dataflow: avoid propagating offset permissions upward from field access #1031
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c2rust-analyze/src/context.rs
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| /// Returns the [`LTy`] of an [`Rvalue`] and a boolean indicating whether or | ||
| /// not the `Rvalue` contains a field projection. |
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Can you clarify the precise meaning of "the Rvalue contains a field projection"? Which of these count as containing a field projection?
let r1 = x.field;
let r2 = &x.field;
let r3 = &(*p).field;
let r4 = x.field + y;
// ^ Rvalue::Add(Operand::Copy(x.field), ...)There was a problem hiding this comment.
Added clarification in fbdcfe8
spernsteiner
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Oct 11, 2023
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…rojection that should inform offset propagation
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Pointers to structs with array fields being iterated over via
offsetwere erroneously being givenOFFSETpermissions. Those permissions should be limited to the fields themselves. This PR introduces a new dataflow constraint that will propagate permissions except for a specified set. When a field projection is detected, offset permissions are no longer propagated to the base pointer.