diff --git a/docshell/base/nsDocShell.cpp b/docshell/base/nsDocShell.cpp
index 3301fd14c8cb..05601db40470 100644
--- a/docshell/base/nsDocShell.cpp
+++ b/docshell/base/nsDocShell.cpp
@@ -161,6 +161,7 @@
 #include "nsIJARChannel.h"
 
 #include "prlog.h"
+#include "prmem.h"
 
 #include "nsISelectionDisplay.h"
 
diff --git a/dom/base/nsGlobalWindow.cpp b/dom/base/nsGlobalWindow.cpp
index 2716ace3ca22..f2f4977f01ed 100644
--- a/dom/base/nsGlobalWindow.cpp
+++ b/dom/base/nsGlobalWindow.cpp
@@ -32,6 +32,7 @@
 // Helper Classes
 #include "nsXPIDLString.h"
 #include "nsJSUtils.h"
+#include "prmem.h"
 #include "jsapi.h"              // for JSAutoRequest
 #include "jsdbgapi.h"           // for JS_ClearWatchPointsForObject
 #include "jsfriendapi.h"        // for JS_GetGlobalForFrame
diff --git a/dom/base/nsJSEnvironment.cpp b/dom/base/nsJSEnvironment.cpp
index b35b9a522526..24543dca21ba 100644
--- a/dom/base/nsJSEnvironment.cpp
+++ b/dom/base/nsJSEnvironment.cpp
@@ -49,6 +49,7 @@
 #include "nsIObjectInputStream.h"
 #include "nsIObjectOutputStream.h"
 #include "nsDOMScriptObjectHolder.h"
+#include "prmem.h"
 #include "WrapperFactory.h"
 #include "nsGlobalWindow.h"
 #include "nsScriptNameSpaceManager.h"
@@ -4105,18 +4106,24 @@ public:
 
 protected:
   JSContext *mContext;
-  FallibleTArray<jsval> mArgv;
+  jsval *mArgv;
+  uint32_t mArgc;
 };
 
 nsJSArgArray::nsJSArgArray(JSContext *aContext, uint32_t argc, jsval *argv,
                            nsresult *prv) :
-    mContext(aContext)
+    mContext(aContext),
+    mArgv(nullptr),
+    mArgc(argc)
 {
   // copy the array - we don't know its lifetime, and ours is tied to xpcom
   // refcounting.  Alloc zero'd array so cleanup etc is safe.
-  if (!mArgv.EnsureLengthAtLeast(argc)) {
-    *prv = NS_ERROR_OUT_OF_MEMORY;
-    return;
+  if (argc) {
+    mArgv = (jsval *) PR_CALLOC(argc * sizeof(jsval));
+    if (!mArgv) {
+      *prv = NS_ERROR_OUT_OF_MEMORY;
+      return;
+    }
   }
 
   // Callers are allowed to pass in a null argv even for argc > 0. They can
@@ -4141,10 +4148,13 @@ nsJSArgArray::~nsJSArgArray()
 void
 nsJSArgArray::ReleaseJSObjects()
 {
-  if (!mArgv.IsEmpty())
+  if (mArgv) {
+    PR_DELETE(mArgv);
+  }
+  if (mArgc > 0) {
+    mArgc = 0;
     NS_DROP_JS_OBJECTS(this, nsJSArgArray);
-
-  mArgv.Clear();
+  }
 }
 
 // QueryInterface implementation for nsJSArgArray
@@ -4157,10 +4167,12 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsJSArgArray)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
 
 NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(nsJSArgArray)
-  uint32_t length = tmp->mArgv.Length();
-  for (uint32_t i = 0; i < length; i++) {
-      if (JSVAL_IS_GCTHING(tmp->mArgv[i])) {
-        NS_IMPL_CYCLE_COLLECTION_TRACE_JS_CALLBACK(JSVAL_TO_GCTHING(tmp->mArgv[i]),
+  jsval *argv = tmp->mArgv;
+  if (argv) {
+    jsval *end;
+    for (end = argv + tmp->mArgc; argv < end; ++argv) {
+      if (JSVAL_IS_GCTHING(*argv))
+        NS_IMPL_CYCLE_COLLECTION_TRACE_JS_CALLBACK(JSVAL_TO_GCTHING(*argv),
                                                    "mArgv[i]")
     }
   }
@@ -4178,15 +4190,15 @@ NS_IMPL_CYCLE_COLLECTING_RELEASE(nsJSArgArray)
 nsresult
 nsJSArgArray::GetArgs(uint32_t *argc, void **argv)
 {
-  *argv = (void *)mArgv.Elements();
-  *argc = mArgv.Length();
+  *argv = (void *)mArgv;
+  *argc = mArgc;
   return NS_OK;
 }
 
 // nsIArray impl
 NS_IMETHODIMP nsJSArgArray::GetLength(uint32_t *aLength)
 {
-  *aLength = mArgv.Length();
+  *aLength = mArgc;
   return NS_OK;
 }
 
@@ -4194,7 +4206,7 @@ NS_IMETHODIMP nsJSArgArray::GetLength(uint32_t *aLength)
 NS_IMETHODIMP nsJSArgArray::QueryElementAt(uint32_t index, const nsIID & uuid, void * *result)
 {
   *result = nullptr;
-  if (index >= mArgv.Length())
+  if (index >= mArgc)
     return NS_ERROR_INVALID_ARG;
 
   if (uuid.Equals(NS_GET_IID(nsIVariant)) || uuid.Equals(NS_GET_IID(nsISupports))) {
diff --git a/dom/file/ArchiveZipEvent.cpp b/dom/file/ArchiveZipEvent.cpp
index 4ddfbeef755b..d9cb8c9b58f7 100644
--- a/dom/file/ArchiveZipEvent.cpp
+++ b/dom/file/ArchiveZipEvent.cpp
@@ -191,7 +191,7 @@ ArchiveReaderZipEvent::Exec()
     }
 
     // Read the name:
-    nsAutoArrayPtr<char> filename(new char[filenameLen + 1]);
+    char* filename = (char*)PR_Malloc(filenameLen + 1);
     rv = inputStream->Read(filename, filenameLen, &ret);
     if (NS_FAILED(rv) || ret != filenameLen) {
       return RunShare(NS_ERROR_UNEXPECTED);
@@ -204,6 +204,8 @@ ArchiveReaderZipEvent::Exec()
       mFileList.AppendElement(new ArchiveZipItem(filename, centralStruct, mOptions));
     }
 
+    PR_Free(filename);
+
     // Ignore the rest
     seekableStream->Seek(nsISeekableStream::NS_SEEK_CUR, extraLen + commentLen);
   }
diff --git a/dom/plugins/base/nsPluginDirServiceProvider.cpp b/dom/plugins/base/nsPluginDirServiceProvider.cpp
index b7e9c006b72c..6a205f6e7726 100644
--- a/dom/plugins/base/nsPluginDirServiceProvider.cpp
+++ b/dom/plugins/base/nsPluginDirServiceProvider.cpp
@@ -8,6 +8,7 @@
 #include "nsCRT.h"
 #include "nsIFile.h"
 #include "nsDependentString.h"
+#include "prmem.h"
 #include "nsArrayEnumerator.h"
 #include "mozilla/Preferences.h"