5261 libm should stop using synonyms.h
5298 fabs is 0-sized, confuses dis(1) and others
Reviewed by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
Approved by: Gordon Ross <gwr@nexenta.com>

          --- old/usr/src/lib/libm/common/C/atan2pi.c
          +++ new/usr/src/lib/libm/common/C/atan2pi.c

   1    1  /*
   2    2   * CDDL HEADER START
   3    3   *
   4    4   * The contents of this file are subject to the terms of the
   5    5   * Common Development and Distribution License (the "License").
   6    6   * You may not use this file except in compliance with the License.
   7    7   *
   8    8   * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9    9   * or http://www.opensolaris.org/os/licensing.
  10   10   * See the License for the specific language governing permissions
  11   11   * and limitations under the License.
  12   12   *
  13   13   * When distributing Covered Code, include this CDDL HEADER in each
  14   14   * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15   15   * If applicable, add the following below this CDDL HEADER, with the
  16   16   * fields enclosed by brackets "[]" replaced with your own identifying
  17   17   * information: Portions Copyright [yyyy] [name of copyright owner]
  18   18   *

  19   19   * CDDL HEADER END
  20   20   */
  21   21  /*
  22   22   * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  23   23   */
  24   24  /*
  25   25   * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  26   26   * Use is subject to license terms.
  27   27   */
  28   28  
  29      -#pragma weak atan2pi = __atan2pi
  30      -
  31   29  /*
  32   30   * atan2pi(x) = atan2(x)/pi
  33   31   */
  34   32  
  35   33  #include "libm.h"
  36   34  
  37   35  static const double invpi = 0.3183098861837906715377675;
  38   36  
  39   37  double
  40   38  atan2pi(double y, double x) {

  41   39          int     ix, iy;
  42   40  
  43   41          if (x == 0.0 && y == 0.0) {
  44   42                  ix = ((int *)&x)[HIWORD];
  45   43                  iy = ((int *)&y)[HIWORD];
  46   44                  if (ix >= 0)
  47   45                          return (y);
  48   46                  return ((iy >= 0)? 1.0 : -1.0);
  49   47          }
  50   48          return (atan2(y, x) * invpi);
  51   49  }

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