Vec::from_iter's general case allocates the vector up front;
this is redundant for the TrustedLen case, and can then be avoided
to reduce the size of the code.
Translate closures through the collector
Now that old trans is gone, there is no need for the hack of translating closures when they are instantiated. We can translate them like regular items.
r? @eddyb
Since I said "no intentional functional change" in the previous commit,
I guess it was inevitable there were unintentional changes. Not
functional, but optimization-wise. This restores the extend
specialization's use in Vec::from_iter.
to let people experiment with this target out of tree.
The MSP430 architecture is used in 16-bit microcontrollers commonly used
in Digital Signal Processing applications.
compile-test: allow overriding nodejs binary location
Add a command-line argument to manually specify which nodejs binary should be used,
which disables the default search.
Original work done by @tari.
Fixes#34188.
When compiling compiler-rt you typically compile with `-fvisibility=hidden`
which to ensure that all symbols are hidden in shared objects and don't show up
in symbol tables. This is important for these intrinsics being linked in every
crate to ensure that we're not unnecessarily bloating the public ABI of Rust
crates.
This should help allow the compiler-builtins project with Rust-defined builtins
start landing in-tree as well.
vec: Write the .extend() specialization in cleaner style
As far as possible, use regular `default fn` specialization in favour of
ad-hoc conditionals.
No intentional functional change. Code quality was validated against the same
benchmarks that were used in initial trusted len development.
This change is prompted by taking impressions from
https://github.com/rust-lang/rust/issues/27749#issuecomment-244498705
change the `box_free` lang item to accept pointers to unsized types
in miri we use the `box_free` lang item as the destructor for `Box` objects, since the function's api matches that of an `fn drop(&mut self)` in a hypothetical `impl<T: ?Sized> Drop for Box<T>` exactly.
This works fine except if we insert a check in the `size_of` intrinsic to ensure that it is only called with sized types, since the `box_free` lang item calls that intrinsic.
cc @eddyb
no clue who to r? here, probably lang team?
Avoid unnecessary mk_ty calls in Ty::super_fold_with.
This speeds up compilation of several rustc-benchmarks by 1--2% and the workload in #36799 by 5%.
r? @eddyb
std: Derive `Default` for `Duration`.
Discussed in #37546 the libs team reached the conclusion that a default zero
duration seems like a reasonable implementation of the `Default` trait.
Closes#37546
Remove one bounds check from BufReader
Very minor thing. Otherwise the optimizer can't be sure that pos <= cap. Added a paranoid debug_assert to ensure correctness instead.
CC #37573
On fmt string with unescaped `{` note how to escape
On cases of malformed format strings where a `{` hasn't been properly escaped, like `println!("{");`, present a NOTE explaining how to escape the `{` char.
Fix#34300.
Balance the debug output of Lvalue Subslice
The current debug output for Lvalue Subslice is not balanced and does not respect the comment[1], which indicates that we use `slice[from:-to] in Python terms.`. In python terms slices which have a start but no end are written as `a[start:]`, so following the comment, I fixed the output accordingly.
Grep-ing over the sources, I did not found any test cases checking this subslice debug output.
Note, I have not yet tested this change yet, as I am still waiting for the end of LLVM compilation.
[1] https://manishearth.github.io/rust-internals-docs/rustc/mir/enum.ProjectionElem.html