[5.9] Fix MoveOnlyAddressChecker to handle value deinits #66778
Merged
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Fixes rdar://110232973 ([move-only] Checker should distinguish in between field of single field struct vs parent field itself (was: mutation of field in noncopyable struct should not trigger deinit))
(cherry picked from commit a8c45c5)
--- CCC ---
Explanation: Track liveness of self so we don't accidentally think that such types can be memberwise reinitialized.
Scope of Issue: Miscompilation occurs for a NonCopyable struct with a deinit. The deinitializer incorrectly runs when the programmer reassigns the struct fields.
Risk: This change only affects the MoveOnlyAddressChecker, which was already miscompiling cases that weren't explicitly tested.
PR to main: Fix MoveOnlyAddressChecker to handle value deinits. #66691
Reviewed By: Michael Gottesman
Resolves: rdar://110232973 ([move-only] Checker should distinguish in between field of single field struct vs parent field itself (was: mutation of field in noncopyable struct should not trigger deinit))