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v0.5.1
https://github.com/python/cpython
09 December 2020, 11:06:31 UTC
Revision 3fa19d7ff89be87139e2864fb9186b424d180a58 authored by Raymond Hettinger on 31 August 2004, 01:05:15 UTC, committed by Raymond Hettinger on 31 August 2004, 01:05:15 UTC 
Take advantage of the math library's ldexp for assembling a float by
 
components without division and without roundoff error for properly
sized mantissas (i.e. on systems with 53 or more mantissa bits per
float).  Eliminates the previous implementation's rounding bias as
aptly demonstrated by Tim Peters.
1 parent daec961
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Tip revision: 3fa19d7ff89be87139e2864fb9186b424d180a58 authored by Raymond Hettinger on 31 August 2004, 01:05:15 UTC
Take advantage of the math library's ldexp for assembling a float by
Tip revision: 3fa19d7
aclocal.m4 
# Code swiped wholesale from the GCC project, see
# http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12100

# This file can go away once autoconf 2.58 is out and being used -
# it's reported that this is fixed in the autoconf cvs already.

# AC_LANG_FUNC_LINK_TRY(C)(FUNCTION)
# ----------------------------------
# Don't include <ctype.h> because on OSF/1 3.0 it includes
# <sys/types.h> which includes <sys/select.h> which contains a
# prototype for select.  Similarly for bzero.
#
# A similar problem afflicts HP/UX, but it also hits <sys/time.h>
#
# This test used to merely assign f=$1 in main(), but that was
# optimized away by HP unbundled cc A.05.36 for ia64 under +O3,
# presumably on the basis that there's no need to do that store if the
# program is about to exit.  Conversely, the AIX linker optimizes an
# unused external declaration that initializes f=$1.  So this test
# program has both an external initialization of f, and a use of f in
# main that affects the exit status.
#
m4_define([AC_LANG_FUNC_LINK_TRY(C)],
[AC_LANG_PROGRAM(
[/* System header to define __stub macros and hopefully few prototypes,
    which can conflict with char $1 (); below.
    Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
    <limits.h> exists even on freestanding compilers.  Under hpux,
    including <limits.h> includes <sys/time.h> and causes problems
    checking for functions defined therein.  */
#if defined (__STDC__) && !defined (_HPUX_SOURCE)
# include <limits.h>
#else
# include <assert.h>
#endif
/* Override any gcc2 internal prototype to avoid an error.  */
#ifdef __cplusplus
extern "C"
{
#endif
/* We use char because int might match the return type of a gcc2
   builtin and then its argument prototype would still apply.  */
char $1 ();
/* The GNU C library defines this for functions which it implements
    to always fail with ENOSYS.  Some functions are actually named
    something starting with __ and the normal name is an alias.  */
#if defined (__stub_$1) || defined (__stub___$1)
choke me
#else
char (*f) () = $1;
#endif
#ifdef __cplusplus
}
#endif
], [return f != $1;])])
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