Index: runtime/parrot/library/Math/Rand.pir
===================================================================
--- runtime/parrot/library/Math/Rand.pir	(revision 37081)
+++ runtime/parrot/library/Math/Rand.pir	(working copy)
@@ -67,6 +67,12 @@
     $I0 = $P0
     $I0 *= 1103515245
     $I0 += 12345
+    ge $I0, 0, noadj
+    $I0 += 0x80000000 # not hit for 64bit int
+    goto done
+noadj:
+    $I0 &= 0xffffffff # noop for 32bit int
+done:
     set $P0, $I0
     $I0 /= 65536
     $I0 %= 32768
Index: t/library/rand.t
===================================================================
--- t/library/rand.t	(revision 37081)
+++ t/library/rand.t	(working copy)
@@ -41,11 +41,11 @@
 .end
 CODE
 16838
-5759
+5758
 10113
-17516
+17515
 16838
-5759
+5758
 OUTPUT
 
 pir_output_is( << 'CODE', << 'OUTPUT', 'RAND_MAX' );