add `-C overflow-checks` option
In addition to defining and handling the new option, we also add a method on librustc::Session for determining the necessity of overflow checks. This method provides a single point to sort out the three (!) different ways for turning on overflow checks: -C debug-assertions, -C overflow-checks, and -Z force-overflow-checks.
I was seeing a [run-pass/issue-28950.rs](b1363a73ed/src/test/run-pass/issue-28950.rs) failure on my machine with these patches, but I was also seeing the failure without the changes to the core compiler. We'll see what travis says.
Fixes#33134. r? @alexcrichton
Fix indentation of error message
So I just encountered this error for the first time. It's unclear what
it means, why I encountered it, or how to fix it. But worst of all, it
has a random newline and weird indentation! This commit fixes that last
bit.
<img width="680" alt="screen shot 2017-02-18 at 4 35 36 pm" src="https://cloud.githubusercontent.com/assets/1529387/23097087/0ef5ac4a-f5f9-11e6-9132-18ce759f7092.png">
In addition to defining and handling the new option, we also add a
method on librustc::Session for determining the necessity of overflow
checks. This method provides a single point to sort out the three (!)
different ways for turning on overflow checks: -C debug-assertions, -C
overflow-checks, and -Z force-overflow-checks.
Fixes#33134.
Report full details of inference errors
When the old suggestion machinery was removed by @brson in https://github.com/rust-lang/rust/pull/37057, it was not completely removed. There was a bit of code that had the job of going through errors and finding those for which suggestions were applicable, and it remained, causing us not to emit the full details of such errors. This PR removes that.
I've also added various lifetime tests to the UI test suite (so you can also see the before/after there). I have some concrete thoughts on how to improve these cases and am planning on writing those up in some mentoring issues (@CengizIO has expressed interest in working on those changes, so I plan to work with him on it, at least to start).
cc @jonathandturner
So I just encountered this error for the first time. It's unclear what
it means, why I encountered it, or how to fix it. But worst of all, it
has a random newline and weird indentation! This commit fixes that last
bit.
erase late bound regions in `get_vtable_methods()`
Higher-ranked object types can otherwise cause late-bound regions to
sneak into the substs, leading to the false conclusion that some method
is unreachable.
r? @arielb1, who wrote the heart of this patch anyhow
Fixes#39292
[MIR] Make InlineAsm a Statement
Previously InlineAsm was an Rvalue, but its semantics doesn't really match the semantics of an
Rvalue - rather it behaves more like a Statement.
r? @nikomatsakis you wanted this to happen
Higher-ranked object types can otherwise cause late-bound regions to
sneak into the substs, leading to the false conclusion that some method
is unreachable. The heart of this patch is from @arielb1.
[MIR] SwitchInt Everywhere
Something I've been meaning to do for a very long while. This PR essentially gets rid of 3 kinds of conditional branching and only keeps the most general one - `SwitchInt`. Primary benefits are such that dealing with MIR now does not involve dealing with 3 different ways to do conditional control flow. On the other hand, constructing a `SwitchInt` currently requires more code than what previously was necessary to build an equivalent `If` terminator. Something trivially "fixable" with some constructor methods somewhere (MIR needs stuff like that badly in general).
Some timings (tl;dr: slightly faster^1 (unexpected), but also uses slightly more memory at peak (expected)):
^1: Not sure if the speed benefits are because of LLVM liking the generated code better or the compiler itself getting compiled better. Either way, its a net benefit. The CORE and SYNTAX timings done for compilation without optimisation.
```
AFTER:
Building stage1 std artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 31.50 secs
Finished release [optimized] target(s) in 31.42 secs
Building stage1 compiler artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 439.56 secs
Finished release [optimized] target(s) in 435.15 secs
CORE: 99% (24.81 real, 0.13 kernel, 24.57 user); 358536k resident
CORE: 99% (24.56 real, 0.15 kernel, 24.36 user); 359168k resident
SYNTAX: 99% (49.98 real, 0.48 kernel, 49.42 user); 653416k resident
SYNTAX: 99% (50.07 real, 0.58 kernel, 49.43 user); 653604k resident
BEFORE:
Building stage1 std artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 31.84 secs
Building stage1 compiler artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 451.17 secs
CORE: 99% (24.66 real, 0.20 kernel, 24.38 user); 351096k resident
CORE: 99% (24.36 real, 0.17 kernel, 24.18 user); 352284k resident
SYNTAX: 99% (52.24 real, 0.56 kernel, 51.66 user); 645544k resident
SYNTAX: 99% (51.55 real, 0.48 kernel, 50.99 user); 646428k resident
```
cc @nikomatsakis @eddyb
