+dnl Test whether the *printf family of functions supports infinite and NaN
+dnl 'long double' arguments in the %f, %e, %g directives. (ISO C99, POSIX:2001)
+dnl Result is gl_cv_func_printf_infinite_long_double.
+
+AC_DEFUN([gl_PRINTF_INFINITE_LONG_DOUBLE],
+[
+ AC_REQUIRE([gl_PRINTF_LONG_DOUBLE])
+ AC_REQUIRE([AC_PROG_CC])
+ AC_REQUIRE([gl_BIGENDIAN])
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+ dnl The user can set or unset the variable gl_printf_safe to indicate
+ dnl that he wishes a safe handling of non-IEEE-754 'long double' values.
+ if test -n "$gl_printf_safe"; then
+ AC_DEFINE([CHECK_PRINTF_SAFE], [1],
+ [Define if you wish *printf() functions that have a safe handling of
+ non-IEEE-754 'long double' values.])
+ fi
+ case "$gl_cv_func_printf_long_double" in
+ *yes)
+ AC_CACHE_CHECK([whether printf supports infinite 'long double' arguments],
+ [gl_cv_func_printf_infinite_long_double],
+ [
+ AC_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+]GL_NOCRASH[
+#include <float.h>
+#include <stdio.h>
+#include <string.h>
+static int
+strisnan (const char *string, size_t start_index, size_t end_index)
+{
+ if (start_index < end_index)
+ {
+ if (string[start_index] == '-')
+ start_index++;
+ if (start_index + 3 <= end_index
+ && memcmp (string + start_index, "nan", 3) == 0)
+ {
+ start_index += 3;
+ if (start_index == end_index
+ || (string[start_index] == '(' && string[end_index - 1] == ')'))
+ return 1;
+ }
+ }
+ return 0;
+}
+static char buf[10000];
+static long double zeroL = 0.0L;
+int main ()
+{
+ int result = 0;
+ nocrash_init();
+ if (sprintf (buf, "%Lf", 1.0L / 0.0L) < 0
+ || (strcmp (buf, "inf") != 0 && strcmp (buf, "infinity") != 0))
+ result |= 1;
+ if (sprintf (buf, "%Lf", -1.0L / 0.0L) < 0
+ || (strcmp (buf, "-inf") != 0 && strcmp (buf, "-infinity") != 0))
+ result |= 1;
+ if (sprintf (buf, "%Lf", zeroL / zeroL) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 1;
+ if (sprintf (buf, "%Le", 1.0L / 0.0L) < 0
+ || (strcmp (buf, "inf") != 0 && strcmp (buf, "infinity") != 0))
+ result |= 1;
+ if (sprintf (buf, "%Le", -1.0L / 0.0L) < 0
+ || (strcmp (buf, "-inf") != 0 && strcmp (buf, "-infinity") != 0))
+ result |= 1;
+ if (sprintf (buf, "%Le", zeroL / zeroL) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 1;
+ if (sprintf (buf, "%Lg", 1.0L / 0.0L) < 0
+ || (strcmp (buf, "inf") != 0 && strcmp (buf, "infinity") != 0))
+ result |= 1;
+ if (sprintf (buf, "%Lg", -1.0L / 0.0L) < 0
+ || (strcmp (buf, "-inf") != 0 && strcmp (buf, "-infinity") != 0))
+ result |= 1;
+ if (sprintf (buf, "%Lg", zeroL / zeroL) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 1;
+#if CHECK_PRINTF_SAFE && ((defined __ia64 && LDBL_MANT_DIG == 64) || (defined __x86_64__ || defined __amd64__) || (defined __i386 || defined __i386__ || defined _I386 || defined _M_IX86 || defined _X86_))
+/* 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 union { unsigned int word[4]; long double value; } x =
+ { LDBL80_WORDS (0xFFFF, 0xC3333333, 0x00000000) };
+ if (sprintf (buf, "%Lf", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 2;
+ if (sprintf (buf, "%Le", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 2;
+ if (sprintf (buf, "%Lg", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 2;
+ }
+ {
+ /* Signalling NaN. */
+ static union { unsigned int word[4]; long double value; } x =
+ { LDBL80_WORDS (0xFFFF, 0x83333333, 0x00000000) };
+ if (sprintf (buf, "%Lf", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 2;
+ if (sprintf (buf, "%Le", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 2;
+ if (sprintf (buf, "%Lg", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 2;
+ }
+ { /* Pseudo-NaN. */
+ static union { unsigned int word[4]; long double value; } x =
+ { LDBL80_WORDS (0xFFFF, 0x40000001, 0x00000000) };
+ if (sprintf (buf, "%Lf", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 4;
+ if (sprintf (buf, "%Le", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 4;
+ if (sprintf (buf, "%Lg", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 4;
+ }
+ { /* Pseudo-Infinity. */
+ static union { unsigned int word[4]; long double value; } x =
+ { LDBL80_WORDS (0xFFFF, 0x00000000, 0x00000000) };
+ if (sprintf (buf, "%Lf", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 8;
+ if (sprintf (buf, "%Le", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 8;
+ if (sprintf (buf, "%Lg", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 8;
+ }
+ { /* Pseudo-Zero. */
+ static union { unsigned int word[4]; long double value; } x =
+ { LDBL80_WORDS (0x4004, 0x00000000, 0x00000000) };
+ if (sprintf (buf, "%Lf", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 16;
+ if (sprintf (buf, "%Le", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 16;
+ if (sprintf (buf, "%Lg", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 16;
+ }
+ { /* Unnormalized number. */
+ static union { unsigned int word[4]; long double value; } x =
+ { LDBL80_WORDS (0x4000, 0x63333333, 0x00000000) };
+ if (sprintf (buf, "%Lf", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 32;
+ if (sprintf (buf, "%Le", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 32;
+ if (sprintf (buf, "%Lg", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 32;
+ }
+ { /* Pseudo-Denormal. */
+ static union { unsigned int word[4]; long double value; } x =
+ { LDBL80_WORDS (0x0000, 0x83333333, 0x00000000) };
+ if (sprintf (buf, "%Lf", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 64;
+ if (sprintf (buf, "%Le", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 64;
+ if (sprintf (buf, "%Lg", x.value) < 0
+ || !strisnan (buf, 0, strlen (buf)))
+ result |= 64;
+ }
+#endif
+ return result;
+}]])],
+ [gl_cv_func_printf_infinite_long_double=yes],
+ [gl_cv_func_printf_infinite_long_double=no],
+ [
+changequote(,)dnl
+ case "$host_cpu" in
+ # Guess no on ia64, x86_64, i386.
+ ia64 | x86_64 | i*86) gl_cv_func_printf_infinite_long_double="guessing no";;
+ *)
+ case "$host_os" in
+ # Guess yes on glibc systems.
+ *-gnu*) gl_cv_func_printf_infinite_long_double="guessing yes";;
+ # Guess yes on FreeBSD >= 6.
+ freebsd[1-5]*) gl_cv_func_printf_infinite_long_double="guessing no";;
+ freebsd* | kfreebsd*) gl_cv_func_printf_infinite_long_double="guessing yes";;
+ # Guess yes on HP-UX >= 11.
+ hpux[7-9]* | hpux10*) gl_cv_func_printf_infinite_long_double="guessing no";;
+ hpux*) gl_cv_func_printf_infinite_long_double="guessing yes";;
+ # If we don't know, assume the worst.
+ *) gl_cv_func_printf_infinite_long_double="guessing no";;
+ esac
+ ;;
+ esac
+changequote([,])dnl
+ ])
+ ])
+ ;;
+ *)
+ gl_cv_func_printf_infinite_long_double="irrelevant"
+ ;;
+ esac
+])
+