diff options
Diffstat (limited to 'gnulib-m4/frexpl.m4')
| -rw-r--r-- | gnulib-m4/frexpl.m4 | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/gnulib-m4/frexpl.m4 b/gnulib-m4/frexpl.m4 new file mode 100644 index 00000000..c5da7446 --- /dev/null +++ b/gnulib-m4/frexpl.m4 @@ -0,0 +1,186 @@ +# frexpl.m4 serial 9 +dnl Copyright (C) 2007-2009 Free Software Foundation, Inc. +dnl This file is free software; the Free Software Foundation +dnl gives unlimited permission to copy and/or distribute it, +dnl with or without modifications, as long as this notice is preserved. + +AC_DEFUN([gl_FUNC_FREXPL], +[ + AC_REQUIRE([gl_MATH_H_DEFAULTS]) + FREXPL_LIBM= + AC_CACHE_CHECK([whether frexpl() can be used without linking with libm], + [gl_cv_func_frexpl_no_libm], + [ + AC_TRY_LINK([#include <math.h> + long double x;], + [int e; return frexpl (x, &e) > 0;], + [gl_cv_func_frexpl_no_libm=yes], + [gl_cv_func_frexpl_no_libm=no]) + ]) + if test $gl_cv_func_frexpl_no_libm = no; then + AC_CACHE_CHECK([whether frexpl() can be used with libm], + [gl_cv_func_frexpl_in_libm], + [ + save_LIBS="$LIBS" + LIBS="$LIBS -lm" + AC_TRY_LINK([#include <math.h> + long double x;], + [int e; return frexpl (x, &e) > 0;], + [gl_cv_func_frexpl_in_libm=yes], + [gl_cv_func_frexpl_in_libm=no]) + LIBS="$save_LIBS" + ]) + if test $gl_cv_func_frexpl_in_libm = yes; then + FREXPL_LIBM=-lm + fi + fi + if test $gl_cv_func_frexpl_no_libm = yes \ + || test $gl_cv_func_frexpl_in_libm = yes; then + save_LIBS="$LIBS" + LIBS="$LIBS $FREXPL_LIBM" + gl_FUNC_FREXPL_WORKS + LIBS="$save_LIBS" + case "$gl_cv_func_frexpl_works" in + *yes) gl_func_frexpl=yes ;; + *) gl_func_frexpl=no; REPLACE_FREXPL=1; FREXPL_LIBM= ;; + esac + else + gl_func_frexpl=no + fi + if test $gl_func_frexpl = yes; then + AC_DEFINE([HAVE_FREXPL], [1], + [Define if the frexpl() function is available.]) + dnl Also check whether it's declared. + dnl MacOS X 10.3 has frexpl() in libc but doesn't declare it in <math.h>. + AC_CHECK_DECL([frexpl], , [HAVE_DECL_FREXPL=0], [#include <math.h>]) + else + HAVE_DECL_FREXPL=0 + AC_LIBOBJ([frexpl]) + fi + AC_SUBST([FREXPL_LIBM]) +]) + +AC_DEFUN([gl_FUNC_FREXPL_NO_LIBM], +[ + AC_REQUIRE([gl_MATH_H_DEFAULTS]) + AC_CACHE_CHECK([whether frexpl() can be used without linking with libm], + [gl_cv_func_frexpl_no_libm], + [ + AC_TRY_LINK([#include <math.h> + long double x;], + [int e; return frexpl (x, &e) > 0;], + [gl_cv_func_frexpl_no_libm=yes], + [gl_cv_func_frexpl_no_libm=no]) + ]) + if test $gl_cv_func_frexpl_no_libm = yes; then + gl_FUNC_FREXPL_WORKS + case "$gl_cv_func_frexpl_works" in + *yes) gl_func_frexpl_no_libm=yes ;; + *) gl_func_frexpl_no_libm=no; REPLACE_FREXPL=1 ;; + esac + else + gl_func_frexpl_no_libm=no + dnl Set REPLACE_FREXPL here because the system may have frexpl in libm. + REPLACE_FREXPL=1 + fi + if test $gl_func_frexpl_no_libm = yes; then + AC_DEFINE([HAVE_FREXPL_IN_LIBC], [1], + [Define if the frexpl() function is available in libc.]) + dnl Also check whether it's declared. + dnl MacOS X 10.3 has frexpl() in libc but doesn't declare it in <math.h>. + AC_CHECK_DECL([frexpl], , [HAVE_DECL_FREXPL=0], [#include <math.h>]) + else + HAVE_DECL_FREXPL=0 + AC_LIBOBJ([frexpl]) + fi +]) + +dnl Test whether frexpl() works on finite numbers (this fails on +dnl MacOS X 10.4/PowerPC, on AIX 5.1, and on BeOS), on denormalized numbers +dnl (this fails on MacOS X 10.5/i386), and also on infinite numbers (this +dnl fails e.g. on IRIX 6.5 and mingw). +AC_DEFUN([gl_FUNC_FREXPL_WORKS], +[ + AC_REQUIRE([AC_PROG_CC]) + AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles + AC_CACHE_CHECK([whether frexpl works], [gl_cv_func_frexpl_works], + [ + AC_TRY_RUN([ +#include <float.h> +#include <math.h> +/* Override the values of <float.h>, like done in float.in.h. */ +#if defined __i386__ && (defined __BEOS__ || defined __OpenBSD__) +# undef LDBL_MIN_EXP +# define LDBL_MIN_EXP (-16381) +#endif +extern long double frexpl (long double, int *); +int main() +{ + volatile long double x; + /* Test on finite numbers that fails on AIX 5.1. */ + x = 16.0L; + { + int exp = -9999; + frexpl (x, &exp); + if (exp != 5) + return 1; + } + /* Test on finite numbers that fails on MacOS X 10.4, because its frexpl + function returns an invalid (incorrectly normalized) value: it returns + y = { 0x3fe028f5, 0xc28f5c28, 0x3c9eb851, 0xeb851eb8 } + but the correct result is + 0.505L = { 0x3fe028f5, 0xc28f5c29, 0xbc547ae1, 0x47ae1480 } */ + x = 1.01L; + { + int exp = -9999; + long double y = frexpl (x, &exp); + if (!(exp == 1 && y == 0.505L)) + return 1; + } + /* Test on large finite numbers. This fails on BeOS at i = 16322, while + LDBL_MAX_EXP = 16384. + In the loop end test, we test x against Infinity, rather than comparing + i with LDBL_MAX_EXP, because BeOS <float.h> has a wrong LDBL_MAX_EXP. */ + { + int i; + for (i = 1, x = 1.0L; x != x + x; i++, x *= 2.0L) + { + int exp = -9999; + frexpl (x, &exp); + if (exp != i) + return 1; + } + } + /* Test on denormalized numbers. */ + { + int i; + for (i = 1, x = 1.0L; i >= LDBL_MIN_EXP; i--, x *= 0.5L) + ; + if (x > 0.0L) + { + int exp; + long double y = frexpl (x, &exp); + /* On machines with IEEE854 arithmetic: x = 1.68105e-4932, + exp = -16382, y = 0.5. On MacOS X 10.5: exp = -16384, y = 0.5. */ + if (exp != LDBL_MIN_EXP - 1) + return 1; + } + } + /* Test on infinite numbers. */ + x = 1.0L / 0.0L; + { + int exp; + long double y = frexpl (x, &exp); + if (y != x) + return 1; + } + return 0; +}], [gl_cv_func_frexpl_works=yes], [gl_cv_func_frexpl_works=no], + [case "$host_os" in + aix* | beos* | darwin* | irix* | mingw* | pw*) + gl_cv_func_frexpl_works="guessing no";; + *) gl_cv_func_frexpl_works="guessing yes";; + esac + ]) + ]) +]) |