4.4 use static_assert or #warning for unimplemented c++0x std libs

[Joe Buck]

On Mon, Jan 05, 2009 at 11:39:55AM -0800, Chris wrote:
> Is it possible to have some sort of protocol in gcc, so that any
> unimplemented library function uses #warning or static_assert(0,"regex
> not implemented") to not to confuse any future users?   I don't think
> gcc should provide headers that compile but don't do anything.

Yes, it will make it awful hard for autoconf users trying to determine
if a feature is supported, if use of that feature produces functions that
compile, link, and do nothing with a report of success.