auto merge of #6174 : sanxiyn/rust/static-string, r=brson

diff --cc src/librustc/driver/session.rs
Simple merge

diff --cc src/librustc/middle/check_const.rs
Simple merge

diff --cc src/librustc/middle/check_match.rs
Simple merge

diff --cc src/librustc/middle/kind.rs
Simple merge

diff --cc src/librustc/middle/lint.rs
Simple merge

diff --cc src/librustc/middle/ty.rs
Simple merge