diff --git a/expat/lib/xmlparse.c b/expat/lib/xmlparse.c
index b25aa2ed..59da19c8 100644
--- a/expat/lib/xmlparse.c
+++ b/expat/lib/xmlparse.c
@@ -722,6 +722,7 @@ XML_ParserCreateNS(const XML_Char *encodingName, XML_Char nsSep) {
   return XML_ParserCreate_MM(encodingName, NULL, tmp);
 }
 
+// "xml=http://www.w3.org/XML/1998/namespace"
 static const XML_Char implicitContext[]
     = {ASCII_x,     ASCII_m,     ASCII_l,      ASCII_EQUALS, ASCII_h,
        ASCII_t,     ASCII_t,     ASCII_p,      ASCII_COLON,  ASCII_SLASH,
@@ -3710,6 +3711,7 @@ storeAtts(XML_Parser parser, const ENCODING *enc, const char *attStr,
 static enum XML_Error
 addBinding(XML_Parser parser, PREFIX *prefix, const ATTRIBUTE_ID *attId,
            const XML_Char *uri, BINDING **bindingsPtr) {
+  // "http://www.w3.org/XML/1998/namespace"
   static const XML_Char xmlNamespace[]
       = {ASCII_h,      ASCII_t,     ASCII_t,     ASCII_p,      ASCII_COLON,
          ASCII_SLASH,  ASCII_SLASH, ASCII_w,     ASCII_w,      ASCII_w,
@@ -3720,6 +3722,7 @@ addBinding(XML_Parser parser, PREFIX *prefix, const ATTRIBUTE_ID *attId,
          ASCII_e,      ASCII_s,     ASCII_p,     ASCII_a,      ASCII_c,
          ASCII_e,      '\0'};
   static const int xmlLen = (int)sizeof(xmlNamespace) / sizeof(XML_Char) - 1;
+  // "http://www.w3.org/2000/xmlns/"
   static const XML_Char xmlnsNamespace[]
       = {ASCII_h,     ASCII_t,      ASCII_t, ASCII_p, ASCII_COLON,  ASCII_SLASH,
          ASCII_SLASH, ASCII_w,      ASCII_w, ASCII_w, ASCII_PERIOD, ASCII_w,