Fix unaligned loads in librustc_metadata #38352
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r? @pnkfelix (rust_highfive has picked a reviewer for you, use r? to override) |
bluss
commented
Dec 13, 2016
| fn bytes_to_words(b: &[u8]) -> &[u32] { | ||
| unsafe { slice::from_raw_parts(b.as_ptr() as *const u32, b.len() / 4) } | ||
| fn bytes_to_words(b: &[u8]) -> UnalignedIter<u32> { | ||
| UnalignedIter::from_slice(b) |
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hm.. no, sorry! It is from before that.
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This was reported as a crash on sparc64. |
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bluss
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Dec 13, 2016
| @@ -95,8 +98,8 @@ impl<'tcx> LazySeq<Index> { | |||
| } | |||
| } | |||
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| fn bytes_to_words(b: &[u8]) -> &[u32] { | |||
| unsafe { slice::from_raw_parts(b.as_ptr() as *const u32, b.len() / 4) } | |||
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Maybe we should lint against this? Creating a slice or reference from a less aligned pointer?
Creating a `&[u32]` from a `&[u8]` was not valid; the data is not necessarily well aligned.
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Hey presto, the diff is much shorter with a bit of help from @eddyb. |
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@bors r+ |
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📌 Commit 7bc1054 has been approved by |
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Dec 16, 2016
Fix unaligned loads in librustc_metadata Creating a `&[u32]` from an `&[u8]` is not necessarily valid, and crashes on certain platforms if the data is not well aligned.
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Creating a
&[u32]from an&[u8]is not necessarily valid, and crasheson certain platforms if the data is not well aligned.