Problem with GCC 4.9.0, Wextra, c++1y, and post-preprocessed linux header files

[Jonathan Wakely]

On 24 April 2014 17:44, Matt Godbolt wrote:
> This only happens with std=c++1y, Wextra and -O (which macro-izes
> htonl instead of making it an external function).  It does not happen
> with std=c++11.

I don't have an answer, but  this reminds me of
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57573