diff --git a/xpcom/libxpt/xptinfo/src/nsInterfaceInfoManager.cpp b/xpcom/libxpt/xptinfo/src/nsInterfaceInfoManager.cpp
index f02c72cff5d4..160f7909cafe 100644
--- a/xpcom/libxpt/xptinfo/src/nsInterfaceInfoManager.cpp
+++ b/xpcom/libxpt/xptinfo/src/nsInterfaceInfoManager.cpp
@@ -164,10 +164,10 @@ indexify_file(const char *filename,
     int limit = header->num_interfaces;
 
     interface_record *value;
-//#ifdef DEBUG_mccabe
+#ifdef DEBUG_mccabe
     static int which = 0;
     which++;
-//#endif
+#endif
     for (int i = 0; i < limit; i++) {
         XPTInterfaceDirectoryEntry *current = header->interface_directory + i;
 
@@ -195,7 +195,7 @@ indexify_file(const char *filename,
 #endif
             NS_ASSERTION(hashEntry != NULL, "PL_HashTableAdd failed?");
         }
-#ifdef DEBUG_MCCABE
+#ifdef DEBUG_mccabe
         else {
             fprintf(stderr, "... found, %d\n", value->which);
         }
@@ -208,7 +208,9 @@ indexify_file(const char *filename,
                          "some interface def'd in multiple typelibs.");
             value->which_header = header;
             value->resolved = PR_TRUE;
+#ifdef DEBUG_mccabe
             value->which = which;
+#endif
             value->entry = current;
 
             // XXX is this a leak?
diff --git a/xpcom/libxpt/xptinfo/src/nsInterfaceInfoManager.h b/xpcom/libxpt/xptinfo/src/nsInterfaceInfoManager.h
index f7a4fd04b341..b0af7eadceb7 100644
--- a/xpcom/libxpt/xptinfo/src/nsInterfaceInfoManager.h
+++ b/xpcom/libxpt/xptinfo/src/nsInterfaceInfoManager.h
@@ -71,7 +71,6 @@ private:
     // (record handling is looked up by name; iids are translated there)
     nsHashtable *mIIDTable;
 
-    nsInterfaceInfo *mParent;
     nsIAllocator* mAllocator;
 };
 
@@ -80,9 +79,12 @@ class interface_record {
 public:
     XPTHeader *which_header;
     PRBool resolved;
-    int which;
     XPTInterfaceDirectoryEntry *entry;
     nsInterfaceInfo *info;
+#ifdef DEBUG
+    // which (counting from 1) typelib was it loaded from?
+    int which;
+#endif
 };    
 
 
diff --git a/xpcom/reflect/xptinfo/src/nsInterfaceInfoManager.cpp b/xpcom/reflect/xptinfo/src/nsInterfaceInfoManager.cpp
index f02c72cff5d4..160f7909cafe 100644
--- a/xpcom/reflect/xptinfo/src/nsInterfaceInfoManager.cpp
+++ b/xpcom/reflect/xptinfo/src/nsInterfaceInfoManager.cpp
@@ -164,10 +164,10 @@ indexify_file(const char *filename,
     int limit = header->num_interfaces;
 
     interface_record *value;
-//#ifdef DEBUG_mccabe
+#ifdef DEBUG_mccabe
     static int which = 0;
     which++;
-//#endif
+#endif
     for (int i = 0; i < limit; i++) {
         XPTInterfaceDirectoryEntry *current = header->interface_directory + i;
 
@@ -195,7 +195,7 @@ indexify_file(const char *filename,
 #endif
             NS_ASSERTION(hashEntry != NULL, "PL_HashTableAdd failed?");
         }
-#ifdef DEBUG_MCCABE
+#ifdef DEBUG_mccabe
         else {
             fprintf(stderr, "... found, %d\n", value->which);
         }
@@ -208,7 +208,9 @@ indexify_file(const char *filename,
                          "some interface def'd in multiple typelibs.");
             value->which_header = header;
             value->resolved = PR_TRUE;
+#ifdef DEBUG_mccabe
             value->which = which;
+#endif
             value->entry = current;
 
             // XXX is this a leak?
diff --git a/xpcom/reflect/xptinfo/src/nsInterfaceInfoManager.h b/xpcom/reflect/xptinfo/src/nsInterfaceInfoManager.h
index f7a4fd04b341..b0af7eadceb7 100644
--- a/xpcom/reflect/xptinfo/src/nsInterfaceInfoManager.h
+++ b/xpcom/reflect/xptinfo/src/nsInterfaceInfoManager.h
@@ -71,7 +71,6 @@ private:
     // (record handling is looked up by name; iids are translated there)
     nsHashtable *mIIDTable;
 
-    nsInterfaceInfo *mParent;
     nsIAllocator* mAllocator;
 };
 
@@ -80,9 +79,12 @@ class interface_record {
 public:
     XPTHeader *which_header;
     PRBool resolved;
-    int which;
     XPTInterfaceDirectoryEntry *entry;
     nsInterfaceInfo *info;
+#ifdef DEBUG
+    // which (counting from 1) typelib was it loaded from?
+    int which;
+#endif
 };