+
+# Expands to a C program that can be used to test for simultaneous support
+# of 'long long' and 'unsigned long long'. We don't want to say that
+# 'long long' is available if 'unsigned long long' is not, or vice versa,
+# because too many programs rely on the symmetry between signed and unsigned
+# integer types (excluding 'bool').
+AC_DEFUN([_AC_TYPE_LONG_LONG_SNIPPET],
+[
+ AC_LANG_PROGRAM(
+ [[/* For now, do not test the preprocessor; as of 2007 there are too many
+ implementations with broken preprocessors. Perhaps this can
+ be revisited in 2012. In the meantime, code should not expect
+ #if to work with literals wider than 32 bits. */
+ /* Test literals. */
+ long long int ll = 9223372036854775807ll;
+ long long int nll = -9223372036854775807LL;
+ unsigned long long int ull = 18446744073709551615ULL;
+ /* Test constant expressions. */
+ typedef int a[((-9223372036854775807LL < 0 && 0 < 9223372036854775807ll)
+ ? 1 : -1)];
+ typedef int b[(18446744073709551615ULL <= (unsigned long long int) -1
+ ? 1 : -1)];
+ int i = 63;]],
+ [[/* Test availability of runtime routines for shift and division. */
+ long long int llmax = 9223372036854775807ll;
+ unsigned long long int ullmax = 18446744073709551615ull;
+ return ((ll << 63) | (ll >> 63) | (ll < i) | (ll > i)
+ | (llmax / ll) | (llmax % ll)
+ | (ull << 63) | (ull >> 63) | (ull << i) | (ull >> i)
+ | (ullmax / ull) | (ullmax % ull));]])
+])