Index: uspace/lib/c/test/double_to_str.c
===================================================================
--- uspace/lib/c/test/double_to_str.c	(revision 7268bf1477ab3540e4dcf359102dcb4b92317d13)
+++ uspace/lib/c/test/double_to_str.c	(revision 899bdfda27b53bba2ce96d32870c576201ab6ba8)
@@ -176,4 +176,10 @@
 	PCUT_ASSERT_INT_EQUALS(-3, dec);
 	PCUT_ASSERT_STR_EQUALS("1100", buf);
+
+	d = extract_ieee_double(768.0);
+	ret = double_to_fixed_str(d, -1, 3, buf, size, &dec);
+	PCUT_ASSERT_INT_EQUALS(4, ret);
+	PCUT_ASSERT_INT_EQUALS(-3, dec);
+	PCUT_ASSERT_STR_EQUALS("768", buf);
 }