Index: boost/format/parsing.hpp
===================================================================
--- boost/format/parsing.hpp	(revision 84007)
+++ boost/format/parsing.hpp	(working copy)
@@ -267,6 +267,7 @@
         switch ( wrap_narrow(fac, *start, 0) ) {
         case 'X':
             fpar->fmtstate_.flags_ |= std::ios_base::uppercase;
+            BOOST_FALLTHROUGH;
         case 'p': // pointer => set hex.
         case 'x':
             fpar->fmtstate_.flags_ &= ~std::ios_base::basefield;
@@ -280,6 +281,7 @@
 
         case 'E':
             fpar->fmtstate_.flags_ |=  std::ios_base::uppercase;
+            BOOST_FALLTHROUGH;
         case 'e':
             fpar->fmtstate_.flags_ &= ~std::ios_base::floatfield;
             fpar->fmtstate_.flags_ |=  std::ios_base::scientific;
@@ -291,6 +293,7 @@
         case 'f':
             fpar->fmtstate_.flags_ &= ~std::ios_base::floatfield;
             fpar->fmtstate_.flags_ |=  std::ios_base::fixed;
+            BOOST_FALLTHROUGH;
         case 'u':
         case 'd':
         case 'i':