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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 17:39:29 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 17:39:29 +0000
commit8ffec2a3aba6f114784e11f89ef1d57a096ae540 (patch)
treeccebcbad06203e8241a8e7249f8e6c478a3682ea /m4/frexp.m4
parentInitial commit. (diff)
downloadcoreutils-8ffec2a3aba6f114784e11f89ef1d57a096ae540.tar.xz
coreutils-8ffec2a3aba6f114784e11f89ef1d57a096ae540.zip
Adding upstream version 8.32.upstream/8.32upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'm4/frexp.m4')
-rw-r--r--m4/frexp.m4181
1 files changed, 181 insertions, 0 deletions
diff --git a/m4/frexp.m4 b/m4/frexp.m4
new file mode 100644
index 0000000..5d977d4
--- /dev/null
+++ b/m4/frexp.m4
@@ -0,0 +1,181 @@
+# frexp.m4 serial 16
+dnl Copyright (C) 2007-2020 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.])
+ 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.])
+ 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).
+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([[
+#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;
+ 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)
+ ;
+ 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 / zero;
+ {
+ 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*) gl_cv_func_frexp_works="guessing no" ;;
+ mingw*) # Guess yes with MSVC, no with mingw.
+ AC_EGREP_CPP([Good], [
+#ifdef _MSC_VER
+ Good
+#endif
+ ],
+ [gl_cv_func_frexp_works="guessing yes"],
+ [gl_cv_func_frexp_works="guessing no"])
+ ;;
+ *) gl_cv_func_frexp_works="guessing yes" ;;
+ esac
+ ])
+ ])
+])