Update libc to 0.2.29
Cargo pulls in libc from crates.io for a number of dependencies, but 0.2.27 is too old to work properly with Solaris. In particular, it needs the change to make Solaris' `PTHREAD_PROCESS_PRIVATE` a 16-bit integer.
Cargo pulls in libc from crates.io for a number of dependencies, but
0.2.27 is too old to work properly with Solaris. In particular, it
needs the change to make Solaris' PTHREAD_PROCESS_PRIVATE a 16-bit
integer.
rustc::middle::dataflow - visit the CFG in RPO
We used to propagate bits in node-id order, which sometimes caused an
excessive number of iterations, especially when macros were present. As
everyone knows, visiting the CFG in RPO bounds the number of iterators
by 1 plus the depth of the most deeply nested loop (times the height of
the lattice, which is 1).
I have no idea how this affects borrowck perf in the non-worst-case, so it's probably a good idea to not roll this up so we can see the effects.
Fixes#43704.
r? @eddyb
We used to propagate bits in node-id order, which sometimes caused an
excessive number of iterations, especially when macros were present. As
everyone knows, visiting the CFG in RPO bounds the number of iterators
by 1 plus the depth of the most deeply nested loop (times the height of
the lattice, which is 1).
Fixes#43704.
de-orphan extended information
Bizarrely, librustc_passes, librustc_plugin, librustc_mir, and libsyntax [weren't getting their error explanations registered](https://github.com/rust-lang/rust/issues/35284) (leaving _several_ error codes absent from [the index](https://doc.rust-lang.org/nightly/error-index.html) and `--explain`). This surfaced a few latent doctest failures that were fixed where readily possible and ignored (with a recorded excuse) if not.
Also, we don't issue E0563 anymore.
r? @GuillaumeGomez
The sole appearance of this code was deleted in 6383de15; the existing practice
in these cases seems to be to comment out its mention in
`register_diagnostics!`.
After repatriating error explanations to the global registry, some lurking
doctest failures surfaced and needed to be chased down. Sadly, a few doctests
needed to be ignored due to a not-yet-understood regression in the doctest
`compile_fail` functionality (filed #43707).
Also reorder and space the list to make it clearer for futures updates
and to come closer to the original list.
Thanks @est31 for the instructions.
Fixes#43629.
r? @est31
Optimize initialization of arrays using repeat expressions
This PR was inspired by [this thread](https://www.reddit.com/r/rust/comments/6o8ok9/understanding_rust_performances_a_newbie_question/) on Reddit.
It tries to bring array initialization in the same ballpark as `Vec::from_elem()` for unoptimized builds.
For optimized builds this should relieve LLVM of having to figure out the construct we generate is in fact a `memset()`.
To that end this emits `llvm.memset()` when:
* the array is of integer type and all elements are zero (`Vec::from_elem()` also explicitly optimizes for this case)
* the array elements are byte sized
If the array is zero-sized initialization is omitted entirely.
