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-rw-r--r--gnulib_m4/isnanf.m4197
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diff --git a/gnulib_m4/isnanf.m4 b/gnulib_m4/isnanf.m4
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+# isnanf.m4 serial 18
+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.
+
+dnl Check how to get or define isnanf().
+
+AC_DEFUN([gl_FUNC_ISNANF],
+[
+ AC_REQUIRE([gl_MATH_H_DEFAULTS])
+ ISNANF_LIBM=
+ gl_HAVE_ISNANF_NO_LIBM
+ if test $gl_cv_func_isnanf_no_libm = no; then
+ gl_HAVE_ISNANF_IN_LIBM
+ if test $gl_cv_func_isnanf_in_libm = yes; then
+ ISNANF_LIBM=-lm
+ fi
+ fi
+ dnl The variable gl_func_isnanf set here is used by isnan.m4.
+ if test $gl_cv_func_isnanf_no_libm = yes \
+ || test $gl_cv_func_isnanf_in_libm = yes; then
+ save_LIBS="$LIBS"
+ LIBS="$LIBS $ISNANF_LIBM"
+ gl_ISNANF_WORKS
+ LIBS="$save_LIBS"
+ case "$gl_cv_func_isnanf_works" in
+ *yes) gl_func_isnanf=yes ;;
+ *) gl_func_isnanf=no; ISNANF_LIBM= ;;
+ esac
+ else
+ gl_func_isnanf=no
+ fi
+ if test $gl_func_isnanf != yes; then
+ HAVE_ISNANF=0
+ fi
+ AC_SUBST([ISNANF_LIBM])
+])
+
+dnl Check how to get or define isnanf() without linking with libm.
+
+AC_DEFUN([gl_FUNC_ISNANF_NO_LIBM],
+[
+ gl_HAVE_ISNANF_NO_LIBM
+ if test $gl_cv_func_isnanf_no_libm = yes; then
+ gl_ISNANF_WORKS
+ fi
+ if test $gl_cv_func_isnanf_no_libm = yes \
+ && { case "$gl_cv_func_isnanf_works" in
+ *yes) true;;
+ *) false;;
+ esac
+ }; then
+ gl_func_isnanf_no_libm=yes
+ AC_DEFINE([HAVE_ISNANF_IN_LIBC], [1],
+ [Define if the isnan(float) function is available in libc.])
+ else
+ gl_func_isnanf_no_libm=no
+ fi
+])
+
+dnl Prerequisites of replacement isnanf definition. It does not need -lm.
+AC_DEFUN([gl_PREREQ_ISNANF],
+[
+ gl_FLOAT_EXPONENT_LOCATION
+])
+
+dnl Test whether isnanf() can be used without libm.
+AC_DEFUN([gl_HAVE_ISNANF_NO_LIBM],
+[
+ AC_CACHE_CHECK([whether isnan(float) can be used without linking with libm],
+ [gl_cv_func_isnanf_no_libm],
+ [
+ AC_LINK_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <math.h>
+ #if (__GNUC__ >= 4) || (__clang_major__ >= 4)
+ # undef isnanf
+ # define isnanf(x) __builtin_isnan ((float)(x))
+ #elif defined isnan
+ # undef isnanf
+ # define isnanf(x) isnan ((float)(x))
+ #endif
+ float x;]],
+ [[return isnanf (x);]])],
+ [gl_cv_func_isnanf_no_libm=yes],
+ [gl_cv_func_isnanf_no_libm=no])
+ ])
+])
+
+dnl Test whether isnanf() can be used with libm.
+AC_DEFUN([gl_HAVE_ISNANF_IN_LIBM],
+[
+ AC_CACHE_CHECK([whether isnan(float) can be used with libm],
+ [gl_cv_func_isnanf_in_libm],
+ [
+ save_LIBS="$LIBS"
+ LIBS="$LIBS -lm"
+ AC_LINK_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <math.h>
+ #if (__GNUC__ >= 4) || (__clang_major__ >= 4)
+ # undef isnanf
+ # define isnanf(x) __builtin_isnan ((float)(x))
+ #elif defined isnan
+ # undef isnanf
+ # define isnanf(x) isnan ((float)(x))
+ #endif
+ float x;]],
+ [[return isnanf (x);]])],
+ [gl_cv_func_isnanf_in_libm=yes],
+ [gl_cv_func_isnanf_in_libm=no])
+ LIBS="$save_LIBS"
+ ])
+])
+
+dnl Test whether isnanf() rejects Infinity (this fails on Solaris 2.5.1),
+dnl recognizes a NaN (this fails on IRIX 6.5 with cc), and recognizes a NaN
+dnl with in-memory representation 0x7fbfffff (this fails on IRIX 6.5).
+AC_DEFUN([gl_ISNANF_WORKS],
+[
+ AC_REQUIRE([AC_PROG_CC])
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+ AC_REQUIRE([gl_FLOAT_EXPONENT_LOCATION])
+ AC_CACHE_CHECK([whether isnan(float) works], [gl_cv_func_isnanf_works],
+ [
+ AC_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+#include <math.h>
+#if (__GNUC__ >= 4) || (__clang_major__ >= 4)
+# undef isnanf
+# define isnanf(x) __builtin_isnan ((float)(x))
+#elif defined isnan
+# undef isnanf
+# define isnanf(x) isnan ((float)(x))
+#endif
+/* The Compaq (ex-DEC) C 6.4 compiler chokes on the expression 0.0 / 0.0. */
+#ifdef __DECC
+static float
+NaN ()
+{
+ static float zero = 0.0f;
+ return zero / zero;
+}
+#else
+# define NaN() (0.0f / 0.0f)
+#endif
+#define NWORDS \
+ ((sizeof (float) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
+typedef union { unsigned int word[NWORDS]; float value; } memory_float;
+int main()
+{
+ int result = 0;
+
+ if (isnanf (1.0f / 0.0f))
+ result |= 1;
+
+ if (!isnanf (NaN ()))
+ result |= 2;
+
+#if defined FLT_EXPBIT0_WORD && defined FLT_EXPBIT0_BIT
+ /* The isnanf function should be immune against changes in the sign bit and
+ in the mantissa bits. The xor operation twiddles a bit that can only be
+ a sign bit or a mantissa bit. */
+ if (FLT_EXPBIT0_WORD == 0 && FLT_EXPBIT0_BIT > 0)
+ {
+ memory_float m;
+
+ m.value = NaN ();
+ /* Set the bits below the exponent to 01111...111. */
+ m.word[0] &= -1U << FLT_EXPBIT0_BIT;
+ m.word[0] |= (1U << (FLT_EXPBIT0_BIT - 1)) - 1;
+ if (!isnanf (m.value))
+ result |= 4;
+ }
+#endif
+
+ return result;
+}]])],
+ [gl_cv_func_isnanf_works=yes],
+ [gl_cv_func_isnanf_works=no],
+ [case "$host_os" in
+ irix* | solaris*) gl_cv_func_isnanf_works="guessing no" ;;
+ mingw*) # Guess yes on mingw, no on MSVC.
+ AC_EGREP_CPP([Known], [
+#ifdef __MINGW32__
+ Known
+#endif
+ ],
+ [gl_cv_func_isnanf_works="guessing yes"],
+ [gl_cv_func_isnanf_works="guessing no"])
+ ;;
+ *) gl_cv_func_isnanf_works="guessing yes" ;;
+ esac
+ ])
+ ])
+])