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| author | whitequark <whitequark@whitequark.org> | 2015-09-20 22:19:30 +0300 |
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| committer | whitequark <whitequark@whitequark.org> | 2015-09-20 22:23:35 +0300 |
| commit | 77f5da77a91af88130fcff3e726931934c71ba3f (patch) | |
| tree | df2d4575988712fc262efb86f6d32ab184b021c2 | |
| parent | 6beb4ba1aaecb59fdfdc676434b5a3b17a4b5bfc (diff) | |
| download | rust-77f5da77a91af88130fcff3e726931934c71ba3f.tar.gz rust-77f5da77a91af88130fcff3e726931934c71ba3f.zip | |
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| -rw-r--r-- | src/libcollections/vec.rs | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/src/libcollections/vec.rs b/src/libcollections/vec.rs index ddab16493f0..4110faa41b3 100644 --- a/src/libcollections/vec.rs +++ b/src/libcollections/vec.rs @@ -1323,6 +1323,8 @@ impl<T> Drop for Vec<T> { // don't need unsafe_no_drop_flag shenanigans anymore. if self.buf.unsafe_no_drop_flag_needs_drop() { unsafe { + // The branch on needs_drop() is an -O1 performance optimization. + // Without the branch, dropping Vec<u8> takes linear time. if needs_drop::<T>() { for x in self.iter_mut() { drop_in_place(x); |