Be extra picky with the casts.

diff --git a/klibc/jrand48.c b/klibc/jrand48.c
index a2ead11..660a6e5 100644
--- a/klibc/jrand48.c
+++ b/klibc/jrand48.c
@@ -10,15 +10,15 @@
   uint64_t x;
 
   /* The xsubi[] array is littleendian by spec */
-  x = (uint64_t)xsubi[0] +
-    ((uint64_t)xsubi[1] << 16) +
-    ((uint64_t)xsubi[2] << 32);
+  x = (uint64_t)(uint16_t)xsubi[0] +
+    ((uint64_t)(uint16_t)xsubi[1] << 16) +
+    ((uint64_t)(uint16_t)xsubi[2] << 32);
 
   x = (0x5deece66dULL * x) + 0xb;
   
-  xsubi[0] = (unsigned short)x;
-  xsubi[1] = (unsigned short)(x >> 16);
-  xsubi[2] = (unsigned short)(x >> 32);
+  xsubi[0] = (unsigned short)(uint16_t)x;
+  xsubi[1] = (unsigned short)(uint16_t)(x >> 16);
+  xsubi[2] = (unsigned short)(uint16_t)(x >> 32);
 
   return (long)(int32_t)(x >> 16);
 }