Avoid O(n^2) performance by checking reduced set of obligations #18386
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nikomatsakis
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In truth, I don't think we need to be so eager about selecting new obligations. We should probably wait until we want information we don't have, and then try new-obligations and finally all obligations. |
nikomatsakis
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lgtm, feel free to r=me after squashing. |
… only when we are about to report an error (rust-lang#18208). I found it is still important to consider the full set in order to make tests like `let x: Vec<_> = obligations.iter().collect()` work.
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Avoid O(n^2) performance by reconsidering the full set of obligations only when we are about to report an error (#18208). I found it is still important to consider the full set in order to make tests like `let x: Vec<_> = obligations.iter().collect()` work. I think we lack the infrastructure to write a regression test for this, but when I did manual testing I found a massive reduction in type-checking time for extreme examples like those found in #18208 vs stage0. f? @dotdash
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LGTM, type checking can now handle enough |
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Avoid O(n^2) performance by reconsidering the full set of obligations only when we are about to report an error (#18208). I found it is still important to consider the full set in order to make tests like
let x: Vec<_> = obligations.iter().collect()work.I think we lack the infrastructure to write a regression test for this, but when I did manual testing I found a massive reduction in type-checking time for extreme examples like those found in #18208 vs stage0.
f? @dotdash