libm: fix rint/scalb testcase failures

These failures no longer happen:

Failure: Test: scalb (2.0, 0.5) == NaN plus invalid exception
Failure: Test: scalb (3.0, -2.5) == NaN plus invalid exception
Failure: Test: rint (0.5) == 0.0
Failure: Test: rint (1.5) == 2.0
Failure: Test: rint (2.5) == 2.0
Failure: Test: rint (3.5) == 4.0
Failure: Test: rint (4.5) == 4.0
Failure: Test: rint (-0.5) == -0.0
Failure: Test: rint (-1.5) == -2.0
Failure: Test: rint (-2.5) == -2.0
Failure: Test: rint (-3.5) == -4.0
Failure: Test: rint (-4.5) == -4.0

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 18 insertions, 9 deletions

diff --git a/test/math/signgam.c b/test/math/signgam.c
index c60375aec..d79d6afb2 100644
--- a/test/math/signgam.c
+++ b/test/math/signgam.c
@@ -5,14 +5,23 @@
 double zero = 0.0;
 double mzero;
 
-int
-main (void)
+int main(void)
 {
-  double d;
-  mzero = copysign (zero, -1.0);
-  d = lgamma (zero);
-  printf ("%g %d\n", d, signgam);
-  d = lgamma (mzero);
-  printf ("%g %d\n", d, signgam);
-  return 0;
+	double d;
+	int errors = 0;
+
+	mzero = copysign(zero, -1.0);
+
+	d = lgamma(zero);
+	printf("%g %d\n", d, signgam);
+	errors += !(d == HUGE_VAL);
+	errors += !(signgam == 1);
+
+	d = lgamma(mzero);
+	printf("%g %d\n", d, signgam);
+	errors += !(d == HUGE_VAL);
+	errors += !(signgam == -1);
+
+	printf("Errors: %d\n", errors);
+	return errors;
 }