initialize firstDir

src/pathops/SkOpBuilder.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkMatrix.h"
 #include "SkOpEdgeBuilder.h"
 #include "SkPathPriv.h"
@@ skipping 88 matching lines @@
     fOps.reset();
 }
 
 /* OPTIMIZATION: Union doesn't need to be all-or-nothing. A run of three or more convex
    paths with union ops could be locally resolved and still improve over doing the
    ops one at a time. */
 bool SkOpBuilder::resolve(SkPath* result) {
     SkPath original = *result;
     int count = fOps.count();
     bool allUnion = true;
-    SkPathPriv::FirstDirection firstDir;
+    SkPathPriv::FirstDirection firstDir = SkPathPriv::kUnknown_FirstDirection;
     for (int index = 0; index < count; ++index) {
         SkPath* test = &fPathRefs[index];
         if (kUnion_SkPathOp != fOps[index] || test->isInverseFillType()) {
             allUnion = false;
             break;
         }
         // If all paths are convex, track direction, reversing as needed.
         if (test->isConvex()) {
             SkPathPriv::FirstDirection dir;
             if (!SkPathPriv::CheapComputeFirstDirection(*test, &dir)) {
                 allUnion = false;
                 break;
             }
-            if (index == 0) {
+            if (firstDir == SkPathPriv::kUnknown_FirstDirection) {
                 firstDir = dir;
             } else if (firstDir != dir) {
                 SkPath temp;
                 temp.reverseAddPath(*test);
                 *test = temp;
             }
             continue;
         }
         // If the path is not convex but its bounds do not intersect the others, simplify is enough.
         const SkRect& testBounds = test->getBounds();
@@ skipping 28 matching lines @@
         FixWinding(&fPathRefs[index]);
         sum.addPath(fPathRefs[index]);
     }
     reset();
     bool success = Simplify(sum, result);
     if (!success) {
         *result = original;
     }
     return success;
 }