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This is rejected by rustc as "trivi= al > bounds", which can only be specified using the > `#![feature(trivial_bounds)]`. > > Currently we use an extra lifetime in `__Unpin` to work around this; use > HRTB to introduce a dummy lifetime can achieve the same, which the > `Zeroable` implementation already uses. > > Unify the `Unpin` impl to also use the same HRTB trick that `Zeroable` > uses. This produces slightly better error message and slightly shorter > expansion. > > Signed-off-by: Gary Guo Applied to pin-init-next. Best, Gary > --- > rust/pin-init/internal/src/pin_data.rs | 35 +++++++++----------------- > rust/pin-init/src/__internal.rs | 16 ------------ > 2 files changed, 12 insertions(+), 39 deletions(-)