lowering: Fix accidental clearing of never-undef flag in closure convert#51991
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lowering: Fix accidental clearing of never-undef flag in closure convert#51991
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…ersion pass This code dates back all the way to the original closure conversion code. At the time, the 0x4 bit of the vinfo was used for tracking whether a variable is assigned in an inner function, which apparently needed to be cleared during closure conversion. However, shortly afterwards, the bit was removed [3] and subsequently re-used for never-undef [4]. However, the magic number in the closure conversion pass was never updated, causing the new never-undef flag to be accidentally cleared unconditionally. [1] a1ee867 [2] https://github.com/JuliaLang/julia/blob/a1ee8676f00fc14bd67aaf7eb20ce46ff99f322e/src/ast.scm#L217-L218 [3] 7e7d743 [4] 3d8f8d1 Co-authored-by: Jeff Bezanson <jeff@juliahub.com>
JeffBezanson
approved these changes
Nov 2, 2023
vtjnash
approved these changes
Nov 2, 2023
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This code dates back all the way to the original closure conversion code [1]. At the time, the 0x4 bit of the vinfo was used for tracking whether a variable is assigned in an inner function [2], which apparently needed to be cleared during closure conversion. However, shortly afterwards, the bit was removed [3] and subsequently re-used for never-undef [4]. However, the magic number in the closure conversion pass was never updated, causing the new never-undef flag to be accidentally cleared unconditionally.
[1] a1ee867
[2]
julia/src/ast.scm
Lines 217 to 218 in a1ee867
[3] 7e7d743
[4] 3d8f8d1