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-rw-r--r--gnulib-m4/frexp.m4112
1 files changed, 43 insertions, 69 deletions
diff --git a/gnulib-m4/frexp.m4 b/gnulib-m4/frexp.m4
index 04f4067..3a450f6 100644
--- a/gnulib-m4/frexp.m4
+++ b/gnulib-m4/frexp.m4
@@ -1,5 +1,5 @@
-# frexp.m4 serial 15
-dnl Copyright (C) 2007-2015 Free Software Foundation, Inc.
+# frexp.m4 serial 7
+dnl Copyright (C) 2007, 2008, 2009, 2010 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.
@@ -7,19 +7,25 @@ dnl with or without modifications, as long as this notice is preserved.
AC_DEFUN([gl_FUNC_FREXP],
[
AC_REQUIRE([gl_MATH_H_DEFAULTS])
- AC_REQUIRE([gl_CHECK_FREXP_NO_LIBM])
FREXP_LIBM=
+ AC_CACHE_CHECK([whether frexp() can be used without linking with libm],
+ [gl_cv_func_frexp_no_libm],
+ [
+ AC_TRY_LINK([#include <math.h>
+ double x;],
+ [int e; return frexp (x, &e) > 0;],
+ [gl_cv_func_frexp_no_libm=yes],
+ [gl_cv_func_frexp_no_libm=no])
+ ])
if test $gl_cv_func_frexp_no_libm = no; then
AC_CACHE_CHECK([whether frexp() can be used with libm],
[gl_cv_func_frexp_in_libm],
[
save_LIBS="$LIBS"
LIBS="$LIBS -lm"
- AC_LINK_IFELSE(
- [AC_LANG_PROGRAM(
- [[#include <math.h>
- double x;]],
- [[int e; return frexp (x, &e) > 0;]])],
+ AC_TRY_LINK([#include <math.h>
+ double x;],
+ [int e; return frexp (x, &e) > 0;],
[gl_cv_func_frexp_in_libm=yes],
[gl_cv_func_frexp_in_libm=no])
LIBS="$save_LIBS"
@@ -44,6 +50,8 @@ AC_DEFUN([gl_FUNC_FREXP],
if test $gl_func_frexp = yes; then
AC_DEFINE([HAVE_FREXP], [1],
[Define if the frexp() function is available and works.])
+ else
+ AC_LIBOBJ([frexp])
fi
AC_SUBST([FREXP_LIBM])
])
@@ -51,7 +59,15 @@ AC_DEFUN([gl_FUNC_FREXP],
AC_DEFUN([gl_FUNC_FREXP_NO_LIBM],
[
AC_REQUIRE([gl_MATH_H_DEFAULTS])
- AC_REQUIRE([gl_CHECK_FREXP_NO_LIBM])
+ AC_CACHE_CHECK([whether frexp() can be used without linking with libm],
+ [gl_cv_func_frexp_no_libm],
+ [
+ AC_TRY_LINK([#include <math.h>
+ double x;],
+ [int e; return frexp (x, &e) > 0;],
+ [gl_cv_func_frexp_no_libm=yes],
+ [gl_cv_func_frexp_no_libm=no])
+ ])
if test $gl_cv_func_frexp_no_libm = yes; then
gl_FUNC_FREXP_WORKS
case "$gl_cv_func_frexp_works" in
@@ -66,71 +82,31 @@ AC_DEFUN([gl_FUNC_FREXP_NO_LIBM],
if test $gl_func_frexp_no_libm = yes; then
AC_DEFINE([HAVE_FREXP_IN_LIBC], [1],
[Define if the frexp() function is available in libc.])
+ else
+ AC_LIBOBJ([frexp])
fi
])
-dnl Test whether frexp() can be used without linking with libm.
-dnl Set gl_cv_func_frexp_no_libm to 'yes' or 'no' accordingly.
-AC_DEFUN([gl_CHECK_FREXP_NO_LIBM],
-[
- AC_CACHE_CHECK([whether frexp() can be used without linking with libm],
- [gl_cv_func_frexp_no_libm],
- [
- AC_LINK_IFELSE(
- [AC_LANG_PROGRAM(
- [[#include <math.h>
- double x;]],
- [[int e; return frexp (x, &e) > 0;]])],
- [gl_cv_func_frexp_no_libm=yes],
- [gl_cv_func_frexp_no_libm=no])
- ])
-])
-
dnl Test whether frexp() works also on denormalized numbers (this fails e.g. on
dnl NetBSD 3.0), on infinite numbers (this fails e.g. on IRIX 6.5 and mingw),
-dnl and on negative zero (this fails e.g. on NetBSD 4.99 and mingw).
+dnl and on negative zero (this fails e.g. on NetBSD 4.99).
AC_DEFUN([gl_FUNC_FREXP_WORKS],
[
AC_REQUIRE([AC_PROG_CC])
AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
- AC_CHECK_DECLS_ONCE([alarm])
AC_CACHE_CHECK([whether frexp works], [gl_cv_func_frexp_works],
[
- AC_RUN_IFELSE(
- [AC_LANG_SOURCE([[
+ AC_TRY_RUN([
#include <float.h>
#include <math.h>
#include <string.h>
-#if HAVE_DECL_ALARM
-# include <signal.h>
-# include <unistd.h>
-#endif
-/* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0.
- ICC 10.0 has a bug when optimizing the expression -zero.
- The expression -DBL_MIN * DBL_MIN does not work when cross-compiling
- to PowerPC on Mac OS X 10.5. */
-#if defined __hpux || defined __sgi || defined __ICC
-static double
-compute_minus_zero (void)
-{
- return -DBL_MIN * DBL_MIN;
-}
-# define minus_zero compute_minus_zero ()
-#else
-double minus_zero = -0.0;
-#endif
int main()
{
- int result = 0;
int i;
volatile double x;
+/* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0.
+ So we use -zero instead. */
double zero = 0.0;
-#if HAVE_DECL_ALARM
- /* NeXTstep 3.3 frexp() runs into an endless loop when called on an infinite
- number. Let the test fail in this case. */
- signal (SIGALRM, SIG_DFL);
- alarm (5);
-#endif
/* Test on denormalized numbers. */
for (i = 1, x = 1.0; i >= DBL_MIN_EXP; i--, x *= 0.5)
;
@@ -141,32 +117,30 @@ int main()
/* On machines with IEEE754 arithmetic: x = 1.11254e-308, exp = -1022.
On NetBSD: y = 0.75. Correct: y = 0.5. */
if (y != 0.5)
- result |= 1;
+ return 1;
}
/* Test on infinite numbers. */
- x = 1.0 / zero;
+ x = 1.0 / 0.0;
{
int exp;
double y = frexp (x, &exp);
if (y != x)
- result |= 2;
+ return 1;
}
/* Test on negative zero. */
- x = minus_zero;
+ x = -zero;
{
int exp;
double y = frexp (x, &exp);
if (memcmp (&y, &x, sizeof x))
- result |= 4;
+ return 1;
}
- return result;
-}]])],
- [gl_cv_func_frexp_works=yes],
- [gl_cv_func_frexp_works=no],
- [case "$host_os" in
- netbsd* | irix* | mingw*) gl_cv_func_frexp_works="guessing no";;
- *) gl_cv_func_frexp_works="guessing yes";;
- esac
- ])
+ return 0;
+}], [gl_cv_func_frexp_works=yes], [gl_cv_func_frexp_works=no],
+ [case "$host_os" in
+ netbsd* | irix* | mingw*) gl_cv_func_frexp_works="guessing no";;
+ *) gl_cv_func_frexp_works="guessing yes";;
+ esac
+ ])
])
])