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authorMark H Weaver <mhw@netris.org>2011-03-07 06:27:42 -0500
committerMark H Weaver <mhw@netris.org>2011-03-09 17:06:05 -0500
commitdd36ce77cd899c7b179026603e751e3bb47b2943 (patch)
treed2f26243f1b6bbb025dea3919ce47f7bc29993cc /m4/frexp.m4
parentdf1297956211b7353155c9b54d7e9c22d05ce493 (diff)
downloadguile-dd36ce77cd899c7b179026603e751e3bb47b2943.tar.gz
Update Gnulib; add new modules; remove `round' module.
This updates Gnulib to v0.0-4951-g6ff7b70. * m4/gnulib-cache.m4: Add floor, ceil, frexp, and ldexp. Add wchar as an explicit dependency; it had been present as an indirect dependency before, but no longer. Remove round, which I had requested earlier, but turned out to be unnecessary.
Diffstat (limited to 'm4/frexp.m4')
-rw-r--r--m4/frexp.m4165
1 files changed, 165 insertions, 0 deletions
diff --git a/m4/frexp.m4 b/m4/frexp.m4
new file mode 100644
index 000000000..2e0fb3b47
--- /dev/null
+++ b/m4/frexp.m4
@@ -0,0 +1,165 @@
+# frexp.m4 serial 10
+dnl Copyright (C) 2007-2011 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_FREXP],
+[
+ AC_REQUIRE([gl_MATH_H_DEFAULTS])
+ AC_REQUIRE([gl_CHECK_FREXP_NO_LIBM])
+ FREXP_LIBM=
+ 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="$LIBS -lm"
+ AC_LINK_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <math.h>
+ double x;]],
+ [[int e; return frexp (x, &e) > 0;]])],
+ [gl_cv_func_frexp_in_libm=yes],
+ [gl_cv_func_frexp_in_libm=no])
+ LIBS="$save_LIBS"
+ ])
+ if test $gl_cv_func_frexp_in_libm = yes; then
+ FREXP_LIBM=-lm
+ fi
+ fi
+ if test $gl_cv_func_frexp_no_libm = yes \
+ || test $gl_cv_func_frexp_in_libm = yes; then
+ save_LIBS="$LIBS"
+ LIBS="$LIBS $FREXP_LIBM"
+ gl_FUNC_FREXP_WORKS
+ LIBS="$save_LIBS"
+ case "$gl_cv_func_frexp_works" in
+ *yes) gl_func_frexp=yes ;;
+ *) gl_func_frexp=no; REPLACE_FREXP=1; FREXP_LIBM= ;;
+ esac
+ else
+ gl_func_frexp=no
+ fi
+ 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])
+])
+
+AC_DEFUN([gl_FUNC_FREXP_NO_LIBM],
+[
+ AC_REQUIRE([gl_MATH_H_DEFAULTS])
+ AC_REQUIRE([gl_CHECK_FREXP_NO_LIBM])
+ if test $gl_cv_func_frexp_no_libm = yes; then
+ gl_FUNC_FREXP_WORKS
+ case "$gl_cv_func_frexp_works" in
+ *yes) gl_func_frexp_no_libm=yes ;;
+ *) gl_func_frexp_no_libm=no; REPLACE_FREXP=1 ;;
+ esac
+ else
+ gl_func_frexp_no_libm=no
+ dnl Set REPLACE_FREXP here because the system may have frexp in libm.
+ REPLACE_FREXP=1
+ fi
+ 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).
+AC_DEFUN([gl_FUNC_FREXP_WORKS],
+[
+ AC_REQUIRE([AC_PROG_CC])
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+ AC_CACHE_CHECK([whether frexp works], [gl_cv_func_frexp_works],
+ [
+ AC_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+#include <float.h>
+#include <math.h>
+#include <string.h>
+/* 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 MacOS 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;
+ double zero = 0.0;
+ /* Test on denormalized numbers. */
+ for (i = 1, x = 1.0; i >= DBL_MIN_EXP; i--, x *= 0.5)
+ ;
+ if (x > 0.0)
+ {
+ int exp;
+ double y = frexp (x, &exp);
+ /* 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;
+ }
+ /* Test on infinite numbers. */
+ x = 1.0 / 0.0;
+ {
+ int exp;
+ double y = frexp (x, &exp);
+ if (y != x)
+ result |= 2;
+ }
+ /* Test on negative zero. */
+ x = minus_zero;
+ {
+ int exp;
+ double y = frexp (x, &exp);
+ if (memcmp (&y, &x, sizeof x))
+ result |= 4;
+ }
+ 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
+ ])
+ ])
+])