diff --git a/sys/dev/aac/aac_debug.c b/sys/dev/aac/aac_debug.c
index 3f29a836210b..285b893ef45f 100644
--- a/sys/dev/aac/aac_debug.c
+++ b/sys/dev/aac/aac_debug.c
@@ -182,7 +182,7 @@ aac_panic(struct aac_softc *sc, char *reason)
  * Print a FIB
  */
 void
-aac_print_fib(struct aac_softc *sc, struct aac_fib *fib, char *caller)
+aac_print_fib(struct aac_softc *sc, struct aac_fib *fib, const char *caller)
 {
 	device_printf(sc->aac_dev, "%s: FIB @ %p\n", caller, fib);
 	device_printf(sc->aac_dev, "  XferState %b\n", fib->Header.XferState,
diff --git a/sys/dev/aac/aacvar.h b/sys/dev/aac/aacvar.h
index 30d5535b3dc5..d82f29edda64 100644
--- a/sys/dev/aac/aacvar.h
+++ b/sys/dev/aac/aacvar.h
@@ -412,7 +412,7 @@ extern int		aac_sync_fib(struct aac_softc *sc, u_int32_t command,
 extern void	aac_print_queues(struct aac_softc *sc);
 extern void	aac_panic(struct aac_softc *sc, char *reason);
 extern void	aac_print_fib(struct aac_softc *sc, struct aac_fib *fib,
-			      char *caller);
+			      const char *caller);
 extern void	aac_print_aif(struct aac_softc *sc,
 			      struct aac_aif_command *aif);