diff --git a/rtengine/FTblockDN.cc b/rtengine/FTblockDN.cc
index 8ff22864c..6c608cfc9 100644
--- a/rtengine/FTblockDN.cc
+++ b/rtengine/FTblockDN.cc
@@ -2106,7 +2106,7 @@ float ImProcFunctions::MadMax(float * DataList, int & max, int datalen)
 
 float ImProcFunctions::Mad(float * DataList, const int datalen)
 {
-    if(datalen <= 0) { // Avoid possible buffer underrun
+    if(datalen <= 1) { // Avoid possible buffer underrun
         return 0;
     }
 
@@ -2135,7 +2135,7 @@ float ImProcFunctions::Mad(float * DataList, const int datalen)
 
 float ImProcFunctions::MadRgb(float * DataList, const int datalen)
 {
-    if(datalen <= 0) { // Avoid possible buffer underrun
+    if(datalen <= 1) { // Avoid possible buffer underrun
         return 0;
     }
 
diff --git a/rtengine/improccoordinator.h b/rtengine/improccoordinator.h
index 776484791..0fb0041f3 100644
--- a/rtengine/improccoordinator.h
+++ b/rtengine/improccoordinator.h
@@ -326,12 +326,13 @@ public:
         return imgsrc;
     }
 
-    struct {
+    struct DenoiseInfoStore {
+        DenoiseInfoStore () : valid(false) {}
         float chM;
         float max_r[9];
         float max_b[9];
         float ch_M[9];
-        bool valid = false;
+        bool valid;
 
     } denoiseInfoStore;