1 files changed, 248 insertions, 0 deletions
diff --git a/gnulib_m4/isnanl.m4 b/gnulib_m4/isnanl.m4
new file mode 100644
index 0000000..bb39d02
--- /dev/null
+++ b/gnulib_m4/isnanl.m4
@@ -0,0 +1,248 @@
+# isnanl.m4 serial 22
+dnl Copyright (C) 2007-2023 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],
+[
+  AC_REQUIRE([gl_MATH_H_DEFAULTS])
+  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
+  dnl The variable gl_func_isnanl set here is used by isnan.m4.
+  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 $gl_func_isnanl != yes; then
+    HAVE_ISNANL=0
+  fi
+  AC_SUBST([ISNANL_LIBM])
+])
+
+AC_DEFUN([gl_FUNC_ISNANL_NO_LIBM],
+[
+  gl_HAVE_ISNANL_NO_LIBM
+  gl_func_isnanl_no_libm=$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 $gl_func_isnanl_no_libm = yes; then
+    AC_DEFINE([HAVE_ISNANL_IN_LIBC], [1],
+      [Define if the isnan(long double) function is available in libc.])
+  fi
+])
+
+dnl Prerequisites of replacement isnanl definition. It does not need -lm.
+AC_DEFUN([gl_PREREQ_ISNANL],
+[
+  gl_LONG_DOUBLE_EXPONENT_LOCATION
+  AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
+])
+
+dnl Test whether isnanl() can be used without libm.
+AC_DEFUN([gl_HAVE_ISNANL_NO_LIBM],
+[
+  AC_CACHE_CHECK([whether isnan(long double) can be used without linking with libm],
+    [gl_cv_func_isnanl_no_libm],
+    [
+      AC_LINK_IFELSE(
+        [AC_LANG_PROGRAM(
+           [[#include <math.h>
+             #if (__GNUC__ >= 4) || (__clang_major__ >= 4)
+             # undef isnanl
+             # define isnanl(x) __builtin_isnan ((long double)(x))
+             #elif defined isnan
+             # undef isnanl
+             # define isnanl(x) isnan ((long double)(x))
+             #endif
+             long double x;]],
+           [[return isnanl (x);]])],
+        [gl_cv_func_isnanl_no_libm=yes],
+        [gl_cv_func_isnanl_no_libm=no])
+    ])
+])
+
+dnl Test whether isnanl() can be used with libm.
+AC_DEFUN([gl_HAVE_ISNANL_IN_LIBM],
+[
+  AC_CACHE_CHECK([whether isnan(long double) can be used with libm],
+    [gl_cv_func_isnanl_in_libm],
+    [
+      save_LIBS="$LIBS"
+      LIBS="$LIBS -lm"
+      AC_LINK_IFELSE(
+        [AC_LANG_PROGRAM(
+           [[#include <math.h>
+             #if (__GNUC__ >= 4) || (__clang_major__ >= 4)
+             # undef isnanl
+             # define isnanl(x) __builtin_isnan ((long double)(x))
+             #elif defined isnan
+             # undef isnanl
+             # define isnanl(x) isnan ((long double)(x))
+             #endif
+             long double x;]],
+           [[return isnanl (x);]])],
+        [gl_cv_func_isnanl_in_libm=yes],
+        [gl_cv_func_isnanl_in_libm=no])
+      LIBS="$save_LIBS"
+    ])
+])
+
+dnl Test whether isnanl() recognizes all canonical numbers which are neither
+dnl finite nor infinite.
+AC_DEFUN([gl_FUNC_ISNANL_WORKS],
+[
+  AC_REQUIRE([AC_PROG_CC])
+  AC_REQUIRE([gl_BIGENDIAN])
+  AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+  AC_CACHE_CHECK([whether isnanl works], [gl_cv_func_isnanl_works],
+    [
+      AC_RUN_IFELSE(
+        [AC_LANG_SOURCE([[
+#include <float.h>
+#include <limits.h>
+#include <math.h>
+#if (__GNUC__ >= 4) || (__clang_major__ >= 4)
+# undef isnanl
+# define isnanl(x) __builtin_isnan ((long double)(x))
+#elif defined 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 { unsigned int word[NWORDS]; long double value; }
+        memory_long_double;
+/* On Irix 6.5, gcc 3.4.3 can't compute compile-time NaN, and needs the
+   runtime type conversion.  */
+#ifdef __sgi
+static long double NaNl ()
+{
+  double zero = 0.0;
+  return zero / zero;
+}
+#else
+# define NaNl() (0.0L / 0.0L)
+#endif
+int main ()
+{
+  int result = 0;
+
+  if (!isnanl (NaNl ()))
+    result |= 1;
+
+  {
+    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 = NaNl ();
+    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))
+      result |= 1;
+  }
+
+#if ((defined __ia64 && LDBL_MANT_DIG == 64) || (defined __x86_64__ || defined __amd64__) || (defined __i386 || defined __i386__ || defined _I386 || defined _M_IX86 || defined _X86_)) && !HAVE_SAME_LONG_DOUBLE_AS_DOUBLE
+/* Representation of an 80-bit 'long double' as an initializer for a sequence
+   of 'unsigned int' words.  */
+# ifdef WORDS_BIGENDIAN
+#  define LDBL80_WORDS(exponent,manthi,mantlo) \
+     { ((unsigned int) (exponent) << 16) | ((unsigned int) (manthi) >> 16), \
+       ((unsigned int) (manthi) << 16) | ((unsigned int) (mantlo) >> 16),   \
+       (unsigned int) (mantlo) << 16                                        \
+     }
+# else
+#  define LDBL80_WORDS(exponent,manthi,mantlo) \
+     { mantlo, manthi, exponent }
+# endif
+  { /* Quiet NaN.  */
+    static memory_long_double x =
+      { LDBL80_WORDS (0xFFFF, 0xC3333333, 0x00000000) };
+    if (!isnanl (x.value))
+      result |= 2;
+  }
+  {
+    /* Signalling NaN.  */
+    static memory_long_double x =
+      { LDBL80_WORDS (0xFFFF, 0x83333333, 0x00000000) };
+    if (!isnanl (x.value))
+      result |= 2;
+  }
+  /* isnanl should return something even for noncanonical values.  */
+  { /* Pseudo-NaN.  */
+    static memory_long_double x =
+      { LDBL80_WORDS (0xFFFF, 0x40000001, 0x00000000) };
+    if (isnanl (x.value) && !isnanl (x.value))
+      result |= 4;
+  }
+  { /* Pseudo-Infinity.  */
+    static memory_long_double x =
+      { LDBL80_WORDS (0xFFFF, 0x00000000, 0x00000000) };
+    if (isnanl (x.value) && !isnanl (x.value))
+      result |= 8;
+  }
+  { /* Pseudo-Zero.  */
+    static memory_long_double x =
+      { LDBL80_WORDS (0x4004, 0x00000000, 0x00000000) };
+    if (isnanl (x.value) && !isnanl (x.value))
+      result |= 16;
+  }
+  { /* Unnormalized number.  */
+    static memory_long_double x =
+      { LDBL80_WORDS (0x4000, 0x63333333, 0x00000000) };
+    if (isnanl (x.value) && !isnanl (x.value))
+      result |= 32;
+  }
+  { /* Pseudo-Denormal.  */
+    static memory_long_double x =
+      { LDBL80_WORDS (0x0000, 0x83333333, 0x00000000) };
+    if (isnanl (x.value) && !isnanl (x.value))
+      result |= 64;
+  }
+#endif
+
+  return result;
+}]])],
+        [gl_cv_func_isnanl_works=yes],
+        [gl_cv_func_isnanl_works=no],
+        [case "$host_os" in
+           mingw*) # Guess yes on mingw, no on MSVC.
+             AC_EGREP_CPP([Known], [
+#ifdef __MINGW32__
+ Known
+#endif
+               ],
+               [gl_cv_func_isnanl_works="guessing yes"],
+               [gl_cv_func_isnanl_works="guessing no"])
+             ;;
+           *) gl_cv_func_isnanl_works="guessing yes" ;;
+         esac
+        ])
+    ])
+])