Index: uspace/lib/math/generic/trunc.c
===================================================================
--- uspace/lib/math/generic/trunc.c	(revision 3385dd3b26afd849db4e380a2afc06d472d89881)
+++ uspace/lib/math/generic/trunc.c	(revision b336613f992c18f8b2ee48fde947974ba750988e)
@@ -68,5 +68,5 @@
 	} else {
 		/* Truncate irrelevant fraction bits */
-		val.parts.fraction &= UINT64_C(0x000fffffffffffff) >> exp;
+		val.parts.fraction &= ~(UINT64_C(0x000fffffffffffff) >> exp);
 	}