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| author | bors <bors@rust-lang.org> | 2013-06-16 00:58:09 -0700 |
|---|---|---|
| committer | bors <bors@rust-lang.org> | 2013-06-16 00:58:09 -0700 |
| commit | d1927d295013e19e57a9773c37ded698e89392eb (patch) | |
| tree | bfb6e89eb9b408ca5069f8b14b56551971f9d9a8 /src/libstd | |
| parent | f74e1935aa55aff7ecf9ac75a5114a7b41d4e56f (diff) | |
| parent | ac83f4b7325eea6ec82db73fb5c1ece7d8320908 (diff) | |
| download | rust-d1927d295013e19e57a9773c37ded698e89392eb.tar.gz rust-d1927d295013e19e57a9773c37ded698e89392eb.zip | |
auto merge of #7137 : erickt/rust/from-elem-fixme, r=thestinger
This is to make sure we track optimizing `vec::from_elem`.
Diffstat (limited to 'src/libstd')
| -rw-r--r-- | src/libstd/vec.rs | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/src/libstd/vec.rs b/src/libstd/vec.rs index 7b4764164b5..f330e13c5bd 100644 --- a/src/libstd/vec.rs +++ b/src/libstd/vec.rs @@ -146,8 +146,10 @@ pub fn from_fn<T>(n_elts: uint, op: old_iter::InitOp<T>) -> ~[T] { * to the value `t`. */ pub fn from_elem<T:Copy>(n_elts: uint, t: T) -> ~[T] { - // hack: manually inline from_fn for 2x plus speedup (sadly very important, from_elem is a - // bottleneck in borrowck!) + // FIXME (#7136): manually inline from_fn for 2x plus speedup (sadly very + // important, from_elem is a bottleneck in borrowck!). Unfortunately it + // still is substantially slower than using the unsafe + // vec::with_capacity/ptr::set_memory for primitive types. unsafe { let mut v = with_capacity(n_elts); do as_mut_buf(v) |p, _len| { |