commit f415aae96554cf83379fdd7fd4c9152822f9b977 · pyrox.dev/nixpkgs

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doc/using/overlays.chapter.md
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           The Nixpkgs attribute is `openblas` for ILP64 (integer width = 64 bits) and `openblasCompat` for LP64 (integer width = 32 bits).  `openblasCompat` is the default.

     

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       -   [LAPACK reference](http://www.netlib.org/lapack/) (also provides BLAS)

     

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       -   [LAPACK reference](http://www.netlib.org/lapack/) (also provides BLAS and CBLAS)

     

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           The Nixpkgs attribute is `lapack-reference`.

     

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       Intel MKL requires an `openmp` implementation when running with multiple processors. By default, `mkl` will use Intel's `iomp` implementation if no other is specified, but this is a runtime-only dependency and binary compatible with the LLVM implementation. To use that one instead, Intel recommends users set it with `LD_PRELOAD`. Note that `mkl` is only available on `x86_64-linux` and `x86_64-darwin`. Moreover, Hydra is not building and distributing pre-compiled binaries using it.

     

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       For BLAS/LAPACK switching to work correctly, all packages must depend on `blas` or `lapack`. This ensures that only one BLAS/LAPACK library is used at one time. There are two versions of BLAS/LAPACK currently in the wild, `LP64` (integer size = 32 bits) and `ILP64` (integer size = 64 bits). Some software needs special flags or patches to work with `ILP64`. You can check if `ILP64` is used in Nixpkgs with `blas.isILP64` and `lapack.isILP64`. Some software does NOT work with `ILP64`, and derivations need to specify an assertion to prevent this. You can prevent `ILP64` from being used with the following:

     

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       To override `blas` and `lapack` with its reference implementations (i.e. for development purposes), one can use the following overlay:

     

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       ```nix

     

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       self: super:

     

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       {

     

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         blas = super.blas.override {

     

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           blasProvider = self.lapack-reference;

     

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         };

     

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         lapack = super.lapack.override {

     

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           lapackProvider = self.lapack-reference;

     

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         };

     

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       }

     

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       ```

     

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       For BLAS/LAPACK switching to work correctly, all packages must depend on `blas` or `lapack`. This ensures that only one BLAS/LAPACK library is used at one time. There are two versions of BLAS/LAPACK currently in the wild, `LP64` (integer size = 32 bits) and `ILP64` (integer size = 64 bits). The attributes `blas` and `lapack` are `LP64` by default. Their `ILP64` version are provided through the attributes `blas-ilp64` and `lapack-ilp64`. Some software needs special flags or patches to work with `ILP64`. You can check if `ILP64` is used in Nixpkgs with `blas.isILP64` and `lapack.isILP64`. Some software does NOT work with `ILP64`, and derivations need to specify an assertion to prevent this. You can prevent `ILP64` from being used with the following:

     

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       ```nix

     

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       { stdenv, blas, lapack, ... }: