diff --git a/src/Cockpit/hud_labl.cxx b/src/Cockpit/hud_labl.cxx
index 95d69142a..8927b113e 100644
--- a/src/Cockpit/hud_labl.cxx
+++ b/src/Cockpit/hud_labl.cxx
@@ -114,7 +114,7 @@ void instr_label::draw(void)
         }
 
     } else {
-        snprintf(label_buffer, sizeof( label_buffer) -1, format_buffer.c_str());
+        snprintf(label_buffer, sizeof( label_buffer)-1, format_buffer.c_str(), 0);
     }
 
     lenstr = getStringWidth(label_buffer);
diff --git a/src/Instrumentation/HUD/HUD_label.cxx b/src/Instrumentation/HUD/HUD_label.cxx
index 98a6a1df0..5cf2bcb57 100644
--- a/src/Instrumentation/HUD/HUD_label.cxx
+++ b/src/Instrumentation/HUD/HUD_label.cxx
@@ -144,7 +144,7 @@ void HUD::Label::draw(void)
     char buf[BUFSIZE+1];
 	buf[ BUFSIZE] = '\0';  // Be sure to terminate properly
     if (_mode == NONE)
-        snprintf(buf, BUFSIZE, _format.c_str());
+        snprintf(buf, BUFSIZE, _format.c_str(), 0);
     else if (_mode == STRING)
         snprintf(buf, BUFSIZE, _format.c_str(), _input.getStringValue());
     else if (_mode == INT)