Right now the stdlib/overlays can compile against -Onone tests with or without
-enable-ownership-stripping-after-serialization. This will help me to prevent
other work going on from breaking these properties.
In Swift 4.1 we fixed a false negative and started looking through
reabstraction thunks to statically find exclusivity violations. To lessen
source impact, we treated these violations as warnings. This commit upgrades
those warnings to errors.
rdar://problem/34669400
Update static enforcement to look through noescape blocks to find an underlying
noescape closure when a closure is converted to a block and passed as an
argument to a function. This fixes a false negative when the closure performs
an access that conflicts with an already in-progress access.
These new diagnostics are warnings for source compatibility but will
be upgraded to errors in the future.
rdar://problem/32912660
