gdb/

gdb/
	PR exp/12117
	* gdbtypes.c (check_typedef): Clean up function comment.
	Keep track of instance flags as we strip typedefs and create a new
	type to preserve them if necessary.
	* gdbtypes.h (type) <instance_flags>: Extend the comment.

gdb/testsuite/
	PR exp/12117
	* gdb.cp/ptype-cv-cp.cc: New file.
	* gdb.cp/ptype-cv-cp.exp: New file.