Extent the modf() tests; from Willemijn Coene.

1 files changed, 50 insertions, 18 deletions

diff --git a/src/regress/lib/libc/modf/modf_test.c b/src/regress/lib/libc/modf/modf_test.c
index f732533635..b96618e1f0 100644
--- a/src/regress/lib/libc/modf/modf_test.c
+++ b/src/regress/lib/libc/modf/modf_test.c
@@ -1,35 +1,67 @@
-/* Public domain, 2014, Tobias Ulmer <tobiasu@tmux.org> */
-
-/* Test for bug introduced in 4.4BSD modf() on sparc */
+/*      $OpenBSD: modf_test.c,v 1.2 2023/08/13 06:57:04 miod Exp $      */
 
+#include <assert.h>
 #include <math.h>
 
+/* Test for bug introduced in 4.4BSD modf() on sparc */
+/* Public domain, 2014, Tobias Ulmer <tobiasu@tmux.org> */
+
 #define BIGFLOAT (5e15) /* Number large enough to trigger the "big" case */
 
-int
-main(void)
+void
+modf_sparc(void)
 {
         double f, i;
 
         f = modf(BIGFLOAT, &i);
-        if (i != BIGFLOAT)
-                return 1;
-        if (f != 0.0)
-                return 1;
+        assert(i == BIGFLOAT);
+        assert(f == 0.0);
 
         /* Repeat, maybe we were lucky */
         f = modf(BIGFLOAT, &i);
-        if (i != BIGFLOAT)
-                return 1;
-        if (f != 0.0)
-                return 1;
+        assert(i == BIGFLOAT);
+        assert(f == 0.0);
 
         /* With negative number, for good measure */
         f = modf(-BIGFLOAT, &i);
-        if (i != -BIGFLOAT)
-                return 1;
-        if (f != 0.0)
-                return 1;
+        assert(i == -BIGFLOAT);
+        assert(f == 0.0);
+}
 
-        return 0;
+/* Test for modf() behaviour on Inf and Nan */
+/* Written by Willemijn Coene.  Public domain */
+
+void
+modf_infnan(void)
+{
+        double f, i;
+
+        f = modf(__builtin_inf(), &i);
+        assert(isinf(i));
+        assert(signbit(i) == 0);
+        assert(f == 0.0);
+
+        f = modf(-__builtin_inf(), &i);
+        assert(isinf(i));
+        assert(signbit(i) != 0);
+        assert(f == -0.0);
+
+        f = modf(NAN, &i);
+        assert(isnan(i));
+        assert(signbit(i) == 0);
+        assert(isnan(f));
+        assert(signbit(f) == 0);
+
+        f = modf(-NAN, &i);
+        assert(isnan(i));
+        assert(signbit(i) != 0);
+        assert(isnan(f));
+        assert(signbit(f) != 0);
+}
+
+int
+main(void)
+{
+        modf_sparc();
+        modf_infnan();
 }