CodeTracer should open file in binary mode to avoid line endings normalization.

src/isolate.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_ISOLATE_H_
 #define V8_ISOLATE_H_
 
 #include <queue>
 #include "include/v8-debug.h"
 #include "src/allocation.h"
@@ skipping 1543 matching lines @@
    private:
     CodeTracer* tracer_;
   };
 
   void OpenFile() {
     if (!ShouldRedirect()) {
       return;
     }
 
     if (file_ == NULL) {
-      file_ = base::OS::FOpen(filename_.start(), "a");
+      file_ = base::OS::FOpen(filename_.start(), "ab");
     }
 
     scope_depth_++;
   }
 
   void CloseFile() {
     if (!ShouldRedirect()) {
       return;
     }
 
@@ skipping 11 matching lines @@
   }
 
   EmbeddedVector<char, 128> filename_;
   FILE* file_;
   int scope_depth_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_ISOLATE_H_