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-rw-r--r--m4/frexpl.m4231
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diff --git a/m4/frexpl.m4 b/m4/frexpl.m4
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+# frexpl.m4 serial 20
+dnl Copyright (C) 2007-2016 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])
+ AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
+
+ dnl Persuade glibc <math.h> to declare frexpl().
+ AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+
+ dnl Check whether it's declared.
+ dnl Mac OS 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>]])
+
+ FREXPL_LIBM=
+ if test $HAVE_DECL_FREXPL = 1; then
+ gl_CHECK_FREXPL_NO_LIBM
+ 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="$LIBS -lm"
+ AC_LINK_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <math.h>
+ long double x;]],
+ [[int e; return frexpl (x, &e) > 0;]])],
+ [gl_cv_func_frexpl_in_libm=yes],
+ [gl_cv_func_frexpl_in_libm=no])
+ LIBS="$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 ;;
+ 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.])
+ fi
+ fi
+ if test $HAVE_DECL_FREXPL = 0 || test $gl_func_frexpl = no; then
+ dnl Find libraries needed to link lib/frexpl.c.
+ if test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1; then
+ AC_REQUIRE([gl_FUNC_FREXP])
+ FREXPL_LIBM="$FREXP_LIBM"
+ else
+ FREXPL_LIBM=
+ fi
+ fi
+ AC_SUBST([FREXPL_LIBM])
+])
+
+AC_DEFUN([gl_FUNC_FREXPL_NO_LIBM],
+[
+ AC_REQUIRE([gl_MATH_H_DEFAULTS])
+ AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
+ dnl Check whether it's declared.
+ dnl Mac OS 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>]])
+ if test $HAVE_DECL_FREXPL = 1; then
+ gl_CHECK_FREXPL_NO_LIBM
+ 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.])
+ fi
+ fi
+])
+
+dnl Test whether frexpl() can be used without linking with libm.
+dnl Set gl_cv_func_frexpl_no_libm to 'yes' or 'no' accordingly.
+AC_DEFUN([gl_CHECK_FREXPL_NO_LIBM],
+[
+ AC_CACHE_CHECK([whether frexpl() can be used without linking with libm],
+ [gl_cv_func_frexpl_no_libm],
+ [
+ AC_LINK_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#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])
+ ])
+])
+
+dnl Test whether frexpl() works on finite numbers (this fails on
+dnl Mac OS X 10.4/PowerPC, on AIX 5.1, and on BeOS), on denormalized numbers
+dnl (this fails on Mac OS 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_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+#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
+#if defined __i386__ && defined __FreeBSD__
+# undef LDBL_MIN_EXP
+# define LDBL_MIN_EXP (-16381)
+#endif
+#if (defined _ARCH_PPC || defined _POWER) && defined _AIX && (LDBL_MANT_DIG == 106) && defined __GNUC__
+# undef LDBL_MIN_EXP
+# define LDBL_MIN_EXP DBL_MIN_EXP
+#endif
+#if defined __sgi && (LDBL_MANT_DIG >= 106)
+# if defined __GNUC__
+# undef LDBL_MIN_EXP
+# define LDBL_MIN_EXP DBL_MIN_EXP
+# endif
+#endif
+extern
+#ifdef __cplusplus
+"C"
+#endif
+long double frexpl (long double, int *);
+int main()
+{
+ int result = 0;
+ 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)
+ result |= 1;
+ }
+ /* Test on finite numbers that fails on Mac OS 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))
+ result |= 2;
+ }
+ /* 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)
+ {
+ result |= 4;
+ break;
+ }
+ }
+ }
+ /* 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 Mac OS X 10.5: exp = -16384, y = 0.5. */
+ if (exp != LDBL_MIN_EXP - 1)
+ result |= 8;
+ }
+ }
+ /* Test on infinite numbers. */
+ x = 1.0L / 0.0L;
+ {
+ int exp;
+ long double y = frexpl (x, &exp);
+ if (y != x)
+ result |= 16;
+ }
+ return result;
+}]])],
+ [gl_cv_func_frexpl_works=yes],
+ [gl_cv_func_frexpl_works=no],
+ [
+changequote(,)dnl
+ case "$host_os" in
+ aix | aix[3-6]* | beos* | darwin* | irix* | mingw* | pw*)
+ gl_cv_func_frexpl_works="guessing no";;
+ *) gl_cv_func_frexpl_works="guessing yes";;
+ esac
+changequote([,])dnl
+ ])
+ ])
+])