Fix a bug in abs_diff
#736
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These implementations of `abs_diff` were added in c2ff1b3 ("Completely overhaul fuzz testing"), but the signed implementation is wrong when |x| + |y| exceeds the integer's limits (e.g. `(-128).abs_diff(1)` should be 128 but currently these return 127. Resolve this by just using `std`'s implementation since that is stable now. This isn't used anywhere critical, we probably just weren't hitting the edge case.
tgross35
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Dec 22, 2024
These were taken from `compiler-builtins` but the implementation has a bug near the integer limits. Fixed in `compiler-builtins` by using `core`'s implementation at [1], this is the corresponding fix for `libm`. [1]: rust-lang/compiler-builtins#736
It should be 129, right? |
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Ah yeah that's a typo, how did you stumble across this and find that :). Updated the description. |
tgross35
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Dec 27, 2024
Nothing significant here, just syncing the following small changes: - rust-lang/compiler-builtins#727 - rust-lang/compiler-builtins#730 - rust-lang/compiler-builtins#736 - rust-lang/compiler-builtins#737
tgross35
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Nothing significant here, just syncing the following small changes: - rust-lang/compiler-builtins#727 - rust-lang/compiler-builtins#730 - rust-lang/compiler-builtins#736 - rust-lang/compiler-builtins#737
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I saw the PR listed in TWiR and the title made me curious, then read the description and got confused. ;)
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Zalathar
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Dec 28, 2024
Update `compiler-builtins` to 0.1.140 Nothing significant here, just syncing the following small changes: - rust-lang/compiler-builtins#727 - rust-lang/compiler-builtins#730 - rust-lang/compiler-builtins#736 - rust-lang/compiler-builtins#737
rust-timer
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Dec 28, 2024
Rollup merge of rust-lang#134832 - tgross35:update-builtins, r=tgross35 Update `compiler-builtins` to 0.1.140 Nothing significant here, just syncing the following small changes: - rust-lang/compiler-builtins#727 - rust-lang/compiler-builtins#730 - rust-lang/compiler-builtins#736 - rust-lang/compiler-builtins#737
poliorcetics
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Dec 28, 2024
Nothing significant here, just syncing the following small changes: - rust-lang/compiler-builtins#727 - rust-lang/compiler-builtins#730 - rust-lang/compiler-builtins#736 - rust-lang/compiler-builtins#737
poliorcetics
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Dec 28, 2024
Update `compiler-builtins` to 0.1.140 Nothing significant here, just syncing the following small changes: - rust-lang/compiler-builtins#727 - rust-lang/compiler-builtins#730 - rust-lang/compiler-builtins#736 - rust-lang/compiler-builtins#737
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These implementations of
abs_diffwere added in c2ff1b3 ("Completely overhaul fuzz testing"), but the signed implementation is wrong when |x| + |y| exceeds the integer's limits (e.g.(-128).abs_diff(1)should be 129 but currently these return 127.Resolve this by just using
std's implementation since that is stable now. This isn't used anywhere critical, we probably just weren't hitting the edge case.