In file included from src/estimate_noise_spectrum.c:29:
src/extra_functions.c:44:9: warning: 'M_PI' macro redefined [-Wmacro-redefined]
#define M_PI 3.14159265358979323846f
^
/usr/include/math.h:149:9: note: previous definition is here
#define M_PI 3.14159265358979323846 /* pi */
^
Getting this on FreeBSD 11.1: