diff --git a/expat/lib/xmlparse.c b/expat/lib/xmlparse.c
--- a/expat/lib/xmlparse.c
+++ b/expat/lib/xmlparse.c
@@ -456,24 +456,36 @@ typedef unsigned long long XmlBigCount;
 typedef struct accounting {
   XmlBigCount countBytesDirect;
   XmlBigCount countBytesIndirect;
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
   unsigned long debugLevel;
+#endif
+/* END MOZILLA CHANGE */
   float maximumAmplificationFactor; // >=1.0
   unsigned long long activationThresholdBytes;
 } ACCOUNTING;
 
 typedef struct MALLOC_TRACKER {
   XmlBigCount bytesAllocated;
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#  if 0
   XmlBigCount peakBytesAllocated; // updated live only for debug level >=2
   unsigned long debugLevel;
+#endif
+/* END MOZILLA CHANGE */
   float maximumAmplificationFactor; // >=1.0
   XmlBigCount activationThresholdBytes;
 } MALLOC_TRACKER;
 
 typedef struct entity_stats {
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
   unsigned int countEverOpened;
   unsigned int currentDepth;
   unsigned int maximumDepthSeen;
   unsigned long debugLevel;
+#endif
+/* END MOZILLA CHANGE */
 } ENTITY_STATS;
 #endif /* XML_GE == 1 */
 
@@ -632,18 +644,26 @@ static void parserInit(XML_Parser parser, const XML_Char *encodingName);
 static float accountingGetCurrentAmplification(XML_Parser rootParser);
 static void accountingReportStats(XML_Parser originParser, const char *epilog);
 static void accountingOnAbort(XML_Parser originParser);
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
 static void accountingReportDiff(XML_Parser rootParser,
                                  unsigned int levelsAwayFromRootParser,
                                  const char *before, const char *after,
                                  ptrdiff_t bytesMore, int source_line,
                                  enum XML_Account account);
+#endif
+/* END MOZILLA CHANGE */
 static XML_Bool accountingDiffTolerated(XML_Parser originParser, int tok,
                                         const char *before, const char *after,
                                         int source_line,
                                         enum XML_Account account);
 
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
 static void entityTrackingReportStats(XML_Parser parser, ENTITY *entity,
                                       const char *action, int sourceLine);
+#endif
+/* END MOZILLA CHANGE */
 static void entityTrackingOnOpen(XML_Parser parser, ENTITY *entity,
                                  int sourceLine);
 static void entityTrackingOnClose(XML_Parser parser, ENTITY *entity,
@@ -653,8 +673,12 @@ static void entityTrackingOnClose(XML_Parser parser, ENTITY *entity,
 static XML_Parser getRootParserOf(XML_Parser parser,
                                   unsigned int *outLevelDiff);
 
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
 static unsigned long getDebugLevel(const char *variableName,
                                    unsigned long defaultDebugLevel);
+#endif
+/* END MOZILLA CHANGE */
 
 #define poolStart(pool) ((pool)->start)
 #define poolLength(pool) ((pool)->ptr - (pool)->start)
@@ -814,6 +838,8 @@ struct XML_ParserStruct {
 #endif
 
 #if XML_GE == 1
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
 static void
 expat_heap_stat(XML_Parser rootParser, char operator, XmlBigCount absDiff,
                 XmlBigCount newTotal, XmlBigCount peakTotal, int sourceLine) {
@@ -827,6 +853,8 @@ expat_heap_stat(XML_Parser rootParser, char operator, XmlBigCount absDiff,
       (void *)rootParser, rootParser->m_accounting.countBytesDirect, operator,
       absDiff, newTotal, peakTotal, (double)amplification, sourceLine);
 }
+#endif
+/* END MOZILLA CHANGE */
 
 static bool
 expat_heap_increase_tolerable(XML_Parser rootParser, XmlBigCount increase,
@@ -855,9 +883,13 @@ expat_heap_increase_tolerable(XML_Parser rootParser, XmlBigCount increase,
     }
   }
 
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
   if (! tolerable && (rootParser->m_alloc_tracker.debugLevel >= 1)) {
     expat_heap_stat(rootParser, '+', increase, newTotal, newTotal, sourceLine);
   }
+#endif
+/* END MOZILLA CHANGE */
 
   return tolerable;
 }
@@ -901,6 +933,8 @@ expat_malloc(XML_Parser parser, size_t size, int sourceLine) {
   // Update accounting
   rootParser->m_alloc_tracker.bytesAllocated += bytesToAllocate;
 
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
   // Report as needed
   if (rootParser->m_alloc_tracker.debugLevel >= 2) {
     if (rootParser->m_alloc_tracker.bytesAllocated
@@ -912,6 +946,8 @@ expat_malloc(XML_Parser parser, size_t size, int sourceLine) {
                     rootParser->m_alloc_tracker.bytesAllocated,
                     rootParser->m_alloc_tracker.peakBytesAllocated, sourceLine);
   }
+#endif
+/* END MOZILLA CHANGE */
 
   return (char *)mallocedPtr + sizeof(size_t) + EXPAT_MALLOC_PADDING;
 }
@@ -941,12 +977,16 @@ expat_free(XML_Parser parser, void *ptr, int sourceLine) {
   assert(rootParser->m_alloc_tracker.bytesAllocated >= bytesAllocated);
   rootParser->m_alloc_tracker.bytesAllocated -= bytesAllocated;
 
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
   // Report as needed
   if (rootParser->m_alloc_tracker.debugLevel >= 2) {
     expat_heap_stat(rootParser, '-', bytesAllocated,
                     rootParser->m_alloc_tracker.bytesAllocated,
                     rootParser->m_alloc_tracker.peakBytesAllocated, sourceLine);
   }
+#endif
+/* END MOZILLA CHANGE */
 
   // NOTE: This may be freeing rootParser, so freeing has to come last
   parser->m_mem.free_fcn(mallocedPtr);
@@ -1011,6 +1051,8 @@ expat_realloc(XML_Parser parser, void *ptr, size_t size, int sourceLine) {
     rootParser->m_alloc_tracker.bytesAllocated -= absDiff;
   }
 
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
   // Report as needed
   if (rootParser->m_alloc_tracker.debugLevel >= 2) {
     if (rootParser->m_alloc_tracker.bytesAllocated
@@ -1022,6 +1064,8 @@ expat_realloc(XML_Parser parser, void *ptr, size_t size, int sourceLine) {
                     rootParser->m_alloc_tracker.bytesAllocated,
                     rootParser->m_alloc_tracker.peakBytesAllocated, sourceLine);
   }
+#endif
+/* END MOZILLA CHANGE */
 
   // Update in-block recorded size
   *(size_t *)mallocedPtr = size;
@@ -1431,8 +1475,12 @@ parserCreate(const XML_Char *encodingName,
   // Initialize .m_alloc_tracker
   memset(&parser->m_alloc_tracker, 0, sizeof(MALLOC_TRACKER));
   if (parentParser == NULL) {
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
     parser->m_alloc_tracker.debugLevel
         = getDebugLevel("EXPAT_MALLOC_DEBUG", 0u);
+#endif
+/* END MOZILLA CHANGE */
     parser->m_alloc_tracker.maximumAmplificationFactor
         = EXPAT_ALLOC_TRACKER_MAXIMUM_AMPLIFICATION_DEFAULT;
     parser->m_alloc_tracker.activationThresholdBytes
@@ -1452,6 +1500,8 @@ parserCreate(const XML_Char *encodingName,
   assert(SIZE_MAX - rootParser->m_alloc_tracker.bytesAllocated >= increase);
   rootParser->m_alloc_tracker.bytesAllocated += increase;
 
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
   // Report on allocation
   if (rootParser->m_alloc_tracker.debugLevel >= 2) {
     if (rootParser->m_alloc_tracker.bytesAllocated
@@ -1464,6 +1514,8 @@ parserCreate(const XML_Char *encodingName,
                     rootParser->m_alloc_tracker.bytesAllocated,
                     rootParser->m_alloc_tracker.peakBytesAllocated, __LINE__);
   }
+#endif
+/* END MOZILLA CHANGE */
 #else
   parser->m_parentParser = NULL;
 #endif // XML_GE == 1
@@ -1644,15 +1696,23 @@ parserInit(XML_Parser parser, const XML_Char *encodingName) {
 
 #if XML_GE == 1
   memset(&parser->m_accounting, 0, sizeof(ACCOUNTING));
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
   parser->m_accounting.debugLevel = getDebugLevel("EXPAT_ACCOUNTING_DEBUG", 0u);
+#endif
+/* END MOZILLA CHANGE */
   parser->m_accounting.maximumAmplificationFactor
       = EXPAT_BILLION_LAUGHS_ATTACK_PROTECTION_MAXIMUM_AMPLIFICATION_DEFAULT;
   parser->m_accounting.activationThresholdBytes
       = EXPAT_BILLION_LAUGHS_ATTACK_PROTECTION_ACTIVATION_THRESHOLD_DEFAULT;
 
   memset(&parser->m_entity_stats, 0, sizeof(ENTITY_STATS));
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
   parser->m_entity_stats.debugLevel = getDebugLevel("EXPAT_ENTITY_DEBUG", 0u);
 #endif
+/* END MOZILLA CHANGE */
+#endif
 }
 
 /* moves list of bindings to m_freeBindingList */
@@ -8667,6 +8727,8 @@ accountingGetCurrentAmplification(XML_Parser rootParser) {
 
 static void
 accountingReportStats(XML_Parser originParser, const char *epilog) {
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
   const XML_Parser rootParser = getRootParserOf(originParser, NULL);
   assert(! rootParser->m_parentParser);
 
@@ -8682,6 +8744,8 @@ accountingReportStats(XML_Parser originParser, const char *epilog) {
           (void *)rootParser, rootParser->m_accounting.countBytesDirect,
           rootParser->m_accounting.countBytesIndirect,
           (double)amplificationFactor, epilog);
+#endif
+/* END MOZILLA CHANGE */
 }
 
 static void
@@ -8689,6 +8753,8 @@ accountingOnAbort(XML_Parser originParser) {
   accountingReportStats(originParser, " ABORTING\n");
 }
 
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
 static void
 accountingReportDiff(XML_Parser rootParser,
                      unsigned int levelsAwayFromRootParser, const char *before,
@@ -8725,6 +8791,8 @@ accountingReportDiff(XML_Parser rootParser,
   }
   fprintf(stderr, "\"\n");
 }
+#endif
+/* END MOZILLA CHANGE */
 
 static XML_Bool
 accountingDiffTolerated(XML_Parser originParser, int tok, const char *before,
@@ -8772,11 +8840,15 @@ accountingDiffTolerated(XML_Parser originParser, int tok, const char *before,
         || (amplificationFactor
             <= rootParser->m_accounting.maximumAmplificationFactor);
 
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
   if (rootParser->m_accounting.debugLevel >= 2u) {
     accountingReportStats(rootParser, "");
     accountingReportDiff(rootParser, levelsAwayFromRootParser, before, after,
                          bytesMore, source_line, account);
   }
+#endif
+/* END MOZILLA CHANGE */
 
   return tolerated;
 }
@@ -8795,6 +8867,8 @@ testingAccountingGetCountBytesIndirect(XML_Parser parser) {
   return parser->m_accounting.countBytesIndirect;
 }
 
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
 static void
 entityTrackingReportStats(XML_Parser rootParser, ENTITY *entity,
                           const char *action, int sourceLine) {
@@ -8818,9 +8892,13 @@ entityTrackingReportStats(XML_Parser rootParser, ENTITY *entity,
       entity->is_param ? "%" : "&", entityName, action, entity->textLen,
       sourceLine);
 }
+#endif
+/* END MOZILLA CHANGE */
 
 static void
 entityTrackingOnOpen(XML_Parser originParser, ENTITY *entity, int sourceLine) {
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
   const XML_Parser rootParser = getRootParserOf(originParser, NULL);
   assert(! rootParser->m_parentParser);
 
@@ -8832,15 +8910,21 @@ entityTrackingOnOpen(XML_Parser originParser, ENTITY *entity, int sourceLine) {
   }
 
   entityTrackingReportStats(rootParser, entity, "OPEN ", sourceLine);
+#endif
+/* END MOZILLA CHANGE */
 }
 
 static void
 entityTrackingOnClose(XML_Parser originParser, ENTITY *entity, int sourceLine) {
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
   const XML_Parser rootParser = getRootParserOf(originParser, NULL);
   assert(! rootParser->m_parentParser);
 
   entityTrackingReportStats(rootParser, entity, "CLOSE", sourceLine);
   rootParser->m_entity_stats.currentDepth--;
+#endif
+/* END MOZILLA CHANGE */
 }
 
 #endif /* XML_GE == 1 */
@@ -8862,6 +8946,8 @@ getRootParserOf(XML_Parser parser, unsigned int *outLevelDiff) {
 
 #if XML_GE == 1
 
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
 const char *
 unsignedCharToPrintable(unsigned char c) {
   switch (c) {
@@ -9385,9 +9471,13 @@ unsignedCharToPrintable(unsigned char c) {
   assert(0); /* never gets here */
   // LCOV_EXCL_STOP
 }
+#endif
+/* END MOZILLA CHANGE */
 
 #endif /* XML_GE == 1 */
 
+/* BEGIN MOZILLA CHANGE (don't report debug information) */
+#if 0
 static unsigned long
 getDebugLevel(const char *variableName, unsigned long defaultDebugLevel) {
   const char *const valueOrNull = getenv(variableName);
@@ -9406,3 +9496,5 @@ getDebugLevel(const char *variableName, unsigned long defaultDebugLevel) {
 
   return debugLevel;
 }
+#endif
+/* END MOZILLA CHANGE */