bors [Tue, 19 May 2015 01:08:54 +0000 (01:08 +0000)]
Auto merge of #25441 - alexcrichton:debug-panic-neg, r=aturon
Debug overflow checks for arithmetic negation landed in #24500, at which time
the `abs` method on signed integers was changed to using `wrapping_neg` to
ensure that the function never panicked. This implied that `abs` of `INT_MIN`
would return `INT_MIN`, another negative value. When this change was back-ported
to beta, however, in #24708, the `wrapping_neg` function had not yet been
backported, so the implementation was changed in #24785 to `!self + 1`. This
change had the unintended side effect of enabling debug overflow checks for the
`abs` function. Consequently, the current state of affairs is that the beta
branch checks for overflow in debug mode for `abs` and the nightly branch does
not.
This commit alters the behavior of nightly to have `abs` always check for
overflow in debug mode. This change is more consistent with the way the standard
library treats overflow as well, and it is also not a breaking change as it's
what the beta branch currently does (albeit if by accident).
Alex Crichton [Fri, 15 May 2015 16:18:14 +0000 (09:18 -0700)]
std: Make abs() panic on overflow in debug mode
Debug overflow checks for arithmetic negation landed in #24500, at which time
the `abs` method on signed integers was changed to using `wrapping_neg` to
ensure that the function never panicked. This implied that `abs` of `INT_MIN`
would return `INT_MIN`, another negative value. When this change was back-ported
to beta, however, in #24708, the `wrapping_neg` function had not yet been
backported, so the implementation was changed in #24785 to `!self + 1`. This
change had the unintended side effect of enabling debug overflow checks for the
`abs` function. Consequently, the current state of affairs is that the beta
branch checks for overflow in debug mode for `abs` and the nightly branch does
not.
This commit alters the behavior of nightly to have `abs` always check for
overflow in debug mode. This change is more consistent with the way the standard
library treats overflow as well, and it is also not a breaking change as it's
what the beta branch currently does (albeit if by accident).
bors [Mon, 18 May 2015 23:29:26 +0000 (23:29 +0000)]
Auto merge of #25337 - bleibig:update-grammar, r=nikomatsakis
* Correctly lex CRLF in string literals
* Update `extern CRATE as NAME` syntax
* Allow leading `::` in view paths
* Allow TySums in type ascriptions and impls
* Allow macros to have visibility and attributes
* Update syntax for qualified path types and expressions
* Allow block expressions to be called () and indexed []
bors [Mon, 18 May 2015 19:54:24 +0000 (19:54 +0000)]
Auto merge of #25230 - rayglover:patch-bitset, r=Gankro
Some modest running-time improvements to `std::collections::BitSet` on bit-sets of varying set-membership densities. This is work originally from [here](https://github.com/rayglover/alt_collections). (Benchmarks copied below)
```
std::collections::BitSet / alt_collections::BitSet
Rollup merge of #25537 - carols10cents:grammar-oops, r=alexcrichton
Hiiii soooo I'm trying to get the reference grammar and associated tests running again, and I swear I tested before but I must have had multiple things going on when I did, because the change I made in #25137 to verify.rs is totally wrong. The RustLexer.tokens file that antlr generates has two sections:
and verify.rs is only interested in the first half-- the `continue` is to ignore the second half. In 9c7d5ae, I made it panic instead. I was trying to make sure verify.rs handled everything that might happen in the first half and complain if it didn't. That would mean the reference grammar was out of sync with at least verify.rs, if not the real grammar. But it's totally ok for verify.rs to not handle the entire second half of the file.
I'm sorry for breaking this :( Good thing these tests aren't being run regularly yet...? :flushed:
Rollup merge of #25530 - peferron:doc-closures-whitespace-fix, r=alexcrichton
Tiny fixes collected while reading through the Rust book. If they're too nitpicky please let me know and I'll ignore the next ones. :)
The spaces after the function and closure arguments might be intentional, but they do not make much sense: the usual formatting doesn't have such spaces, and they aren't helping align the three lines together either.
r? @steveklabnik (as suggested by [CONTRIBUTING.md](https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.md))
bors [Sun, 17 May 2015 23:53:41 +0000 (23:53 +0000)]
Auto merge of #25527 - inrustwetrust:const-not-overflow, r=alexcrichton
Fixes #23968.
Since the values are stored in a u64 internally, we need to be mask away the
high bits after applying the ! operator. Otherwise, these bits will be set to
one, causing overflow.
bors [Sun, 17 May 2015 22:13:30 +0000 (22:13 +0000)]
Auto merge of #25523 - nham:remove_E0068, r=alexcrichton
A built-in feature enabling the dereferencing of newtype structs was removed
in PR https://github.com/rust-lang/rust/pull/11188, and this error (E0068) was added at the same time to warn of
its removal. It seems to make sense to remove the error now, given that
the obsolete feature it is warning about was removed nearly a year and a
half ago.
This was wrong... the `continue` was to ignore the latter half of the
tokens file. Another mechanism will have to be used to keep the model
grammar's tokens in sync with the actual grammar's tokens :-/
inrustwetrust [Sun, 17 May 2015 08:04:15 +0000 (10:04 +0200)]
Fix compile-time integer overflow when using ! on unsigned values
Since the values are stored in a u64 internally, we need to be mask away the
high bits after applying the ! operator. Otherwise, these bits will be set to
one, causing overflow.
Rollup merge of #25472 - WillEngler:book-tiny-typo-fixes, r=alexcrichton
This PR fixes two little typos in the Dining Philosophers example.
Also, there are two style points that may have been oversights but may have been deliberate, so I'll just bring them up here:
1) In the last paragraph, you say
> You’ll notice we can introduce a new binding to `table` here, and it will shadow the old one. This is often used so that you don’t need to come up with two unique names.
You already said something similar to this in the Guessing Game, but maybe you intended for this example to be independent of that one.
2) In "Rust Inside Other Languages," you introduce the idea of the "global interpreter lock" and then refer to it as the GIL a few paragraphs later without explicitly stating that GIL == global interpreter lock. It's reasonable to expect readers to make the connection, but maybe that's not what you intended.
Nick Hamann [Sun, 17 May 2015 06:12:11 +0000 (01:12 -0500)]
Remove error about obsolete dereferencing of newtype structs.
A built-in feature enabling the dereferencing of newtype structs was removed
in PR #11188, and this error (E0068) was added at the same time to warn of
its removal. It seems to make sense to remove the error now, given that
the obsolete feature it is warning about was removed nearly a year and a
half ago.
bors [Sat, 16 May 2015 19:17:30 +0000 (19:17 +0000)]
Auto merge of #25434 - dotdash:gep, r=alexcrichton
Using regular pointer arithmetic to iterate collections of zero-sized types
doesn't work, because we'd get the same pointer all the time. Our
current solution is to convert the pointer to an integer, add an offset
and then convert back, but this inhibits certain optimizations.
What we should do instead is to convert the pointer to one that points
to an i8\*, and then use a LLVM GEP instructions without the inbounds
flag to perform the pointer arithmetic. This allows to generate pointers
that point outside allocated objects without causing UB (as long as you
don't dereference them), and it wraps around using two's complement,
i.e. it behaves exactly like the wrapping_* operations we're currently
using, with the added benefit of LLVM being able to better optimize the
resulting IR.
bors [Sat, 16 May 2015 08:37:31 +0000 (08:37 +0000)]
Auto merge of #25453 - jimblandy:FQA-fiasco-link, r=alexcrichton
Fix the link to the "static initialization order fiasco" discussion in the C++ Frequently Questioned Answers.
At present the link points to a mail message summarizing the decision not to have resumable exceptions, but the FAQ means to refer to a discussion of the "static initialization order fiasco". I've made my best guess at what it meant to refer to.
bors [Sat, 16 May 2015 02:11:11 +0000 (02:11 +0000)]
Auto merge of #25440 - durka:patch-3, r=alexcrichton
The Traits chapter uses "adding methods to `int`" as an example of "something bad", but there is no such thing as `int` anymore, right? So I changed it to `i32`.
bors [Fri, 15 May 2015 21:17:42 +0000 (21:17 +0000)]
Auto merge of #25437 - MazinZ1:master, r=alexcrichton
The download links of Windows installers on the Nightly Rust page are using beta builds instead of nightly builds, which caused some confusions when I was setting up my env. Probably it's better to use the links of nightly builds here.
Alex Burka [Fri, 15 May 2015 16:14:39 +0000 (12:14 -0400)]
trpl: change from "int" to "i32" in Traits
The Traits chapter uses "adding methods to `int`" as an example of "something bad", but there is no such thing as `int` anymore, right? So I changed it to `i32`.
bors [Fri, 15 May 2015 15:14:25 +0000 (15:14 +0000)]
Auto merge of #25059 - erickt:pprint, r=acrichto
The recent quote changes unfortunately broke unquoting statements like `let foo = 5` because the parser requires their to be a trailing semicolon in those statements. Along the way I added support for unquoting generics and where clauses as well as better pretty printing of `token::Interpolated`.
Z1 [Fri, 15 May 2015 14:52:47 +0000 (10:52 -0400)]
Fix download links of Nightly Windows installers
The download links of Windows installers on the Nightly Rust page are using beta builds instead of nightly builds, which caused some confusions when I was setting up my env. Probably it's better to use the links of nightly builds here.
Björn Steinbrink [Fri, 15 May 2015 13:20:42 +0000 (15:20 +0200)]
Allow for better optimizations of iterators for zero-sized types
Using regular pointer arithmetic to iterate collections of zero-sized types
doesn't work, because we'd get the same pointer all the time. Our
current solution is to convert the pointer to an integer, add an offset
and then convert back, but this inhibits certain optimizations.
What we should do instead is to convert the pointer to one that points
to an i8*, and then use a LLVM GEP instructions without the inbounds
flag to perform the pointer arithmetic. This allows to generate pointers
that point outside allocated objects without causing UB (as long as you
don't dereference them), and it wraps around using two's complement,
i.e. it behaves exactly like the wrapping_* operations we're currently
using, with the added benefit of LLVM being able to better optimize the
resulting IR.