Update static exclusivity diagnostics to not suggest copying to a local
when a call to swapAt() should be used instead. We already emit a FixIt in
this case, so don't suggest an an helpful fix in the diagnostic.
rdar://problem/32296784
Remove the descriptive decl kind (since with subpaths it is not correct and
cannot represent a tuple element) and change "simultaneous" to "overlapping"
in order to lower the register slightly and avoid connoting threading.
For example, for the following:
takesTwoInouts(&x.f, &x.f)
the diagnostic will change from
"simultaneous accesses to var 'x.f', but modification requires exclusive access;
consider copying to a local variable"
to
"overlapping accesses to 'x.f', but modification requires exclusive access;
consider copying to a local variable"
Turn on static checks for the already-accepted portions of SE-0176: Enforce
Exclusive Access to Memory.
This includes static checking for overlapping inout parameter accesses
(and inout-to-pointer accesses).
Static violations are warnings in Swift 3 compatibility mode and errors
in Swift 4 mode.
Dynamic enforcement is not enabled by default.
This does not add static checking for the Non-Escaping Recursion
Restriction rule nor the Non-Escaping Parameter Call Restriction rule. These
are revisions to SE-0176 still under review.
A stored property of a class may be overridden by a computed one, and a property requirement may be witnessed by a computed property, but rejecting inout aliasing in these cases isn't very helpful. Only reject cases that are definitely computed and will always behave incorrectly. Fixes rdar://problem/19633414.
Swift SVN r24986
