diff --git a/sim/common/ChangeLog b/sim/common/ChangeLog
index 9153cb5fbd2..3edb464b768 100644
--- a/sim/common/ChangeLog
+++ b/sim/common/ChangeLog
@@ -1,3 +1,8 @@
+2010-03-30  Mike Frysinger  <vapier@gentoo.org>
+
+	* sim-utils.c (sim_io_eprintf_cpu): Use %s with printf string.
+	* sim-hw.c (hw_option_handler): Likewise.
+
 2010-03-30  Mike Frysinger  <vapier@gentoo.org>
 
 	* sim-watch.c (watchpoint_type_to_str): Add const to return.
diff --git a/sim/common/sim-hw.c b/sim/common/sim-hw.c
index d9868d3264e..74814920fef 100644
--- a/sim/common/sim-hw.c
+++ b/sim/common/sim-hw.c
@@ -257,7 +257,7 @@ hw_option_handler (struct sim_state *sd, sim_cpu *cpu, int opt,
 
     case OPTION_HW_DEVICE:
       {
-	hw_tree_parse (STATE_HW (sd)->tree, arg);
+	hw_tree_parse (STATE_HW (sd)->tree, "%s", arg);
 	return SIM_RC_OK;
       }
 
diff --git a/sim/common/sim-utils.c b/sim/common/sim-utils.c
index fb84eb3b124..9f9104e1b0e 100644
--- a/sim/common/sim-utils.c
+++ b/sim/common/sim-utils.c
@@ -170,7 +170,7 @@ sim_io_eprintf_cpu (sim_cpu *cpu, const char *fmt, ...)
   va_list ap;
 
   va_start (ap, fmt);
-  sim_io_eprintf (sd, sim_cpu_msg_prefix (cpu));
+  sim_io_eprintf (sd, "%s", sim_cpu_msg_prefix (cpu));
   sim_io_evprintf (sd, fmt, ap);
   va_end (ap);
 }