Build failing M_PI

[seemsindie]

Hello, i am getting this error when running make:

/home/ivan/Projects/Private/Craft/deps/glfw/examples/boing.c: In function ‘deg2rad’:
/home/ivan/Projects/Private/Craft/deps/glfw/examples/boing.c:129:28: error: ‘M_PI’ undeclared (first use in this function)
    return deg / 360 * (2 * M_PI);
                            ^

I am using arch linux, i have cmake, make, glfw, tried to install other deps...
Any idea why is failing?

[AlbertoLunaPe]

Same here, using Ubuntu 14.04 with all dependencies installed.

[etamme]

same here again - ubuntu 14.04

[fogleman]

Why don't one of you put this in an appropriate place and submit a pull request?

#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif

[etamme]

it looks like its a c99 thing, i think adding gcc -lm will fix it .. testing it now

[etamme]

yeah POSIX doesnt include M_PI, we need a #define _GNU_SOURCE added to the files that need M_PI. I'll see if i can get a PR together

[fogleman]

I see this in the GLFW files that use M_PI, probably an appropriate place to add another...

#if defined(_MSC_VER)
 // Make MS math.h define M_PI
 #define _USE_MATH_DEFINES
#endif

[etamme]

yeah im basically changing that to
#if defined(_MSC_VER) // Make MS math.h define M_PI #define _USE_MATH_DEFINES #elif __GNUC__ #define _GNU_SOURCE #endif

edit: ...sorry i cant get github to format the code properly with linebreaks