1 /* Copyright (C) 2011-2022 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18 /*
19 * wrapper atan2(y,x)
20 */
21
22 #include <errno.h>
23 #include <math.h>
24 #include <math_private.h>
25 #include <math-svid-compat.h>
26 #include <libm-alias-double.h>
27
28
29 #if LIBM_SVID_COMPAT
30 double
__atan2(double y,double x)31 __atan2 (double y, double x)
32 {
33 double z;
34
35 if (__builtin_expect (x == 0.0 && y == 0.0, 0) && _LIB_VERSION == _SVID_)
36 return __kernel_standard (y, x, 3); /* atan2(+-0,+-0) */
37
38 z = __ieee754_atan2 (y, x);
39 if (__glibc_unlikely (z == 0.0 && y != 0.0 && isfinite (x)))
40 __set_errno (ERANGE);
41 return z;
42 }
43 libm_alias_double (__atan2, atan2)
44 #endif
45