global prunes @ggorman (#2680)

Installation

• pip prod(deps): update matplotlib requirement from <3.10.6 to <3.10.7 @dependabot[bot] (#2722)
• pip prod(deps): update cupy-cuda12x requirement from <13.5.2 to <13.6.1 @dependabot[bot] (#2720)
• gh(deps): bump actions/checkout from 4 to 5 @dependabot[bot] (#2709)
• pip prod(deps): update dask-cuda requirement from <25.6.1 to <25.8.1 @dependabot[bot] (#2705)
• install: Remove files and directories not needed for install @JDBetteridge (#2702)
• pip prod(deps): update matplotlib requirement from <3.10.4 to <3.10.6 @dependabot[bot] (#2694)
• pip prod(deps): bump pyrevolve from 2.2.5 to 2.2.6 @dependabot[bot] (#2678)
• pip prod(deps): update distributed requirement from <2025.5.2 to <2025.7.1 @dependabot[bot] (#2666)
• pip prod(deps): update fsspec requirement from <2025.5.2 to <2025.7.1 @dependabot[bot] (#2670)
• pip prod(deps): update cupy-cuda12x requirement from <13.4.2 to <13.5.2 @dependabot[bot] (#2661)
• pip prod(deps): update mpi4py requirement from <4.0.4 to <4.1.1 @dependabot[bot] (#2649)
• deps: Bump upper NumPy version to 2.3.1 @EdCaunt (#2653)
• pip prod(deps): update cgen requirement from <2021,>=2020.1 to >=2020.1,<2026 @dependabot[bot] (#2642)
• pip prod(deps): update pillow requirement from <11.2.2,>11 to >11,<11.3.1 @dependabot[bot] (#2651)
• pip prod(deps): bump pyrevolve from 2.2.4 to 2.2.5 @dependabot[bot] (#2650)
• pip prod(deps): update distributed requirement from <2025.4.2 to <2025.5.2 @dependabot[bot] (#2641)
• pip prod(deps): update scipy requirement from <1.15.3 to <1.15.4 @dependabot[bot] (#2648)
• pip prod(deps): update dask-cuda requirement from <25.4.1 to <25.6.1 @dependabot[bot] (#2644)
• pip prod(deps): update matplotlib requirement from <3.10.2 to <3.10.4 @dependabot[bot] (#2640)

Full Changelog: v4.8.19...v4.8.20