diff options
Diffstat (limited to 'sysdeps/ieee754/dbl-64/s_lround.c')
| -rw-r--r-- | sysdeps/ieee754/dbl-64/s_lround.c | 41 |
1 files changed, 37 insertions, 4 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_lround.c b/sysdeps/ieee754/dbl-64/s_lround.c index bdc838a676..aa1275ddc3 100644 --- a/sysdeps/ieee754/dbl-64/s_lround.c +++ b/sysdeps/ieee754/dbl-64/s_lround.c @@ -1,5 +1,5 @@ /* Round double value to long int. - Copyright (C) 1997-2015 Free Software Foundation, Inc. + Copyright (C) 1997-2016 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. @@ -17,9 +17,12 @@ License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ +#include <fenv.h> +#include <limits.h> #include <math.h> #include <math_private.h> +#include <fix-fp-int-convert-overflow.h> long int @@ -60,13 +63,43 @@ __lround (double x) if (j0 == 20) result = (long int) i0; else - result = ((long int) i0 << (j0 - 20)) | (j >> (52 - j0)); + { + result = ((long int) i0 << (j0 - 20)) | (j >> (52 - j0)); +#ifdef FE_INVALID + if (sizeof (long int) == 4 + && sign == 1 + && result == LONG_MIN) + /* Rounding brought the value out of range. */ + feraiseexcept (FE_INVALID); +#endif + } } } else { - /* The number is too large. It is left implementation defined - what happens. */ + /* The number is too large. Unless it rounds to LONG_MIN, + FE_INVALID must be raised and the return value is + unspecified. */ +#ifdef FE_INVALID + if (FIX_DBL_LONG_CONVERT_OVERFLOW + && !(sign == -1 + && (sizeof (long int) == 4 + ? x > (double) LONG_MIN - 0.5 + : x >= (double) LONG_MIN))) + { + feraiseexcept (FE_INVALID); + return sign == 1 ? LONG_MAX : LONG_MIN; + } + else if (!FIX_DBL_LONG_CONVERT_OVERFLOW + && sizeof (long int) == 4 + && x <= (double) LONG_MIN - 0.5) + { + /* If truncation produces LONG_MIN, the cast will not raise + the exception, but may raise "inexact". */ + feraiseexcept (FE_INVALID); + return LONG_MIN; + } +#endif return (long int) x; } |