Re: [Libmesh-users] undefined M_PI

[Stogner, R. H <roy...@ic...>]

On Wed, 11 Dec 2019, Povolotskyi, Mykhailo wrote:

> I have encountered a problem with M_PI symbol:

M_PI is defined by any Unix98-standard math.h

https://pubs.opengroup.org/onlinepubs/009695399/basedefs/math.h.html

But if you're not using a Unix98 math.h you might have a problem?

There's a workaround for MSVC which nanoflann.hpp already uses but
which is kind of fragile, for instance:
https://stackoverflow.com/questions/6563810/m-pi-works-with-math-h-but-not-with-cmath-in-visual-studio

And if you're using yet-another non-Unix98 math.h still then you might
need a different workaround or there might be no workaround other than
defining M_PI (and any other missing symbols, of which there hopefully
aren't too too many) yourself.
---
Roy