add some signbit() tests

1 files changed, 16 insertions, 0 deletions

diff --git a/math.c b/math.c
index 5120b93..3cf65e6 100644
--- a/math.c
+++ b/math.c
@@ -6,6 +6,13 @@ void test_math_h(void)
 	int iexp = 1;
 	double iptr = 0;
 
+	long double ldm1 = -1.0;
+	double dm1 = -1.0;
+	float fm1 = -1.0;
+	long double ld1 =  1.0;
+	double d1 = 1.0;
+	float f1 = 1.0;
+
 	testing_header("math.h");
 
 	test_defined(HUGE_VAL);
@@ -33,5 +40,14 @@ void test_math_h(void)
 	test_double(floor(0.9), 0);
 	test_double(fmod(1, 1), 0);
 
+	#if defined __STDC_VERSION__ && 19901 <= __STDC_VERSION__
+	test_int_equals(signbit(ldm1), 1);
+	test_int_equals(signbit(dm1), 1);
+	test_int_equals(signbit(fm1), 1);
+	test_int_equals(signbit(ld1), 0);
+	test_int_equals(signbit(d1), 0);
+	test_int_equals(signbit(f1), 0);
+	#endif
+
 	testing_end();
 }