diff options
Diffstat (limited to 'math/s_cacoshl.c')
| -rw-r--r-- | math/s_cacoshl.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/math/s_cacoshl.c b/math/s_cacoshl.c index dcdb1d5a64..3bcab1d277 100644 --- a/math/s_cacoshl.c +++ b/math/s_cacoshl.c @@ -1,5 +1,5 @@ /* Return arc hyperbole cosine for long double value. - Copyright (C) 1997, 1998, 2006, 2011 Free Software Foundation, Inc. + Copyright (C) 1997-2012 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. @@ -66,10 +66,14 @@ __cacoshl (__complex__ long double x) } /* The factor 16 is just a guess. */ else if (16.0L * fabsl (__imag__ x) < fabsl (__real__ x)) - /* Kahan's formula which avoid cancellation through subtraction in - some cases. */ - res = 2.0L * __clogl (__csqrtl ((x + 1.0L) / 2.0L) - + __csqrtl ((x - 1.0L) / 2.0L)); + { + /* Kahan's formula which avoid cancellation through subtraction in + some cases. */ + res = 2.0L * __clogl (__csqrtl ((x + 1.0L) / 2.0L) + + __csqrtl ((x - 1.0L) / 2.0L)); + if (signbit (__real__ res)) + __real__ res = 0.0L; + } else { __complex__ long double y; |