Mercurial > gnulib
view tests/test-printf-frexp.c @ 17363:5a51fb7777a9
sys_select, sys_time: port 2013-01-30 Solaris 2.6 fix to Cygwin
Problem reported by Marco Atzeri in
<http://lists.gnu.org/archive/html/bug-gnulib/2013-03/msg00000.html>.
* lib/sys_select.in.h [HAVE_SYS_SELECT_H && _CYGWIN_SYS_TIME_H]:
Simply delegate to the system <sys/select.h> in this case too.
Also, pay attention to _GL_SYS_SELECT_H_REDIRECT_FROM_SYS_TIME_H only
if OSF/1, since otherwise Cygwin breaks, and it doesn't seem to
be needed on Solaris either.
* lib/sys_time.in.h [_CYGWIN_SYS_TIME_H]:
Simply delgate to the system <sys/time.h> in this case.
author | Paul Eggert <eggert@cs.ucla.edu> |
---|---|
date | Tue, 19 Mar 2013 09:08:47 -0700 |
parents | e542fd46ad6f |
children | 344018b6e5d7 |
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/* Test of splitting a double into fraction and mantissa. Copyright (C) 2007-2013 Free Software Foundation, Inc. This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ /* Written by Bruno Haible <bruno@clisp.org>, 2007. */ #include <config.h> #include "printf-frexp.h" #include <float.h> #include "macros.h" static double my_ldexp (double x, int d) { for (; d > 0; d--) x *= 2.0; for (; d < 0; d++) x *= 0.5; return x; } int main () { int i; /* The use of 'volatile' guarantees that excess precision bits are dropped when dealing with denormalized numbers. It is necessary on x86 systems where double-floats are not IEEE compliant by default, to avoid that the results become platform and compiler option dependent. 'volatile' is a portable alternative to gcc's -ffloat-store option. */ volatile double x; for (i = 1, x = 1.0; i <= DBL_MAX_EXP; i++, x *= 2.0) { int exp = -9999; double mantissa = printf_frexp (x, &exp); ASSERT (exp == i - 1); ASSERT (mantissa == 1.0); } for (i = 1, x = 1.0; i >= DBL_MIN_EXP; i--, x *= 0.5) { int exp = -9999; double mantissa = printf_frexp (x, &exp); ASSERT (exp == i - 1); ASSERT (mantissa == 1.0); } for (; i >= DBL_MIN_EXP - 100 && x > 0.0; i--, x *= 0.5) { int exp = -9999; double mantissa = printf_frexp (x, &exp); ASSERT (exp == DBL_MIN_EXP - 1); ASSERT (mantissa == my_ldexp (1.0, i - DBL_MIN_EXP)); } for (i = 1, x = 1.01; i <= DBL_MAX_EXP; i++, x *= 2.0) { int exp = -9999; double mantissa = printf_frexp (x, &exp); ASSERT (exp == i - 1); ASSERT (mantissa == 1.01); } for (i = 1, x = 1.01; i >= DBL_MIN_EXP; i--, x *= 0.5) { int exp = -9999; double mantissa = printf_frexp (x, &exp); ASSERT (exp == i - 1); ASSERT (mantissa == 1.01); } for (; i >= DBL_MIN_EXP - 100 && x > 0.0; i--, x *= 0.5) { int exp = -9999; double mantissa = printf_frexp (x, &exp); ASSERT (exp == DBL_MIN_EXP - 1); ASSERT (mantissa >= my_ldexp (1.0, i - DBL_MIN_EXP)); ASSERT (mantissa <= my_ldexp (2.0, i - DBL_MIN_EXP)); ASSERT (mantissa == my_ldexp (x, - exp)); } for (i = 1, x = 1.73205; i <= DBL_MAX_EXP; i++, x *= 2.0) { int exp = -9999; double mantissa = printf_frexp (x, &exp); ASSERT (exp == i - 1); ASSERT (mantissa == 1.73205); } for (i = 1, x = 1.73205; i >= DBL_MIN_EXP; i--, x *= 0.5) { int exp = -9999; double mantissa = printf_frexp (x, &exp); ASSERT (exp == i - 1); ASSERT (mantissa == 1.73205); } for (; i >= DBL_MIN_EXP - 100 && x > 0.0; i--, x *= 0.5) { int exp = -9999; double mantissa = printf_frexp (x, &exp); ASSERT (exp == DBL_MIN_EXP - 1); ASSERT (mantissa >= my_ldexp (1.0, i - DBL_MIN_EXP)); ASSERT (mantissa <= my_ldexp (2.0, i - DBL_MIN_EXP)); ASSERT (mantissa == my_ldexp (x, - exp)); } return 0; }