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The Stan Math Library is a C++ template library for automatic differentiation of any order using forward, reverse, and mixed modes. It includes a range of built-in functions for probabilistic modeling, linear algebra, and equation solving.
https://mc-stan.org
BSD 3-Clause "New" or "Revised" License
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Does BIT=32 do anything? #3043

Closed WardBrian closed 2 months ago

WardBrian commented 2 months ago

Description

The CmdStan installation docs and Math Library Developer docs both mention the make variable BIT=32 as possibly being required on Windows for 32-bit builds.

I can't find anywhere this is used in the makefiles or in the source. Do we actually still support 32-bit systems? What does this flag actually change?

WardBrian commented 2 months ago

Yikes, looks like it hasn't done anything since 2018! https://github.com/stan-dev/math/pull/956 changed the CXXFLAGS from setting -m$(BIT) to just detecting the arch and setting the flag directly (a much better thing to do, in the end!)