More issues found by static analysis

modules/imgproc/src/contours.cpp

@@ -855,7 +855,6 @@ icvTraceContour_32s( int *ptr, int step, int *stop_ptr, int is_hole )
         for( ;; )
         {
             CV_Assert(i3 != NULL);
-            s_end = s;
             s = std::min(s, MAX_SIZE - 1);
 
             while( s < MAX_SIZE - 1 )
@@ -1479,7 +1478,7 @@ icvFindContoursInInterval( const CvArr* src,
     cv::Ptr<CvMemStorage> storage01;
     CvSeq* first = 0;
 
-    int i, j, k, n;
+    int j, k, n;
 
     uchar*  src_data = 0;
     int  img_step = 0;
@@ -1547,7 +1546,6 @@ icvFindContoursInInterval( const CvArr* src,
 
     // First line. None of runs is binded
     tmp.pt.y = 0;
-    i = 0;
     CV_WRITE_SEQ_ELEM( tmp, writer );
     upper_line = (CvLinkedRunPoint*)CV_GET_WRITTEN_ELEM( writer );
 
@@ -1580,7 +1578,7 @@ icvFindContoursInInterval( const CvArr* src,
     last_elem = tmp_prev;
     tmp_prev->next = 0;
 
-    for( i = 1; i < img_size.height; i++ )
+    for( int i = 1; i < img_size.height; i++ )
     {
 //------// Find runs in next line
         src_data += img_step;

modules/imgproc/src/drawing.cpp

@@ -338,7 +338,6 @@ LineAA( Mat& img, Point2l pt1, Point2l pt2, const void* color )
 
     if( ax > ay )
     {
-        dx = ax;
         dy = (dy ^ j) - j;
         pt1.x ^= pt2.x & j;
         pt2.x ^= pt1.x & j;
@@ -362,7 +361,6 @@ LineAA( Mat& img, Point2l pt1, Point2l pt2, const void* color )
     }
     else
     {
-        dy = ay;
         dx = (dx ^ i) - i;
         pt1.x ^= pt2.x & i;
         pt2.x ^= pt1.x & i;
@@ -677,7 +675,6 @@ Line2( Mat& img, Point2l pt1, Point2l pt2, const void* color)
 
     if( ax > ay )
     {
-        dx = ax;
         dy = (dy ^ j) - j;
         pt1.x ^= pt2.x & j;
         pt2.x ^= pt1.x & j;
@@ -692,7 +689,6 @@ Line2( Mat& img, Point2l pt1, Point2l pt2, const void* color)
     }
     else
     {
-        dy = ay;
         dx = (dx ^ i) - i;
         pt1.x ^= pt2.x & i;
         pt2.x ^= pt1.x & i;

modules/imgproc/src/filter.avx2.cpp

@@ -128,8 +128,6 @@ int SymmColumnVec_32f_Symm_AVX(const float** src, const float* ky, float* dst, f
         for( k = 1; k <= ksize2; k++ )
         {
             f = _mm_set1_ps(ky[k]);
-            S = src[k] + i;
-            S2 = src[-k] + i;
             x0 = _mm_add_ps(_mm_load_ps(src[k]+i), _mm_load_ps(src[-k] + i));
             s0 = _mm_add_ps(s0, _mm_mul_ps(x0, f));
         }
@@ -144,7 +142,7 @@ int SymmColumnVec_32f_Symm_AVX(const float** src, const float* ky, float* dst, f
 int SymmColumnVec_32f_Unsymm_AVX(const float** src, const float* ky, float* dst, float delta, int width, int ksize2)
 {
     int i = 0, k;
-    const float *S, *S2;
+    const float *S2;
     const __m128 d4 = _mm_set1_ps(delta);
     const __m256 d8 = _mm256_set1_ps(delta);
 
@@ -152,11 +150,10 @@ int SymmColumnVec_32f_Unsymm_AVX(const float** src, const float* ky, float* dst,
     {
         __m256 f, s0 = d8, s1 = d8;
         __m256 x0;
-        S = src[0] + i;
 
         for (k = 1; k <= ksize2; k++)
         {
-            S = src[k] + i;
+            const float *S = src[k] + i;
             S2 = src[-k] + i;
             f = _mm256_set1_ps(ky[k]);
             x0 = _mm256_sub_ps(_mm256_loadu_ps(S), _mm256_loadu_ps(S2));

modules/imgproc/src/floodfill.cpp

@@ -467,7 +467,7 @@ int cv::floodFill( InputOutputArray _image, InputOutputArray _mask,
     if( rect )
         *rect = Rect();
 
-    int i, connectivity = flags & 255;
+    int i;
     union {
         uchar b[4];
         int i[4];
@@ -491,9 +491,8 @@ int cv::floodFill( InputOutputArray _image, InputOutputArray _mask,
         CV_Error( CV_StsBadArg, "Number of channels in input image must be 1 or 3" );
     }
 
-    if( connectivity == 0 )
-        connectivity = 4;
-    else if( connectivity != 4 && connectivity != 8 )
+    const int connectivity = flags & 255;
+    if( connectivity != 0 && connectivity != 4 && connectivity != 8 )
         CV_Error( CV_StsBadFlag, "Connectivity must be 4, 0(=4) or 8" );
 
     bool is_simple = mask.empty() && (flags & FLOODFILL_MASK_ONLY) == 0;

modules/imgproc/src/histogram.cpp

@@ -1930,7 +1930,7 @@ double cv::compareHist( InputArray _H1, InputArray _H2, int method )
     Mat planes[2];
     NAryMatIterator it(arrays, planes);
     double result = 0;
-    int j, len = (int)it.size;
+    int j;
 
     CV_Assert( H1.type() == H2.type() && H1.depth() == CV_32F );
 
@@ -1946,7 +1946,7 @@ double cv::compareHist( InputArray _H1, InputArray _H2, int method )
     {
         const float* h1 = it.planes[0].ptr<float>();
         const float* h2 = it.planes[1].ptr<float>();
-        len = it.planes[0].rows*it.planes[0].cols*H1.channels();
+        const int len = it.planes[0].rows*it.planes[0].cols*H1.channels();
         j = 0;
 
         if( (method == CV_COMP_CHISQR) || (method == CV_COMP_CHISQR_ALT))

modules/imgproc/src/hough.cpp

@@ -413,7 +413,6 @@ HoughLinesSDiv( InputArray image, OutputArray lines, int type,
                 // Find peaks in maccum...
                 for( index = 0; index < sfn; index++ )
                 {
-                    i = 0;
                     int pos = (int)(lst.size() - 1);
                     if( pos < 0 || lst[pos].value < mcaccum[index] )
                     {

modules/imgproc/src/min_enclosing_triangle.cpp

@@ -401,7 +401,6 @@ static void findMinimumAreaEnclosingTriangle(const std::vector<cv::Point2f> &pol
 
     a = 1;
     b = 2;
-    c = 0;
 
     // Main algorithm steps