Bug 963528 - Don't allocate zero-sized script data. r=luke.

--HG--
extra : rebase_source : 16beebadc53671e68b73d920ad96c366f48206d3

js/src/jsscript.cpp

@@ -163,7 +163,8 @@ Bindings::switchToScriptStorage(Binding *newBindingArray)
     JS_ASSERT(bindingArrayUsingTemporaryStorage());
     JS_ASSERT(!(uintptr_t(newBindingArray) & TEMPORARY_STORAGE_BIT));
 
-    PodCopy(newBindingArray, bindingArray(), count());
+    if (count() > 0)
+        PodCopy(newBindingArray, bindingArray(), count());
     bindingArrayAndFlag_ = uintptr_t(newBindingArray);
     return reinterpret_cast<uint8_t *>(newBindingArray + count());
 }
@@ -1947,9 +1948,13 @@ JSScript::partiallyInit(ExclusiveContext *cx, HandleScript script, uint32_t ncon
 {
     size_t size = ScriptDataSize(script->bindings.count(), nconsts, nobjects, nregexps, ntrynotes,
                                  nblockscopes);
-    script->data = AllocScriptData(cx, size);
-    if (!script->data)
-        return false;
+    if (size > 0) {
+        script->data = AllocScriptData(cx, size);
+        if (!script->data)
+            return false;
+    } else {
+        script->data = nullptr;
+    }
     script->dataSize_ = size;
 
     JS_ASSERT(nTypeSets <= UINT16_MAX);