Bugfix that cause skpdiff to segfault.

tools/skpdiff/SkDiffContext.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkImageDecoder.h"
 #include "SkOSFile.h"
@@ skipping 266 matching lines @@
     }
 
     if (baselineEntries.count() != testEntries.count()) {
         SkDebugf("Baseline and test patterns do not yield corresponding number of files\n");
         return;
     }
 
     SkTaskGroup tg;
     SkTArray<SkThreadedDiff> runnableDiffs;
     runnableDiffs.reset(baselineEntries.count());
 

[mtklein, 2014/09/05 18:46:43]

Ooh, I see.  Try moving "SkTaskGroup tg;" down to just before the for loop, then
remove the call to tg.wait()?

runnableDiffs goes out of scope before tg, so it's deleted before we call
wait().

     for (int x = 0; x < baselineEntries.count(); x++) {
         runnableDiffs[x].setup(this, baselineEntries[x], testEntries[x]);
         tg.add(&runnableDiffs[x]);
     }
+    tg.wait();
 }
 
 void SkDiffContext::outputRecords(SkWStream& stream, bool useJSONP) {
     SkTLList<DiffRecord>::Iter iter(fRecords, SkTLList<DiffRecord>::Iter::kHead_IterStart);
     DiffRecord* currentRecord = iter.get();
 
     if (useJSONP) {
         stream.writeText("var SkPDiffRecords = {\n");
     } else {
         stream.writeText("{\n");
@@ skipping 149 matching lines @@
         for (int i = 0; i < cntColumns; i++) {
             SkString str;
             str.printf(", %f", values[i]);
             stream.writeText(str.c_str());
         }
         stream.writeText("\n");
 
         currentRecord = iter2.next();
     }
 }