-# isnanl.m4 serial 1
+# isnanl.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,
dnl with or without modifications, as long as this notice is preserved.
-AC_DEFUN([gl_FUNC_ISNANL_NO_LIBM],
+AC_DEFUN([gl_FUNC_ISNANL],
[
- AC_REQUIRE([gt_TYPE_LONGDOUBLE])
- if test $gt_cv_c_long_double = yes; then
- AC_CACHE_CHECK([whether isnan(long double) can be used without linking with libm],
- [gl_cv_func_isnanl_no_libm],
- [
- AC_TRY_LINK([#include <math.h>
- #ifdef isnan
- # undef isnanl
- # define isnanl(x) isnan ((long double)(x))
- #endif
- long double x;],
- [return isnanl (x);],
- [gl_cv_func_isnanl_no_libm=yes],
- [gl_cv_func_isnanl_no_libm=no])
- ])
- if test $gl_cv_func_isnanl_no_libm = yes; then
- AC_DEFINE([HAVE_ISNANL_IN_LIBC], 1,
- [Define if the isnan(long double) function is available in libc.])
- else
- AC_LIBOBJ([isnanl])
- gl_LONG_DOUBLE_EXPONENT_LOCATION
+ ISNANL_LIBM=
+ gl_HAVE_ISNANL_NO_LIBM
+ if test $gl_cv_func_isnanl_no_libm = no; then
+ gl_HAVE_ISNANL_IN_LIBM
+ if test $gl_cv_func_isnanl_in_libm = yes; then
+ ISNANL_LIBM=-lm
fi
fi
+ if test $gl_cv_func_isnanl_no_libm = yes \
+ || test $gl_cv_func_isnanl_in_libm = yes; then
+ save_LIBS="$LIBS"
+ LIBS="$LIBS $ISNANL_LIBM"
+ gl_FUNC_ISNANL_WORKS
+ LIBS="$save_LIBS"
+ case "$gl_cv_func_isnanl_works" in
+ *yes) gl_func_isnanl=yes ;;
+ *) gl_func_isnanl=no; ISNANL_LIBM= ;;
+ esac
+ else
+ gl_func_isnanl=no
+ fi
+ if test $gl_func_isnanl = yes; then
+ AC_DEFINE([HAVE_ISNANL], 1,
+ [Define if the isnan(long double) function is available.])
+ else
+ AC_LIBOBJ([isnanl])
+ gl_LONG_DOUBLE_EXPONENT_LOCATION
+ fi
+ AC_SUBST([ISNANL_LIBM])
+])
+
+AC_DEFUN([gl_FUNC_ISNANL_NO_LIBM],
+[
+ gl_HAVE_ISNANL_NO_LIBM
+ gl_func_isnanl_no_libm=$gl_cv_func_isnanl_no_libm
+ if test $gl_func_isnanl_no_libm = yes; then
+ gl_FUNC_ISNANL_WORKS
+ case "$gl_cv_func_isnanl_works" in
+ *yes) ;;
+ *) gl_func_isnanl_no_libm=no ;;
+ esac
+ fi
+ if test $gl_func_isnanl_no_libm = yes; then
+ AC_DEFINE([HAVE_ISNANL_IN_LIBC], 1,
+ [Define if the isnan(long double) function is available in libc.])
+ else
+ AC_LIBOBJ([isnanl])
+ gl_LONG_DOUBLE_EXPONENT_LOCATION
+ fi
+])
+
+dnl Test whether isnanl() can be used without libm.
+AC_DEFUN([gl_HAVE_ISNANL_NO_LIBM],
+[
+ AC_CACHE_CHECK([whether isnan(long double) can be used without linking with libm],
+ [gl_cv_func_isnanl_no_libm],
+ [
+ AC_TRY_LINK([#include <math.h>
+ #ifdef isnan
+ # undef isnanl
+ # define isnanl(x) isnan ((long double)(x))
+ #endif
+ long double x;],
+ [return isnanl (x);],
+ [gl_cv_func_isnanl_no_libm=yes],
+ [gl_cv_func_isnanl_no_libm=no])
+ ])
+])
+
+dnl Test whether isnanl() can be used with libm.
+AC_DEFUN([gl_HAVE_ISNANL_IN_LIBM],
+[
+ AC_CACHE_CHECK([whether isnan(long double) can be used with libm],
+ [gl_cv_func_isnanl_in_libm],
+ [
+ save_LIBS="$LIBS"
+ LIBS="$LIBS -lm"
+ AC_TRY_LINK([#include <math.h>
+ #ifdef isnan
+ # undef isnanl
+ # define isnanl(x) isnan ((long double)(x))
+ #endif
+ long double x;],
+ [return isnanl (x);],
+ [gl_cv_func_isnanl_in_libm=yes],
+ [gl_cv_func_isnanl_in_libm=no])
+ LIBS="$save_LIBS"
+ ])
+])
+
+dnl Test whether isnanl() recognizes all numbers which are neither finite nor
+dnl infinite. This test fails e.g. on NetBSD/i386.
+AC_DEFUN([gl_FUNC_ISNANL_WORKS],
+[
+ AC_REQUIRE([AC_PROG_CC])
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+ AC_CACHE_CHECK([whether isnanl works], [gl_cv_func_isnanl_works],
+ [
+ AC_TRY_RUN([
+#include <limits.h>
+#include <math.h>
+#ifdef isnan
+# undef isnanl
+# define isnanl(x) isnan ((long double)(x))
+#endif
+#define NWORDS \
+ ((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
+typedef union { long double value; unsigned int word[NWORDS]; }
+ memory_long_double;
+int main ()
+{
+ memory_long_double m;
+ unsigned int i;
+
+ /* The isnanl function should be immune against changes in the sign bit and
+ in the mantissa bits. The xor operation twiddles a bit that can only be
+ a sign bit or a mantissa bit (since the exponent never extends to
+ bit 31). */
+ m.value = 0.0L / 0.0L;
+ m.word[NWORDS / 2] ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
+ for (i = 0; i < NWORDS; i++)
+ m.word[i] |= 1;
+ if (!isnanl (m.value))
+ return 1;
+
+ return 0;
+}], [gl_cv_func_isnanl_works=yes], [gl_cv_func_isnanl_works=no],
+ [case "$host_os" in
+ netbsd*) gl_cv_func_isnanl_works="guessing no";;
+ *) gl_cv_func_isnanl_works="guessing yes";;
+ esac
+ ])
+ ])
])
AC_DEFUN([gl_LONG_DOUBLE_EXPONENT_LOCATION],
projects / gnulib.git / blobdiff