py/objfloat, py/modmath: Ensure M_PI and M_E defined.
In some compliation enviroments (e.g. mbed online compiler) with
strict standards compliance, <math.h> does not define constants such
as M_PI. Provide fallback definitions of M_E and M_PI where needed.
diff --git a/py/modmath.c b/py/modmath.c
index 6abf8ab..54262f6 100644
--- a/py/modmath.c
+++ b/py/modmath.c
@@ -31,6 +31,11 @@
#include <math.h>
+// M_PI is not part of the math.h standard and may not be defined
+#ifndef M_PI
+#define M_PI (3.14159265358979323846)
+#endif
+
/// \module math - mathematical functions
///
/// The `math` module provides some basic mathematical funtions for