Julia v1.9 Release Notes
========================

New language features
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Language changes
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Compiler/Runtime improvements
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Command-line option changes
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* In Linux and Windows, `--threads=auto` now tries to infer usable number of CPUs from the
  process affinity which is set typically in HPC and cloud environments ([#42340]).

Multi-threading changes
-----------------------


Build system changes
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New library functions
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New library features
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Standard library changes
------------------------

#### Package Manager

#### LinearAlgebra

* We are now wholly reliant on libblastrampoline (LBT) for calling
  BLAS and LAPACK. OpenBLAS is shipped by default, but building the
  system image with other BLAS/LAPACK libraries is not
  supported. Instead, it is recommended that the LBT mechanism be used
  for swapping BLAS/LAPACK with vendor provided ones. ([#44360])

#### Markdown

#### Printf

#### Random

#### REPL

#### SparseArrays

#### Dates

#### Downloads

#### Statistics

#### Sockets

#### Tar

#### Distributed

* The package environment (active project, `LOAD_PATH`, `DEPOT_PATH`) are now propagated
  when adding *local* workers (e.g. with `addprocs(N::Int)` or through the `--procs=N`
  command line flag) ([#43270]).
* `addprocs` for local workers now accept the `env` keyword argument for passing
  environment variables to the workers processes. This was already supported for
  remote workers ([#43270]).

#### UUIDs

#### Mmap

#### DelimitedFiles


Deprecated or removed
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External dependencies
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Tooling Improvements
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