Description: gcc-6 build fixes, cherry-picked from Fedora
From: https://pkgs.fedoraproject.org/cgit/rpms/opencv.git/commit/?id=ca7da00ea608b62859a640493a1cd6c0f5802550
Author: Sérgio M. Basto <sergio@serjux.com>
Last-Update: 2016-10-04

--- opencv-2.4.9.1+dfsg.orig/modules/contrib/src/chamfermatching.cpp
+++ opencv-2.4.9.1+dfsg/modules/contrib/src/chamfermatching.cpp
@@ -966,10 +966,8 @@ void ChamferMatcher::Matching::computeDi
     for (int y=0;y<h;++y) {
         for (int x=0;x<w;++x) {
             // initialize
-            if (&annotate_img!=NULL) {
-                annotate_img.at<Vec2i>(y,x)[0]=x;
-                annotate_img.at<Vec2i>(y,x)[1]=y;
-            }
+            annotate_img.at<Vec2i>(y,x)[0]=x;
+            annotate_img.at<Vec2i>(y,x)[1]=y;
 
             uchar edge_val = edges_img.at<uchar>(y,x);
             if( (edge_val!=0) ) {
@@ -1013,10 +1011,8 @@ void ChamferMatcher::Matching::computeDi
                 dist_img.at<float>(ny,nx) = dist;
                 q.push(std::make_pair(nx,ny));
 
-                if (&annotate_img!=NULL) {
-                    annotate_img.at<Vec2i>(ny,nx)[0]=annotate_img.at<Vec2i>(y,x)[0];
-                    annotate_img.at<Vec2i>(ny,nx)[1]=annotate_img.at<Vec2i>(y,x)[1];
-                }
+                annotate_img.at<Vec2i>(ny,nx)[0]=annotate_img.at<Vec2i>(y,x)[0];
+                annotate_img.at<Vec2i>(ny,nx)[1]=annotate_img.at<Vec2i>(y,x)[1];
             }
         }
     }
@@ -1107,26 +1103,22 @@ ChamferMatcher::Match* ChamferMatcher::M
 
     float cost = (sum_distance/truncate_)/addr.size();
 
+    float* optr = orientation_img.ptr<float>(y)+x;
+    float sum_orientation = 0;
+    int cnt_orientation = 0;
 
-    if (&orientation_img!=NULL) {
-        float* optr = orientation_img.ptr<float>(y)+x;
-        float sum_orientation = 0;
-        int cnt_orientation = 0;
-
-        for (size_t i=0;i<addr.size();++i) {
+    for (size_t i=0;i<addr.size();++i) {
 
-            if(addr[i] < (orientation_img.cols*orientation_img.rows) - (offset.y*orientation_img.cols + offset.x)){
-                                if (tpl->orientations[i]>=-CV_PI && (*(optr+addr[i]))>=-CV_PI) {
-                    sum_orientation += orientation_diff(tpl->orientations[i], (*(optr+addr[i])));
-                    cnt_orientation++;
-                }
+        if(addr[i] < (orientation_img.cols*orientation_img.rows) - (offset.y*orientation_img.cols + offset.x)){
+                            if (tpl->orientations[i]>=-CV_PI && (*(optr+addr[i]))>=-CV_PI) {
+                sum_orientation += orientation_diff(tpl->orientations[i], (*(optr+addr[i])));
+                cnt_orientation++;
             }
         }
+    }
 
-        if (cnt_orientation>0) {
-                        cost = (float)(beta*cost+alpha*(sum_orientation/(2*CV_PI))/cnt_orientation);
-        }
-
+    if (cnt_orientation>0) {
+                    cost = (float)(beta*cost+alpha*(sum_orientation/(2*CV_PI))/cnt_orientation);
     }
 
     if(cost > 0){