LHS of assign op is invariant #52564
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Therefore we cannot coerce it to a supertype the same way that we can the LHS of `+`. Addresses issue 52126.
… linker failure. Rather than try to work out what was happening, I just removed the flag because I see no reason for it to be on this test.
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r? @cramertj (rust_highfive has picked a reviewer for you, use r? to override) |
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r? @eddyb |
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/facepalm of course (I probably completely missed that @bors r+ |
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📌 Commit f153be6 has been approved by |
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…iant, r=eddyb LHS of assign op is invariant This addresses a bug injected by #45435. That PR changed the way we type-check `LHS <op> RHS` to coerce the LHS to the expected supertype in much the same way that we coerce the RHS. The problem is that when we have a case of `LHS <op>= RHS`, we do not want to coerce to a supertype; we need the type to remain invariant. Otherwise we risk leaking a value with short-lifetimes into a expression context that needs to satisfy a long lifetime. Fix #52126
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☀️ Test successful - status-appveyor, status-travis |
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This addresses a bug injected by #45435. That PR changed the way we type-check
LHS <op> RHSto coerce the LHS to the expected supertype in much the same way that we coerce the RHS.The problem is that when we have a case of
LHS <op>= RHS, we do not want to coerce to a supertype; we need the type to remain invariant. Otherwise we risk leaking a value with short-lifetimes into a expression context that needs to satisfy a long lifetime.Fix #52126