cpython

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History

Zachary Ware fda673d59f Issue #24974 : Force fp-model precice in mpdecimal.c on Windows As suggested by Steve Dower and approved by Stefan Krah.		2015-09-03 11:52:15 -05:00
..
libmpdec	Issue #24974 : Force fp-model precice in mpdecimal.c on Windows	2015-09-03 11:52:15 -05:00
tests	Closes #17202 : Merge with 3.4	2015-04-13 12:11:40 -05:00
_decimal.c	Removed redundant casts to `char *`.	2014-09-28 11:27:24 +03:00
docstrings.h	Use $type instead of $cls in the signature specification.	2014-05-02 14:34:11 +02:00
README.txt	Remove trailing whitespace.	2013-01-16 15:16:10 +01:00

README.txt


About
=====

_decimal.c is a wrapper for the libmpdec library. libmpdec is a fast C
library for correctly-rounded arbitrary precision decimal floating point
arithmetic. It is a complete implementation of Mike Cowlishaw/IBM's
General Decimal Arithmetic Specification.


Build process for the module
============================

As usual, the build process for _decimal.so is driven by setup.py in the top
level directory. setup.py autodetects the following build configurations:

   1) x64         - 64-bit Python, x86_64 processor (AMD, Intel)

   2) uint128     - 64-bit Python, compiler provides __uint128_t (gcc)

   3) ansi64      - 64-bit Python, ANSI C

   4) ppro        - 32-bit Python, x86 CPU, PentiumPro or later

   5) ansi32      - 32-bit Python, ANSI C

   6) ansi-legacy - 32-bit Python, compiler without uint64_t

   7) universal   - Mac OS only (multi-arch)


It is possible to override autodetection by exporting:

   PYTHON_DECIMAL_WITH_MACHINE=value, where value is one of the above options.


NOTE
====

decimal.so is not built from a static libmpdec.a since doing so led to
failures on AIX (user report) and Windows (mixing static and dynamic CRTs
causes locale problems and more).