It appears that the files under /include/g++-3/ , as well as the stdc++ library files are not included in the mingw-runtime distribution.
 
As far as I can tell, this makes it difficult or impossible to compile programs using the std c++ library using the runtime distribution.
 
It also contributes to cygwin's g++ -mno-cygwin option being somewhat worthless, since cygwin seems to rely on the mingw-runtime distribution to provide headers & libs for the -mno-cygwin option.
 
Is this by design, or just an oversight? Could this be changed in a future release?
 
Regards,
David Carter
david@carter.net