Fix static analysis warnings

With switching to clang-7.0.1 we got new warnings. With this change the
warnings are back to 0 for all configurations (excluding warnings in
third_party)

BUG=webm:1616

Change-Id: I25ceb592c425394e8f14d333fb5680144f892213

6 files changed, 17 insertions, 6 deletions

diff --git a/tools/tiny_ssim.c b/tools/tiny_ssim.c
index f62f7f57e..ff4634ade 100644
--- a/tools/tiny_ssim.c
+++ b/tools/tiny_ssim.c
@@ -326,6 +326,8 @@ int main(int argc, char *argv[]) {
   input_file_t in[2];
   double peak = 255.0;
 
+  memset(in, 0, sizeof(in));
+
   if (argc < 2) {
     fprintf(stderr,
             "Usage: %s file1.{yuv|y4m} file2.{yuv|y4m}"
diff --git a/vp8/encoder/pickinter.c b/vp8/encoder/pickinter.c
index 6bb3cacc5..dc72eed88 100644
--- a/vp8/encoder/pickinter.c
+++ b/vp8/encoder/pickinter.c
@@ -563,7 +563,7 @@ void vp8_pick_inter_mode(VP8_COMP *cpi, MACROBLOCK *x, int recon_yoffset,
   MACROBLOCKD *xd = &x->e_mbd;
   MB_MODE_INFO best_mbmode;
 
-  int_mv best_ref_mv_sb[2];
+  int_mv best_ref_mv_sb[2] = { { 0 }, { 0 } };
   int_mv mode_mv_sb[2][MB_MODE_COUNT];
   int_mv best_ref_mv;
   int_mv *mode_mv;
@@ -601,7 +601,7 @@ void vp8_pick_inter_mode(VP8_COMP *cpi, MACROBLOCK *x, int recon_yoffset,
   /* search range got from mv_pred(). It uses step_param levels. (0-7) */
   int sr = 0;
 
-  unsigned char *plane[4][3];
+  unsigned char *plane[4][3] = { { 0, 0 } };
   int ref_frame_map[4];
   int sign_bias = 0;
   int dot_artifact_candidate = 0;
@@ -630,13 +630,16 @@ void vp8_pick_inter_mode(VP8_COMP *cpi, MACROBLOCK *x, int recon_yoffset,
       }
     }
 #endif
+    assert(plane[LAST_FRAME][0] != NULL);
     dot_artifact_candidate = check_dot_artifact_candidate(
         cpi, x, target_y, stride, plane[LAST_FRAME][0], mb_row, mb_col, 0);
     // If not found in Y channel, check UV channel.
     if (!dot_artifact_candidate) {
+      assert(plane[LAST_FRAME][1] != NULL);
       dot_artifact_candidate = check_dot_artifact_candidate(
           cpi, x, target_u, stride_uv, plane[LAST_FRAME][1], mb_row, mb_col, 1);
       if (!dot_artifact_candidate) {
+        assert(plane[LAST_FRAME][2] != NULL);
         dot_artifact_candidate = check_dot_artifact_candidate(
             cpi, x, target_v, stride_uv, plane[LAST_FRAME][2], mb_row, mb_col,
             2);
diff --git a/vp8/encoder/rdopt.c b/vp8/encoder/rdopt.c
index 5252e9ee4..79a858e43 100644
--- a/vp8/encoder/rdopt.c
+++ b/vp8/encoder/rdopt.c
@@ -989,7 +989,7 @@ static void rd_check_segment(VP8_COMP *cpi, MACROBLOCK *x, BEST_SEG_INFO *bsi,
   br += rate;
 
   for (i = 0; i < label_count; ++i) {
-    int_mv mode_mv[B_MODE_COUNT];
+    int_mv mode_mv[B_MODE_COUNT] = { { 0 }, { 0 } };
     int best_label_rd = INT_MAX;
     B_PREDICTION_MODE mode_selected = ZERO4X4;
     int bestlabelyrate = 0;
@@ -1767,7 +1767,7 @@ void vp8_rd_pick_inter_mode(VP8_COMP *cpi, MACROBLOCK *x, int recon_yoffset,
   /* search range got from mv_pred(). It uses step_param levels. (0-7) */
   int sr = 0;
 
-  unsigned char *plane[4][3];
+  unsigned char *plane[4][3] = { { 0, 0 } };
   int ref_frame_map[4];
   int sign_bias = 0;
 
@@ -1850,6 +1850,9 @@ void vp8_rd_pick_inter_mode(VP8_COMP *cpi, MACROBLOCK *x, int recon_yoffset,
 
     /* everything but intra */
     if (x->e_mbd.mode_info_context->mbmi.ref_frame) {
+      assert(plane[this_ref_frame][0] != NULL &&
+             plane[this_ref_frame][1] != NULL &&
+             plane[this_ref_frame][2] != NULL);
       x->e_mbd.pre.y_buffer = plane[this_ref_frame][0];
       x->e_mbd.pre.u_buffer = plane[this_ref_frame][1];
       x->e_mbd.pre.v_buffer = plane[this_ref_frame][2];
diff --git a/vp9/decoder/vp9_decodemv.c b/vp9/decoder/vp9_decodemv.c
index 0a781413b..943fe478a 100644
--- a/vp9/decoder/vp9_decodemv.c
+++ b/vp9/decoder/vp9_decodemv.c
@@ -696,7 +696,7 @@ static void read_inter_block_mode_info(VP9Decoder *const pbi,
   VP9_COMMON *const cm = &pbi->common;
   const BLOCK_SIZE bsize = mi->sb_type;
   const int allow_hp = cm->allow_high_precision_mv;
-  int_mv best_ref_mvs[2];
+  int_mv best_ref_mvs[2] = { { 0 }, { 0 } };
   int ref, is_compound;
   uint8_t inter_mode_ctx;
   const POSITION *const mv_ref_search = mv_ref_blocks[bsize];
diff --git a/vp9/encoder/vp9_resize.c b/vp9/encoder/vp9_resize.c
index 23a320ae5..7486dee25 100644
--- a/vp9/encoder/vp9_resize.c
+++ b/vp9/encoder/vp9_resize.c
@@ -506,10 +506,12 @@ static void highbd_interpolate(const uint16_t *const input, int inlength,
       sub_pel = (y >> (INTERP_PRECISION_BITS - SUBPEL_BITS)) & SUBPEL_MASK;
       filter = interp_filters[sub_pel];
       sum = 0;
-      for (k = 0; k < INTERP_TAPS; ++k)
+      for (k = 0; k < INTERP_TAPS; ++k) {
+        assert(int_pel - INTERP_TAPS / 2 + 1 + k < inlength);
         sum += filter[k] * input[(int_pel - INTERP_TAPS / 2 + 1 + k < 0
                                       ? 0
                                       : int_pel - INTERP_TAPS / 2 + 1 + k)];
+      }
       *optr++ = clip_pixel_highbd(ROUND_POWER_OF_TWO(sum, FILTER_BITS), bd);
     }
     // Middle part.
diff --git a/vp9/encoder/vp9_subexp.c b/vp9/encoder/vp9_subexp.c
index e8212ce05..19bbd5373 100644
--- a/vp9/encoder/vp9_subexp.c
+++ b/vp9/encoder/vp9_subexp.c
@@ -71,6 +71,7 @@ static int remap_prob(int v, int m) {
   else
     i = recenter_nonneg(MAX_PROB - 1 - v, MAX_PROB - 1 - m) - 1;
 
+  assert(i >= 0 && (size_t)i < sizeof(map_table));
   i = map_table[i];
   return i;
 }