[make EVALTAG more assertive
John Meacham <john@repetae.net>**20070227071546] hunk ./data/jhc_rts2.c 9
-#define EVALTAG(fn) ((tag_t)((uintptr_t)(fn) | P_LAZY))
+#define EVALTAG(fn) (assert(((uintptr_t)(fn) & 0x3) == 0),(tag_t)((uintptr_t)(fn) | P_LAZY))