diff --git a/rtengine/klt/writeFeatures.c b/rtengine/klt/writeFeatures.c
index 78658c121..a97ac8b8f 100644
--- a/rtengine/klt/writeFeatures.c
+++ b/rtengine/klt/writeFeatures.c
@@ -229,7 +229,7 @@ static void _printHeader(
   if (fp != stderr)  {
     fprintf(fp, "Feel free to place comments here.\n\n\n");
     fprintf(fp, "!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!\n");
-    fprintf(fp, warning_line);
+    fprintf(fp, "%s", warning_line);
     fprintf(fp, "\n");
   }
   fprintf(fp, "------------------------------\n");
diff --git a/rtgui/mydiagonalcurve.cc b/rtgui/mydiagonalcurve.cc
index 4c8ec026a..6d21b4436 100644
--- a/rtgui/mydiagonalcurve.cc
+++ b/rtgui/mydiagonalcurve.cc
@@ -726,7 +726,7 @@ int diagonalmchistupdate (void* data) {
 
 void MyDiagonalCurve::updateBackgroundHistogram (LUTu & hist) {
 	
-    if (hist!=NULL) {
+    if (hist) {
         //memcpy (bghist, hist, 256*sizeof(unsigned int));
         for (int i=0; i<256; i++) bghist[i]=hist[i];
         //hist = bghist;