A release candidate for GCC 6.4 is available from ftp://gcc.gnu.org/pub/gcc/snapshots/6.4.0-RC-20170628/
and shortly its mirrors. It has been generated from SVN revision 249715. I have so far bootstrapped and tested the release candidate on x86_64-unknown-linux-gnu. Please test it and report any issues to bugzilla. If all goes well I'd like to release 6.4 on Tuesday, July 4th.
