Bug 1270814 - initialize pointers from LoopUnroller. r=jandem

MozReview-Commit-ID: H7u0inBzxmF

--HG--
extra : rebase_source : 0befa16b3701b8f52026a49f39f9aa7c69861482

js/src/jit/LoopUnroller.cpp

@@ -21,7 +21,10 @@ struct LoopUnroller
                     PointerHasher<MDefinition*, 2>, SystemAllocPolicy> DefinitionMap;
 
     explicit LoopUnroller(MIRGraph& graph)
-      : graph(graph), alloc(graph.alloc())
+      : graph(graph), alloc(graph.alloc()),
+        header(nullptr), backedge(nullptr),
+        unrolledHeader(nullptr), unrolledBackedge(nullptr),
+        oldPreheader(nullptr), newPreheader(nullptr)
     {}
 
     MIRGraph& graph;