-# frexp.m4 serial 1
+# frexp.m4 serial 3
dnl Copyright (C) 2007 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
[gl_cv_func_frexp_no_libm],
[
AC_TRY_LINK([#include <math.h>
- long double x;],
+ double x;],
[int e; return frexp (x, &e) > 0;],
[gl_cv_func_frexp_no_libm=yes],
[gl_cv_func_frexp_no_libm=no])
save_LIBS="$LIBS"
LIBS="$LIBS -lm"
AC_TRY_LINK([#include <math.h>
- long double x;],
+ double x;],
[int e; return frexp (x, &e) > 0;],
[gl_cv_func_frexp_in_libm=yes],
[gl_cv_func_frexp_in_libm=no])
else
AC_LIBOBJ([frexp])
fi
+ AC_SUBST([FREXP_LIBM])
])
-dnl Test whether frexp() works also on denormalized numbers.
-dnl This test fails e.g. on NetBSD.
+dnl Test whether frexp() works also on denormalized numbers (this fails e.g. on
+dnl NetBSD 3.0) and on infinite numbers (this fails e.g. on IRIX 6.5).
AC_DEFUN([gl_FUNC_FREXP_WORKS],
[
AC_REQUIRE([AC_PROG_CC])
{
int i;
volatile double x;
+ /* Test on denormalized numbers. */
for (i = 1, x = 1.0; i >= DBL_MIN_EXP; i--, x *= 0.5)
;
if (x > 0.0)
if (y != 0.5)
return 1;
}
+ /* Test on infinite numbers. */
+ x = 1.0 / 0.0;
+ {
+ int exp;
+ double y = frexp (x, &exp);
+ if (y != x)
+ return 1;
+ }
return 0;
}], [gl_cv_func_frexp_works=yes], [gl_cv_func_frexp_works=no],
[case "$host_os" in
- netbsd*) gl_cv_func_frexp_works="guessing no";;
- *) gl_cv_func_frexp_works="guessing yes";;
+ netbsd* | irix*) gl_cv_func_frexp_works="guessing no";;
+ *) gl_cv_func_frexp_works="guessing yes";;
esac
])
])