45 lines
1.8 KiB
Diff
45 lines
1.8 KiB
Diff
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From 40d3f2d7ef5835317fe9df9ecc01f4c363def4fd Mon Sep 17 00:00:00 2001
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From: =?UTF-8?q?Sebastian=20Dr=C3=B6ge?= <sebastian@centricular.com>
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Date: Thu, 4 Feb 2021 10:23:01 +0200
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Subject: [PATCH] Increment `self.index` before calling
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`Iterator::self.a.__iterator_get_unchecked` in `Zip` `TrustedRandomAccess`
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specialization
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Otherwise if `Iterator::self.a.__iterator_get_unchecked` panics the
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index would not have been incremented yet and another call to
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`Iterator::next` would read from the same index again, which is not
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allowed according to the API contract of `TrustedRandomAccess` for
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`!Clone`.
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Fixes https://github.com/rust-lang/rust/issues/81740
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(cherry picked from commit 86a4b27475aab52b998c15f5758540697cc9cff0)
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---
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library/core/src/iter/adapters/zip.rs | 7 ++++---
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1 file changed, 4 insertions(+), 3 deletions(-)
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diff --git a/library/core/src/iter/adapters/zip.rs b/library/core/src/iter/adapters/zip.rs
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index 98b8dca96140..9f9835345200 100644
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--- a/library/core/src/iter/adapters/zip.rs
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+++ b/library/core/src/iter/adapters/zip.rs
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@@ -198,12 +198,13 @@ fn next(&mut self) -> Option<(A::Item, B::Item)> {
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Some((self.a.__iterator_get_unchecked(i), self.b.__iterator_get_unchecked(i)))
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}
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} else if A::may_have_side_effect() && self.index < self.a.size() {
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+ let i = self.index;
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+ self.index += 1;
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// match the base implementation's potential side effects
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- // SAFETY: we just checked that `self.index` < `self.a.len()`
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+ // SAFETY: we just checked that `i` < `self.a.len()`
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unsafe {
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- self.a.__iterator_get_unchecked(self.index);
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+ self.a.__iterator_get_unchecked(i);
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}
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- self.index += 1;
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None
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} else {
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None
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--
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2.31.1
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