b6657a8ad4
HIR typeck tries to figure out which casts are trivial by doing them as coercions and seeing whether this works. Since HIR typeck is oblivious of lifetimes, this doesn't work for pointer casts that only change the lifetime of the pointee, which are, as borrowck will tell you, not trivial. This change makes it so that raw pointer casts are never considered trivial. This also incidentally fixes the "trivial cast" lint false positive on the same code. Unfortunately, "trivial cast" lints are now never emitted on raw pointer casts, even if they truly are trivial. This could be fixed by also doing the lint in borrowck for raw pointers specifically.
35 lines
866 B
Diff
35 lines
866 B
Diff
- // MIR for `redundant` before InstSimplify
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+ // MIR for `redundant` after InstSimplify
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fn redundant(_1: *const &u8) -> *const &u8 {
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debug x => _1;
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let mut _0: *const &u8;
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let mut _2: *const &u8;
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let mut _3: *const &u8;
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let mut _4: *const &u8;
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scope 1 (inlined generic_cast::<&u8, &u8>) {
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debug x => _4;
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let mut _5: *const &u8;
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}
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bb0: {
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StorageLive(_2);
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StorageLive(_3);
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StorageLive(_4);
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_4 = _1;
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StorageLive(_5);
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_5 = _4;
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- _3 = move _5 as *const &u8 (PtrToPtr);
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+ _3 = move _5;
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StorageDead(_5);
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StorageDead(_4);
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- _2 = move _3 as *const &u8 (PtrToPtr);
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+ _2 = move _3;
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_0 = _2;
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StorageDead(_3);
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StorageDead(_2);
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return;
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}
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}
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