------- Comment #3 from pcarlini at suse dot de 2008-03-30 09:24 ------- This is tightly coupled to libstdc++/35353: in the current design, when sync_with_stdio is false (by default), the stream is non-converting and synced with C stdio, simply forwards to stdio functions. Unfortunately, the fix is not forthcoming, there are very serious performance implications, and binary compatibility issues (which probably can be solve only by breaking the ABI).
-- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35763
