The code was using (in the notation of Doornik 2005) `f(x_{i+1}) -
f(x_{i+2})` rather than `f(x_i) - f(x_{i+1})`. This corrects that, and
removes the F_DIFF tables which caused this problem in the first place.
They `F_DIFF` tables are a micro-optimisation (in theory, they could
easily be a micro-pessimisation): that `if` gets hit about 1% of the
time for Exp/Normal, and the rest of the condition involves RNG calls
and a floating point `exp`, so it is unlikely that saving a single FP
subtraction will be very useful (especially as more tables means more
memory reads and higher cache pressure, as well as taking up space in
the binary (although only ~2k in this case)).
Closes#10084. Notably, unlike that issue suggests, this wasn't a
problem with the Exp tables. It affected Normal too, but since it is
symmetric, there was no bias in the mean (as the bias was equal on the
positive and negative sides and so cancelled out) but it was visible as
a variance slightly lower than it should be.
- `begin_unwind` and `fail!` is now generic over any `T: Any + Send`.
- Every value you fail with gets boxed as an `~Any`.
- Because of implementation issues, `&'static str` and `~str` are still
handled specially behind the scenes.
- Changed the big macro source string in libsyntax to a raw string
literal, and enabled doc comments there.
- `begin_unwind` is now generic over any `T: Any + Send`.
- Every value you fail with gets boxed as an `~Any`.
- Because of implementation details, `&'static str` and `~str` are still
handled specially behind the scenes.
- Changed the big macro source string in libsyntax to a raw string
literal, and enabled doc comments there.
Allows an enum with a discriminant to use any of the primitive integer types to store it. By default the smallest usable type is chosen, but this can be overridden with an attribute: `#[repr(int)]` etc., or `#[repr(C)]` to match the target's C ABI for the equivalent C enum.
Also adds a lint pass for using non-FFI safe enums in extern declarations, checks that specified discriminants can be stored in the specified type if any, and fixes assorted code that was assuming int.
This is one of the final steps needed to complete #9128. It still needs a little bit of polish before closing that issue, but it's in a pretty much "done" state now.
The idea here is that the entire event loop implementation using libuv is now housed in `librustuv` as a completely separate library. This library is then injected (via `extern mod rustv`) into executable builds (similarly to how libstd is injected, tunable via `#[no_uv]`) to bring in the "rust blessed event loop implementation."
Codegen-wise, there is a new `event_loop_factory` language item which is tagged on a function with 0 arguments returning `~EventLoop`. This function's symbol is then inserted into the crate map for an executable crate, and if there is no definition of the `event_loop_factory` language item then the value is null.
What this means is that embedding rust as a library in another language just got a little harder. Libraries don't have crate maps, which means that there's no way to find the event loop implementation to spin up the runtime. That being said, it's always possible to build the runtime manually. This request also makes more runtime components public which should probably be public anyway. This new public-ness should allow custom scheduler setups everywhere regardless of whether you follow the `rt::start `path.
The actual fix would be to make rustpkg use `rustc::monitor` so it picks
up anything special that rustc needs, but for now let's keep the tests
from breaking.
The previous implementation, when combined with small discriminants and
immediate types, caused problems for types like `Either<u8, i16>` which
are now small enough to be immediate and can have fields intersecting
the highest-alignment variant's alignment padding (which LLVM doesn't
preserve). So let's not do that.
Otherwise, run-pass/deriving-primitive.rs breaks on 32-bit platforms,
because `int::min_value` is `0xffffffff7fffffff` when evaluated for the
discriminant declaration.
Not only can discriminants be smaller than int now, but they can be
larger than int on 32-bit targets. This has obvious implications for the
reflection interface. Without this change, things fail with LLVM
assertions when we try to "extend" i64 to i32.
