mkl-sys

Auto-generated bindings to Intel MKL. Currently only supports Linux and Windows, and not considered stable/ready for production use. Only tested with Intel MKL 2019 and 2020.

This crate relies on Intel MKL having been installed on the target system, and that the environment is set up for use with MKL. The easiest way to make it work is to run the provided mklvars.sh setup script that is bundled with MKL. This sets up the environment for use with MKL. This crate then detects the correct Intel MKL installation by inspecting the value of the MKLROOT environment variable.

Note that we used to support pkg-config, but as of Intel MKL 2020, Intel is shipping broken configurations. Therefore we instead directly rely on the value of MKLROOT.

Windows support

Compile time requirements

To compiled this create on Windows, the following requirements have to be met:

To run bindgen a Clang (libclang) installation is required. According to the bindgen documentation version 3.9 should suffice. A recent pre-built version of Clang can be downloaded on the LLVM release page. To ensure that bindgen can find Clang, the environment variable LIBCLANG_PATH used by bindgen has to be set to point to the bin folder of the Clang installation.
On Windows, Clang uses the MSVC standard library. Therefore, the build process should be started from a Visual Studio or Build Tools command prompt. The command prompt can be started from a start menu shortcut created by the Visual Studio installer or by running a vcvars script (e.g. C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars64.bat) in an open command prompt. An IDE such as Clion with a configured MSVC toolchain should already provide this configuration for targets inside of the IDE.
The environment variable MKLROOT has to be configured properly to point to the path containing the bin, lib, include, etc. folders of MKL (e.g. C:\Program Files (x86)\IntelSWTools\compilers_and_libraries\windows\mkl). This can also be done by running the mklvars.bat script in the bin folder of MKL.

A script to build the library and run all tests on Windows might then look like this:

call "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars64.bat"
call "C:\Program Files (x86)\IntelSWTools\compilers_and_libraries\windows\mkl\bin\mklvars.bat intel64"
set LIBCLANG_PATH=C:\Program Files\LLVM\bin
cargo test --release --features "all"

Run time requirements

During runtime the corresponding redistributable DLLs of MKL (e.g. located in C:\Program Files (x86)\IntelSWTools\compilers_and_libraries\windows\redist\intel64_win\mkl) have to be in PATH.

Known issues

bindgen does not seem to be able to properly handle many preprocessor macros, such as e.g. dss_create. This appears to be related to this issue.
Generating bindings for the entire MKL library might take a lot of time. To circumvent this, you should use features to enable binding generation only for the parts of the library that you will need. For example, the dss feature generates bindings for the Direct Sparse Solver (DSS) interface.

A second approach that alleviates long build times due to bindgen is to use the following profile override in your application's TOML file:

[profile.dev.package.bindgen]
opt-level = 2

This ensures that bindgen is compiled with optimizations on, significantly improving its runtime when invoked by the build script in mkl-sys.

License

Intel MKL is provided by Intel and licensed separately.