--- a/js/xpconnect/src/XPCJSContext.cpp
+++ b/js/xpconnect/src/XPCJSContext.cpp
@@ -3653,66 +3653,66 @@ XPCJSContext::AfterProcessTask(uint32_t 
 
 /***************************************************************************/
 
 void
 XPCJSContext::DebugDump(int16_t depth)
 {
 #ifdef DEBUG
     depth--;
-    XPC_LOG_ALWAYS(("XPCJSContext @ %x", this));
+    XPC_LOG_ALWAYS(("XPCJSContext @ %p", this));
         XPC_LOG_INDENT();
-        XPC_LOG_ALWAYS(("mJSContext @ %x", Context()));
-
-        XPC_LOG_ALWAYS(("mWrappedJSClassMap @ %x with %d wrapperclasses(s)",
+        XPC_LOG_ALWAYS(("mJSContext @ %p", Context()));
+
+        XPC_LOG_ALWAYS(("mWrappedJSClassMap @ %p with %d wrapperclasses(s)",
                         mWrappedJSClassMap, mWrappedJSClassMap->Count()));
         // iterate wrappersclasses...
         if (depth && mWrappedJSClassMap->Count()) {
             XPC_LOG_INDENT();
             for (auto i = mWrappedJSClassMap->Iter(); !i.Done(); i.Next()) {
                 auto entry = static_cast<IID2WrappedJSClassMap::Entry*>(i.Get());
                 entry->value->DebugDump(depth);
             }
             XPC_LOG_OUTDENT();
         }
 
         // iterate wrappers...
-        XPC_LOG_ALWAYS(("mWrappedJSMap @ %x with %d wrappers(s)",
+        XPC_LOG_ALWAYS(("mWrappedJSMap @ %p with %d wrappers(s)",
                         mWrappedJSMap, mWrappedJSMap->Count()));
         if (depth && mWrappedJSMap->Count()) {
             XPC_LOG_INDENT();
             mWrappedJSMap->Dump(depth);
             XPC_LOG_OUTDENT();
         }
 
-        XPC_LOG_ALWAYS(("mIID2NativeInterfaceMap @ %x with %d interface(s)",
+        XPC_LOG_ALWAYS(("mIID2NativeInterfaceMap @ %p with %d interface(s)",
                         mIID2NativeInterfaceMap,
                         mIID2NativeInterfaceMap->Count()));
 
-        XPC_LOG_ALWAYS(("mClassInfo2NativeSetMap @ %x with %d sets(s)",
+        XPC_LOG_ALWAYS(("mClassInfo2NativeSetMap @ %p with %d sets(s)",
                         mClassInfo2NativeSetMap,
                         mClassInfo2NativeSetMap->Count()));
 
-        XPC_LOG_ALWAYS(("mThisTranslatorMap @ %x with %d translator(s)",
+        XPC_LOG_ALWAYS(("mThisTranslatorMap @ %p with %d translator(s)",
                         mThisTranslatorMap, mThisTranslatorMap->Count()));
 
-        XPC_LOG_ALWAYS(("mNativeSetMap @ %x with %d sets(s)",
+        XPC_LOG_ALWAYS(("mNativeSetMap @ %p with %d sets(s)",
                         mNativeSetMap, mNativeSetMap->Count()));
 
         // iterate sets...
         if (depth && mNativeSetMap->Count()) {
             XPC_LOG_INDENT();
             for (auto i = mNativeSetMap->Iter(); !i.Done(); i.Next()) {
                 auto entry = static_cast<NativeSetMap::Entry*>(i.Get());
                 entry->key_value->DebugDump(depth);
             }
             XPC_LOG_OUTDENT();
         }
 
-        XPC_LOG_ALWAYS(("mPendingResult of %x", mPendingResult));
+        XPC_LOG_ALWAYS(("mPendingResult of %" PRIx32, static_cast<uint32_t>(mPendingResult)));
 
         XPC_LOG_OUTDENT();
 #endif
 }
 
 /***************************************************************************/
 
 void

--- a/js/xpconnect/src/XPCLog.cpp
+++ b/js/xpconnect/src/XPCLog.cpp
@@ -3,17 +3,17 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 /* Debug Logging support. */
 
 #include "XPCLog.h"
 #include "mozilla/Logging.h"
-#include "prprf.h"
+#include "mozilla/Sprintf.h"
 #include "mozilla/mozalloc.h"
 #include <string.h>
 #include <stdarg.h>
 
 // this all only works for DEBUG...
 #ifdef DEBUG
 
 #define SPACE_COUNT     200
@@ -52,17 +52,17 @@ XPC_Log_Finish()
 
 void
 XPC_Log_print(const char* fmt, ...)
 {
     va_list ap;
     char line[LINE_LEN];
 
     va_start(ap, fmt);
-    PR_vsnprintf(line, sizeof(line)-1, fmt, ap);
+    VsprintfLiteral(line, fmt, ap);
     va_end(ap);
     if (g_Indent)
         PR_LogPrint("%s%s",g_Spaces+SPACE_COUNT-(INDENT_FACTOR*g_Indent),line);
     else
         PR_LogPrint("%s",line);
 }
 
 bool

--- a/js/xpconnect/src/XPCLog.h
+++ b/js/xpconnect/src/XPCLog.h
@@ -4,16 +4,17 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 /* Debug Logging support. */
 
 #ifndef xpclog_h___
 #define xpclog_h___
 
+#include "mozilla/Attributes.h"
 #include "mozilla/Logging.h"
 
 /*
  * This uses mozilla/Logging.h. The module name used here is 'xpclog'.
  * These environment settings should work...
  *
  * SET MOZ_LOG=xpclog:5
  * SET MOZ_LOG_FILE=logfile.txt
@@ -34,17 +35,17 @@
 #define XPC_LOG_FLUSH()         PR_LogFlush()
 #define XPC_LOG_INDENT()        XPC_Log_Indent()
 #define XPC_LOG_OUTDENT()       XPC_Log_Outdent()
 #define XPC_LOG_CLEAR_INDENT()  XPC_Log_Clear_Indent()
 #define XPC_LOG_FINISH()        XPC_Log_Finish()
 
 extern "C" {
 
-void   XPC_Log_print(const char* fmt, ...);
+void   XPC_Log_print(const char* fmt, ...) MOZ_FORMAT_PRINTF(1, 2);
 bool   XPC_Log_Check(int i);
 void   XPC_Log_Indent();
 void   XPC_Log_Outdent();
 void   XPC_Log_Clear_Indent();
 void   XPC_Log_Finish();
 
 } // extern "C"
 

--- a/js/xpconnect/src/XPCWrappedJS.cpp
+++ b/js/xpconnect/src/XPCWrappedJS.cpp
@@ -692,31 +692,31 @@ nsXPCWrappedJS::GetProperty(const nsAStr
 }
 
 /***************************************************************************/
 
 NS_IMETHODIMP
 nsXPCWrappedJS::DebugDump(int16_t depth)
 {
 #ifdef DEBUG
-    XPC_LOG_ALWAYS(("nsXPCWrappedJS @ %x with mRefCnt = %d", this, mRefCnt.get()));
+    XPC_LOG_ALWAYS(("nsXPCWrappedJS @ %p with mRefCnt = %" PRIuPTR, this, mRefCnt.get()));
         XPC_LOG_INDENT();
 
-        XPC_LOG_ALWAYS(("%s wrapper around JSObject @ %x", \
+        XPC_LOG_ALWAYS(("%s wrapper around JSObject @ %p",              \
                         IsRootWrapper() ? "ROOT":"non-root", mJSObj.get()));
         char* name;
         GetClass()->GetInterfaceInfo()->GetName(&name);
         XPC_LOG_ALWAYS(("interface name is %s", name));
         if (name)
             free(name);
         char * iid = GetClass()->GetIID().ToString();
         XPC_LOG_ALWAYS(("IID number is %s", iid ? iid : "invalid"));
         if (iid)
             free(iid);
-        XPC_LOG_ALWAYS(("nsXPCWrappedJSClass @ %x", mClass.get()));
+        XPC_LOG_ALWAYS(("nsXPCWrappedJSClass @ %p", mClass.get()));
 
         if (!IsRootWrapper())
             XPC_LOG_OUTDENT();
         if (mNext) {
             if (IsRootWrapper()) {
                 XPC_LOG_ALWAYS(("Additional wrappers for this object..."));
                 XPC_LOG_INDENT();
             }

--- a/js/xpconnect/src/XPCWrappedJSClass.cpp
+++ b/js/xpconnect/src/XPCWrappedJSClass.cpp
@@ -1409,43 +1409,43 @@ xpc::NewOutObject(JSContext* cx)
 }
 
 
 NS_IMETHODIMP
 nsXPCWrappedJSClass::DebugDump(int16_t depth)
 {
 #ifdef DEBUG
     depth-- ;
-    XPC_LOG_ALWAYS(("nsXPCWrappedJSClass @ %x with mRefCnt = %d", this, mRefCnt.get()));
+    XPC_LOG_ALWAYS(("nsXPCWrappedJSClass @ %p with mRefCnt = %" PRIuPTR, this, mRefCnt.get()));
     XPC_LOG_INDENT();
         char* name;
         mInfo->GetName(&name);
         XPC_LOG_ALWAYS(("interface name is %s", name));
         if (name)
             free(name);
         char * iid = mIID.ToString();
         XPC_LOG_ALWAYS(("IID number is %s", iid ? iid : "invalid"));
         if (iid)
             free(iid);
-        XPC_LOG_ALWAYS(("InterfaceInfo @ %x", mInfo.get()));
+        XPC_LOG_ALWAYS(("InterfaceInfo @ %p", mInfo.get()));
         uint16_t methodCount = 0;
         if (depth) {
             uint16_t i;
             nsCOMPtr<nsIInterfaceInfo> parent;
             XPC_LOG_INDENT();
             mInfo->GetParent(getter_AddRefs(parent));
-            XPC_LOG_ALWAYS(("parent @ %x", parent.get()));
+            XPC_LOG_ALWAYS(("parent @ %p", parent.get()));
             mInfo->GetMethodCount(&methodCount);
             XPC_LOG_ALWAYS(("MethodCount = %d", methodCount));
             mInfo->GetConstantCount(&i);
             XPC_LOG_ALWAYS(("ConstantCount = %d", i));
             XPC_LOG_OUTDENT();
         }
-        XPC_LOG_ALWAYS(("mContext @ %x", mContext));
-        XPC_LOG_ALWAYS(("mDescriptors @ %x count = %d", mDescriptors, methodCount));
+        XPC_LOG_ALWAYS(("mContext @ %p", mContext));
+        XPC_LOG_ALWAYS(("mDescriptors @ %p count = %d", mDescriptors, methodCount));
         if (depth && mDescriptors && methodCount) {
             depth--;
             XPC_LOG_INDENT();
             for (uint16_t i = 0; i < methodCount; i++) {
                 XPC_LOG_ALWAYS(("Method %d is %s%s", \
                                 i, IsReflectable(i) ? "":" NOT ","reflectable"));
             }
             XPC_LOG_OUTDENT();

--- a/js/xpconnect/src/XPCWrappedNative.cpp
+++ b/js/xpconnect/src/XPCWrappedNative.cpp
@@ -2089,41 +2089,41 @@ XPCWrappedNative::HasNativeMember(Handle
     uint16_t ignored;
     return GetSet()->FindMember(name, &member, &ignored) && !!member;
 }
 
 NS_IMETHODIMP XPCWrappedNative::DebugDump(int16_t depth)
 {
 #ifdef DEBUG
     depth-- ;
-    XPC_LOG_ALWAYS(("XPCWrappedNative @ %x with mRefCnt = %d", this, mRefCnt.get()));
+    XPC_LOG_ALWAYS(("XPCWrappedNative @ %p with mRefCnt = %" PRIuPTR, this, mRefCnt.get()));
     XPC_LOG_INDENT();
 
         if (HasProto()) {
             XPCWrappedNativeProto* proto = GetProto();
             if (depth && proto)
                 proto->DebugDump(depth);
             else
-                XPC_LOG_ALWAYS(("mMaybeProto @ %x", proto));
+                XPC_LOG_ALWAYS(("mMaybeProto @ %p", proto));
         } else
-            XPC_LOG_ALWAYS(("Scope @ %x", GetScope()));
+            XPC_LOG_ALWAYS(("Scope @ %p", GetScope()));
 
         if (depth && mSet)
             mSet->DebugDump(depth);
         else
-            XPC_LOG_ALWAYS(("mSet @ %x", mSet.get()));
+            XPC_LOG_ALWAYS(("mSet @ %p", mSet.get()));
 
-        XPC_LOG_ALWAYS(("mFlatJSObject of %x", mFlatJSObject.unbarrieredGetPtr()));
-        XPC_LOG_ALWAYS(("mIdentity of %x", mIdentity.get()));
-        XPC_LOG_ALWAYS(("mScriptable @ %x", mScriptable.get()));
+        XPC_LOG_ALWAYS(("mFlatJSObject of %p", mFlatJSObject.unbarrieredGetPtr()));
+        XPC_LOG_ALWAYS(("mIdentity of %p", mIdentity.get()));
+        XPC_LOG_ALWAYS(("mScriptable @ %p", mScriptable.get()));
 
         if (depth && mScriptable) {
             XPC_LOG_INDENT();
             XPC_LOG_ALWAYS(("mFlags of %x", mScriptable->GetScriptableFlags()));
-            XPC_LOG_ALWAYS(("mJSClass @ %x", mScriptable->GetJSClass()));
+            XPC_LOG_ALWAYS(("mJSClass @ %p", mScriptable->GetJSClass()));
             XPC_LOG_OUTDENT();
         }
     XPC_LOG_OUTDENT();
 #endif
     return NS_OK;
 }
 
 /***************************************************************************/

--- a/js/xpconnect/src/XPCWrappedNativeInfo.cpp
+++ b/js/xpconnect/src/XPCWrappedNativeInfo.cpp
@@ -409,21 +409,21 @@ XPCNativeInterface::SizeOfIncludingThis(
     return mallocSizeOf(this);
 }
 
 void
 XPCNativeInterface::DebugDump(int16_t depth)
 {
 #ifdef DEBUG
     depth--;
-    XPC_LOG_ALWAYS(("XPCNativeInterface @ %x", this));
+    XPC_LOG_ALWAYS(("XPCNativeInterface @ %p", this));
         XPC_LOG_INDENT();
         XPC_LOG_ALWAYS(("name is %s", GetNameString()));
         XPC_LOG_ALWAYS(("mMemberCount is %d", mMemberCount));
-        XPC_LOG_ALWAYS(("mInfo @ %x", mInfo.get()));
+        XPC_LOG_ALWAYS(("mInfo @ %p", mInfo.get()));
         XPC_LOG_OUTDENT();
 #endif
 }
 
 /***************************************************************************/
 // XPCNativeSetKey
 
 static PLDHashNumber
@@ -782,17 +782,17 @@ XPCNativeSet::SizeOfIncludingThis(Malloc
     return mallocSizeOf(this);
 }
 
 void
 XPCNativeSet::DebugDump(int16_t depth)
 {
 #ifdef DEBUG
     depth--;
-    XPC_LOG_ALWAYS(("XPCNativeSet @ %x", this));
+    XPC_LOG_ALWAYS(("XPCNativeSet @ %p", this));
         XPC_LOG_INDENT();
 
         XPC_LOG_ALWAYS(("mInterfaceCount of %d", mInterfaceCount));
         if (depth) {
             for (uint16_t i = 0; i < mInterfaceCount; i++)
                 mInterfaces[i]->DebugDump(depth);
         }
         XPC_LOG_ALWAYS(("mMemberCount of %d", mMemberCount));

--- a/js/xpconnect/src/XPCWrappedNativeProto.cpp
+++ b/js/xpconnect/src/XPCWrappedNativeProto.cpp
@@ -168,26 +168,26 @@ XPCWrappedNativeProto::GetNewOrUsed(XPCW
     return proto;
 }
 
 void
 XPCWrappedNativeProto::DebugDump(int16_t depth)
 {
 #ifdef DEBUG
     depth-- ;
-    XPC_LOG_ALWAYS(("XPCWrappedNativeProto @ %x", this));
+    XPC_LOG_ALWAYS(("XPCWrappedNativeProto @ %p", this));
     XPC_LOG_INDENT();
         XPC_LOG_ALWAYS(("gDEBUG_LiveProtoCount is %d", gDEBUG_LiveProtoCount));
-        XPC_LOG_ALWAYS(("mScope @ %x", mScope));
-        XPC_LOG_ALWAYS(("mJSProtoObject @ %x", mJSProtoObject.get()));
-        XPC_LOG_ALWAYS(("mSet @ %x", mSet.get()));
-        XPC_LOG_ALWAYS(("mScriptable @ %x", mScriptable.get()));
+        XPC_LOG_ALWAYS(("mScope @ %p", mScope));
+        XPC_LOG_ALWAYS(("mJSProtoObject @ %p", mJSProtoObject.get()));
+        XPC_LOG_ALWAYS(("mSet @ %p", mSet.get()));
+        XPC_LOG_ALWAYS(("mScriptable @ %p", mScriptable.get()));
         if (depth && mScriptable) {
             XPC_LOG_INDENT();
             XPC_LOG_ALWAYS(("mFlags of %x", mScriptable->GetScriptableFlags()));
-            XPC_LOG_ALWAYS(("mJSClass @ %x", mScriptable->GetJSClass()));
+            XPC_LOG_ALWAYS(("mJSClass @ %p", mScriptable->GetJSClass()));
             XPC_LOG_OUTDENT();
         }
     XPC_LOG_OUTDENT();
 #endif
 }
 
 

--- a/js/xpconnect/src/XPCWrappedNativeScope.cpp
+++ b/js/xpconnect/src/XPCWrappedNativeScope.cpp
@@ -854,48 +854,48 @@ XPCWrappedNativeScope::DebugDumpAllScope
     // get scope count.
     int count = 0;
     XPCWrappedNativeScope* cur;
     for (cur = gScopes; cur; cur = cur->mNext)
         count++ ;
 
     XPC_LOG_ALWAYS(("chain of %d XPCWrappedNativeScope(s)", count));
     XPC_LOG_INDENT();
-        XPC_LOG_ALWAYS(("gDyingScopes @ %x", gDyingScopes));
+        XPC_LOG_ALWAYS(("gDyingScopes @ %p", gDyingScopes));
         if (depth)
             for (cur = gScopes; cur; cur = cur->mNext)
                 cur->DebugDump(depth);
     XPC_LOG_OUTDENT();
 #endif
 }
 
 void
 XPCWrappedNativeScope::DebugDump(int16_t depth)
 {
 #ifdef DEBUG
     depth-- ;
-    XPC_LOG_ALWAYS(("XPCWrappedNativeScope @ %x", this));
+    XPC_LOG_ALWAYS(("XPCWrappedNativeScope @ %p", this));
     XPC_LOG_INDENT();
-        XPC_LOG_ALWAYS(("mNext @ %x", mNext));
-        XPC_LOG_ALWAYS(("mComponents @ %x", mComponents.get()));
-        XPC_LOG_ALWAYS(("mGlobalJSObject @ %x", mGlobalJSObject.get()));
+        XPC_LOG_ALWAYS(("mNext @ %p", mNext));
+        XPC_LOG_ALWAYS(("mComponents @ %p", mComponents.get()));
+        XPC_LOG_ALWAYS(("mGlobalJSObject @ %p", mGlobalJSObject.get()));
 
-        XPC_LOG_ALWAYS(("mWrappedNativeMap @ %x with %d wrappers(s)",
+        XPC_LOG_ALWAYS(("mWrappedNativeMap @ %p with %d wrappers(s)",
                         mWrappedNativeMap, mWrappedNativeMap->Count()));
         // iterate contexts...
         if (depth && mWrappedNativeMap->Count()) {
             XPC_LOG_INDENT();
             for (auto i = mWrappedNativeMap->Iter(); !i.Done(); i.Next()) {
                 auto entry = static_cast<Native2WrappedNativeMap::Entry*>(i.Get());
                 entry->value->DebugDump(depth);
             }
             XPC_LOG_OUTDENT();
         }
 
-        XPC_LOG_ALWAYS(("mWrappedNativeProtoMap @ %x with %d protos(s)",
+        XPC_LOG_ALWAYS(("mWrappedNativeProtoMap @ %p with %d protos(s)",
                         mWrappedNativeProtoMap,
                         mWrappedNativeProtoMap->Count()));
         // iterate contexts...
         if (depth && mWrappedNativeProtoMap->Count()) {
             XPC_LOG_INDENT();
             for (auto i = mWrappedNativeProtoMap->Iter(); !i.Done(); i.Next()) {
                 auto entry = static_cast<ClassInfo2WrappedNativeProtoMap::Entry*>(i.Get());
                 entry->value->DebugDump(depth);

--- a/js/xpconnect/src/nsXPConnect.cpp
+++ b/js/xpconnect/src/nsXPConnect.cpp
@@ -927,25 +927,25 @@ nsXPConnect::GetWrappedNativePrototype(J
     return NS_OK;
 }
 
 NS_IMETHODIMP
 nsXPConnect::DebugDump(int16_t depth)
 {
 #ifdef DEBUG
     depth-- ;
-    XPC_LOG_ALWAYS(("nsXPConnect @ %x with mRefCnt = %d", this, mRefCnt.get()));
+    XPC_LOG_ALWAYS(("nsXPConnect @ %p with mRefCnt = %" PRIuPTR, this, mRefCnt.get()));
     XPC_LOG_INDENT();
-        XPC_LOG_ALWAYS(("gSelf @ %x", gSelf));
+        XPC_LOG_ALWAYS(("gSelf @ %p", gSelf));
         XPC_LOG_ALWAYS(("gOnceAliveNowDead is %d", (int)gOnceAliveNowDead));
         if (mContext) {
             if (depth)
                 mContext->DebugDump(depth);
             else
-                XPC_LOG_ALWAYS(("XPCJSContext @ %x", mContext));
+                XPC_LOG_ALWAYS(("XPCJSContext @ %p", mContext));
         } else
             XPC_LOG_ALWAYS(("mContext is null"));
         XPCWrappedNativeScope::DebugDumpAllScopes(depth);
     XPC_LOG_OUTDENT();
 #endif
     return NS_OK;
 }
 
@@ -977,17 +977,17 @@ nsXPConnect::DebugDumpObject(nsISupports
                                               getter_AddRefs(wn)))) {
         XPC_LOG_ALWAYS(("Dumping a nsIXPConnectWrappedNative..."));
         wn->DebugDump(depth);
     } else if (NS_SUCCEEDED(p->QueryInterface(NS_GET_IID(nsIXPConnectWrappedJS),
                                               getter_AddRefs(wjs)))) {
         XPC_LOG_ALWAYS(("Dumping a nsIXPConnectWrappedJS..."));
         wjs->DebugDump(depth);
     } else {
-        XPC_LOG_ALWAYS(("*** Could not dump the nsISupports @ %x", p));
+        XPC_LOG_ALWAYS(("*** Could not dump the nsISupports @ %p", p));
     }
 #endif
     return NS_OK;
 }
 
 NS_IMETHODIMP
 nsXPConnect::DebugDumpJSStack(bool showArgs,
                               bool showLocals,