No, I mean that if you do advanced string manipulation in the exception itself, you may screw up, adn cause a bad_alloc beign thrown and masking your own exception.
Create an error sentence with some values inside is not really an advanced string manipulation. You can have 2 kinds of errors: bug inside a custom operator<< or a memory problem. There is no particular reason to not have sufficient memory to create an error sentence when throwing something like a logic_error.
Just make your own, informative exception type deriving from logic_error. The problem is not really the kind of exception, but an easy way to create message with boost exception tag system.
The idea is to create a new base class for tags allowing to use an ostringstream with tags, which is not possible. typedef ::boost::error_info<struct tag_message,std::ostringstream> message; This little class only remap operator+ call to operator<< on an internal ostringstream. typedef ::boost::error_info<struct tag_message,::boost::error_info_sstream> message; I use it in my code, but I ask here if we can hope to see such things in boost exception. I would prefer to use a standard boost object rather than a custom class.