gcc/f/runtime/libF77/r_atn2.c

#include "f2c.h"

#ifdef KR_headers
double atan2();
double r_atn2(x,y) real *x, *y;
#else
#undef abs
#include <math.h>
double r_atn2(real *x, real *y)
#endif
{
return( atan2(*x,*y) );
}