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Ahead-of-Time compilation

class numba.pycc.CC(extension_name, source_module=None)

An object used to generate compiled extensions from Numba-compiled Python functions. extension_name is the name of the extension to be generated. source_module is the Python module containing the functions; if None, it is inferred by examining the call stack.

CC instances have the following attributes and methods:


(read-only attribute) The name of the extension module to be generated.


(read-write attribute) The directory the extension module will be written into. By default it is the directory the source_module is located in.


(read-write attribute) The name of the file the extension module will be written to. By default this follows the Python naming convention for the current platform.


(read-write attribute) The name of the CPU model to generate code for. This will select the appropriate instruction set extensions. By default, a generic CPU is selected in order to produce portable code.

Recognized names for this attribute depend on the current architecture and LLVM version. If you have LLVM installed, llc -mcpu=help will give you a list. Examples on x86-64 are "ivybridge", "haswell", "skylake" or "broadwell". You can also give the value "host" which will select the current host CPU.


(read-write attribute) If true, print out information while compiling the extension. False by default.

@export(exported_name, sig)

Mark the decorated function for compilation with the signature sig. The compiled function will be exposed as exported_name in the generated extension module.

All exported names within a given CC instance must be distinct, otherwise an exception is raised.


Compile all exported functions and generate the extension module as specified by output_dir and output_file.


Return a distutils.core.Extension instance allowing to integrate generation of the extension module in a conventional setup.py-driven build process. The optional kwargs let you pass optional parameters to the Extension constructor.

In this mode of operation, it is not necessary to call compile() yourself. Also, output_dir and output_file will be ignored.