Hi, thanks for the bug report.
I fixed this upstream some time ago, patch attached. However, I'd like to do some further cleanup first, and then do a new upstream release. Unfortunately, I cannot tell when I will have some time to do and coordinate this. So if anyone wants to NMU this, here is the patch (#846422 should be self-explanatory and straightforward to fix). Feel free to go ahead. Cheers and thanks, Stefan.
--- a/src/frontend/newparser/FAUhdlScanner.hpp +++ b/src/frontend/newparser/FAUhdlScanner.hpp @@ -23,8 +23,8 @@ public: // arg_yyin and arg_yyout default to the cin and cout, but we // only make that assignment when initializing in yylex(). FAUhdlScanner( - FLEX_STD istream* arg_yyin = 0, - FLEX_STD ostream* arg_yyout = 0 + std::istream* arg_yyin = 0, + std::ostream* arg_yyout = 0 ) : yyFlexLexer(arg_yyin, arg_yyout), bracesCtr(0), isAssociation(false),