Don't use the size-zero array hack to access variable data in Snapshot.

runtime/vm/snapshot.h

Index: runtime/vm/snapshot.h
diff --git a/runtime/vm/snapshot.h b/runtime/vm/snapshot.h
index 82e689f17ada97e9e9267bb2af51af8b39e004d1..300babba53348264966d49bcfb4fcfe9ac8c511a 100644
--- a/runtime/vm/snapshot.h
+++ b/runtime/vm/snapshot.h
@@ -145,7 +145,6 @@ class Snapshot {
   static const Snapshot* SetupFromBuffer(const void* raw_memory);
 
   // Getters.
-  const uint8_t* content() const { return content_; }
   intptr_t length() const {
     return static_cast<intptr_t>(ReadUnaligned(&unaligned_length_));
   }
@@ -172,8 +171,12 @@ class Snapshot {
   // The following fields are potentially unaligned.
   int64_t unaligned_length_;  // Stream length.
   int64_t unaligned_kind_;  // Kind of snapshot.
-  uint8_t content_[];  // Stream content.
 
+ public:
+  // Variable length data follows here.
+  const uint8_t* content() const { OPEN_ARRAY_START(uint8_t, uint8_t); }

[siva, 2014/09/24 22:02:53]

Why not move this block to the top above the 'private:' stuff?

[rmacnak, 2014/09/24 22:38:08]

The intention was for content() to appear in the position the data occupies on
the object, a la raw_object.h. Leaving content() private and marking users as
friends as discussed offline doesn't work because one of the users in an API
function and friend doesn't play well with DART_EXPORT. Moving content() back to
the public block.

+
+ private:
   DISALLOW_COPY_AND_ASSIGN(Snapshot);
 };