Apply updated patches from #8476.

Fixes #8476.

[SVN r84052]

include/boost/regex/v4/basic_regex_parser.hpp

@@ -369,7 +369,6 @@ bool basic_regex_parser<charT, traits>::parse_extended()
          while((m_position != m_end) && !is_separator(*m_position++)){}
          return true;
       }
-      // Otherwise fall through:
       BOOST_FALLTHROUGH;
    default:
       result = parse_literal();
@@ -624,7 +623,6 @@ bool basic_regex_parser<charT, traits>::parse_basic_escape()
          {
          case 'w':
             negate = false;
-            // fall through:
             BOOST_FALLTHROUGH;
          case 'W':
             {
@@ -642,7 +640,6 @@ bool basic_regex_parser<charT, traits>::parse_basic_escape()
             }
          case 's':
             negate = false;
-            // fall through:
             BOOST_FALLTHROUGH;
          case 'S':
             return add_emacs_code(negate);
@@ -675,7 +672,6 @@ bool basic_regex_parser<charT, traits>::parse_extended_escape()
    {
    case regex_constants::escape_type_not_class:
       negate = true;
-      // fall through:
       BOOST_FALLTHROUGH;
    case regex_constants::escape_type_class:
       {
@@ -746,7 +742,6 @@ escape_type_class_jump:
       break;
    case regex_constants::escape_type_not_property:
       negate = true;
-      // fall through:
       BOOST_FALLTHROUGH;
    case regex_constants::escape_type_property:
       {
@@ -906,7 +901,7 @@ escape_type_class_jump:
    case regex_constants::escape_type_control_v:
       if(0 == (this->flags() & (regbase::main_option_type | regbase::no_perl_ex)))
          goto escape_type_class_jump;
-      // fallthrough:
+      BOOST_FALLTHROUGH;
    default:
       this->append_literal(unescape_character());
       break;
@@ -1964,7 +1959,6 @@ bool basic_regex_parser<charT, traits>::parse_perl_extension()
    {
    case regex_constants::syntax_or:
       m_mark_reset = m_mark_count;
-      // fall through:
       BOOST_FALLTHROUGH;
    case regex_constants::syntax_colon:
       //