effects: don't taint :noub for :new allocations
#52222
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After #52169, the UB previously associated with allocations with uninitialized fields has been addressed, so there's no longer a need to taint `:noub` for `:new` allocations during abstract interpretation. I believe, even without #52169, uninitialized field does not inherently leads to UB, but just causes inconsistency of the program, since what actually causes UB is `getfield` that accesses into whatever object, but not the allocation itself.
Keno
approved these changes
Nov 18, 2023
This is correct, but LLVM is only exploiting the UB if it sees both the allocation and the access, so tainting the allocation was an easy way to catch all the relevant cases, but that is moot now of course. |
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After #52169, the UB previously associated with allocations with uninitialized fields has been addressed, so there's no longer a need to taint
:noubfor:newallocations during abstract interpretation.I believe, even without #52169, uninitialized field does not inherently leads to UB, but just causes inconsistency of the program, since what actually causes UB is
getfieldthat accesses into whatever object, but not the allocation itself.