```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>
```

 Split Close Expand all Collapse all
```          --- old/usr/src/lib/libm/common/C/atanh.c
+++ new/usr/src/lib/libm/common/C/atanh.c
```
 ↓ open down ↓ 19 lines elided ↑ open up ↑
```  20   20   */
21   21
22   22  /*
24   24   */
25   25  /*
27   27   * Use is subject to license terms.
28   28   */
29   29
30      -#pragma weak atanh = __atanh
30 +#pragma weak __atanh = atanh
31   31
32   32  /* INDENT OFF */
33   33  /*
34   34   * atanh(x)
35   35   * Code originated from 4.3bsd.
36   36   * Modified by K.C. Ng for SUN 4.0 libm.
37   37   * Method :
38   38   *                  1              2x                          x
39   39   *      atanh(x) = --- * log(1 + -------) = 0.5 * log1p(2 * --------)
40   40   *                  2             1 - x                      1 - x
```
 ↓ open down ↓ 3 lines elided ↑ open up ↑
```  44   44   *                    2              1 - |x|
45   45   *
46   46   * Special cases:
47   47   *      atanh(x) is NaN if |x| > 1 with signal;
48   48   *      atanh(NaN) is that NaN with no signal;
49   49   *      atanh(+-1) is +-INF with signal.
50   50   */
51   51  /* INDENT ON */
52   52
53   53  #include "libm.h"
54      -#include "libm_synonyms.h"
55   54  #include "libm_protos.h"
56   55  #include <math.h>
57   56
58   57  double
59   58  atanh(double x) {
60   59          double t;
61   60
62   61          if (isnan(x))
63   62                  return (x * x);         /* switched from x + x for Cheetah */
64   63          t = fabs(x);
65   64          if (t > 1.0)
66   65                  return (_SVID_libm_err(x, x, 30));      /* sNaN */
67   66          if (t == 1.0)
68   67                  return (_SVID_libm_err(x, x, 31));      /* x/0; */
69   68          t = t / (1.0 - t);
70   69          return (copysign(0.5, x) * log1p(t + t));
71   70  }
```
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