--- /dev/null
+#include <string.h>
+#include <stdlib.h>
+
+#define TEST(TYPE, EXT) \
+static TYPE Y##EXT[] = { \
+ 2.0, -2.0, -2.0, -2.0, -2.0, 2.0, -0.0, __builtin_inf##EXT () \
+}; \
+static const TYPE Z##EXT[] = { \
+ 1.0, -1.0, -1.0, -0.0, -0.0, 0.0, -__builtin_inf##EXT (), \
+ __builtin_nan##EXT ("") \
+}; \
+ \
+void test##EXT (void) \
+{ \
+ TYPE r[8]; \
+ /* Make sure to avoid comparing unused bits in the type. */ \
+ memset (r, 0, sizeof r); \
+ r[0] = __builtin_copysign##EXT (1.0, Y##EXT[0]); \
+ r[1] = __builtin_copysign##EXT (1.0, Y##EXT[1]); \
+ r[2] = __builtin_copysign##EXT (-1.0, Y##EXT[2]); \
+ r[3] = __builtin_copysign##EXT (0.0, Y##EXT[3]); \
+ r[4] = __builtin_copysign##EXT (-0.0, Y##EXT[4]); \
+ r[5] = __builtin_copysign##EXT (-0.0, Y##EXT[5]); \
+ r[6] = __builtin_copysign##EXT (__builtin_inf##EXT (), Y##EXT[6]); \
+ r[7] = __builtin_copysign##EXT (-__builtin_nan##EXT (""), Y##EXT[7]); \
+ if (memcmp (r, Z##EXT, sizeof r) != 0) \
+ abort (); \
+}
+
+TEST(float, f)
+TEST(double, )
+TEST(long double, l)
+
+int main()
+{
+ testf();
+ test();
+ testl();
+ return 0;
+}