Modify the ExprUseVisitor to walk each part of an AutoRef #24191
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Reassigning to @pnkfelix - I really don't know ExprUseVisitor as well as I should, sorry. |
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| fn main() { | ||
| let x: &i32; | ||
| let y = x as *const Foo; //~ ERROR use of possibly uninitialized variable: `*x` |
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@nikomatsakis r=me when above issues are addressed. |
particular to treat an AutoUnsize as as kind of "instantaneous" borrow of the value being unsized. This prevents us from feeding uninitialized data. This caused a problem for the eager reborrow of comparison traits, because that wound up introducing a "double AutoRef", which was not being thoroughly checked before but turned out not to type check. Fortunately, we can just remove that "eager reborrow" as it is no longer needed now that `PartialEq` doesn't force both LHS and RHS to have the same type (and even if we did have this problem, the better way would be to lean on introducing a common supertype).
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Modify the ExprUseVisitor to walk each part of an AutoRef, and in particular to treat an AutoUnsize as as kind of \"instantaneous\" borrow of the value being unsized. This prevents us from feeding uninitialized data. This caused a problem for the eager reborrow of comparison traits, because that wound up introducing a \"double AutoRef\", which was not being thoroughly checked before but turned out not to type check. Fortunately, we can just remove that \"eager reborrow\" as it is no longer needed now that `PartialEq` doesn't force both LHS and RHS to have the same type (and even if we did have this problem, the better way would be to lean on introducing a common supertype). Fixes rust-lang#20791. r? @nrc
Manishearth
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Apr 9, 2015
Modify the ExprUseVisitor to walk each part of an AutoRef, and in particular to treat an AutoUnsize as as kind of \"instantaneous\" borrow of the value being unsized. This prevents us from feeding uninitialized data. This caused a problem for the eager reborrow of comparison traits, because that wound up introducing a \"double AutoRef\", which was not being thoroughly checked before but turned out not to type check. Fortunately, we can just remove that \"eager reborrow\" as it is no longer needed now that `PartialEq` doesn't force both LHS and RHS to have the same type (and even if we did have this problem, the better way would be to lean on introducing a common supertype). Fixes rust-lang#20791. r? @nrc
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Modify the ExprUseVisitor to walk each part of an AutoRef, and in
particular to treat an AutoUnsize as as kind of "instantaneous" borrow
of the value being unsized. This prevents us from feeding uninitialized
data.
This caused a problem for the eager reborrow of comparison traits,
because that wound up introducing a "double AutoRef", which was not
being thoroughly checked before but turned out not to type check.
Fortunately, we can just remove that "eager reborrow" as it is no longer
needed now that
PartialEqdoesn't force both LHS and RHS to have thesame type (and even if we did have this problem, the better way would be
to lean on introducing a common supertype).
Fixes #20791.
r? @nrc