6420803549
This patch changes <experimental/foo> to use #warning instead of is harmful to common feature detection idioms. We should also consider only emitting the warning when __DEPRECATED is defined, like we do in the <ext/foo> headers. Users may want to specify "-Werror=-W#warnings" while still ignoring the libc++ warnings. git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@350485 91177308-0d34-0410-b5e6-96231b3b80d8