merge from gcc

libiberty/cp-demangle.c

@@ -1280,6 +1280,7 @@ d_nested_name (struct d_info *di)
 /* <prefix> ::= <prefix> <unqualified-name>
             ::= <template-prefix> <template-args>
             ::= <template-param>
+            ::= <decltype>
             ::=
             ::= <substitution>
 
@@ -1308,10 +1309,19 @@ d_prefix (struct d_info *di)
 	 <template-param> here.  */
 
       comb_type = DEMANGLE_COMPONENT_QUAL_NAME;
-      if (IS_DIGIT (peek)
+      if (peek == 'D')
+	{
+	  char peek2 = d_peek_next_char (di);
+	  if (peek2 == 'T' || peek2 == 't')
+	    /* Decltype.  */
+	    dc = cplus_demangle_type (di);
+	  else
+	    /* Destructor name.  */
+	    dc = d_unqualified_name (di);
+	}
+      else if (IS_DIGIT (peek)
 	  || IS_LOWER (peek)
 	  || peek == 'C'
-	  || peek == 'D'
 	  || peek == 'U'
 	  || peek == 'L')
 	dc = d_unqualified_name (di);