Rearranged and added comments to object.h, to clarify many things that have taken me "too long" to reverse-engineer over the years. Vastly reduced the nesting level and redundancy of #ifdef-ery. Took a light stab at repairing comments that are no longer true. sys_gettotalrefcount(): Changed to enable under Py_REF_DEBUG. It was enabled under Py_TRACE_REFS, which was much heavier than necessary. sys.gettotalrefcount() is now available in a Py_REF_DEBUG-only build.

/* Portable fmod(x, y) implementation for systems that don't have it */

#include "pyconfig.h"

#include "pyport.h"
#include <errno.h>

double
fmod(double x, double y)
{
	double i, f;
	
	if (y == 0.0) {
		errno = EDOM;
		return 0.0;
	}
	
	/* return f such that x = i*y + f for some integer i
	   such that |f| < |y| and f has the same sign as x */
	
	i = floor(x/y);
	f = x - i*y;
	if ((x < 0.0) != (y < 0.0))
		f = f-y;
	return f;
}