Fix stage 2 builds with a custom libdir.
When copying libstd for the stage 2 compiler, the builder ignores the
configured libdir/libdir_relative configuration parameters. This causes
the compiler to fail to find libstd, which cause any tools built with the
stage 2 compiler to fail.
To fix this, make the copy steps of rustbuild aware of the libdir_relative
parameter when the stage >= 2. Also update the dist target to be aware of
the new location of libstd.
Tidy: allow common lang+lib features
This allows changes to the Rust language that have both library
and language components share one feature gate.
The feature gates need to be "about the same change", so that both
library and language components must either be both unstable, or
both stable, and share the tracking issue.
Removes the ugly "proc_macro" exception added by #40939.
Closes#43089
Tells emcc to enable assertions and debugging information for
wasm32-experimental-emscripten. This makes the codegen issues caused by
LLVM bug 33824 manifest more frequently at runtime and improves the wasm
debugging experience.
Attempt to fix appveyor
This will fix the problem, I think, but I don't know that this is a good idea (potentially leaving ourselves open to attackers, I guess, if a cert was revoked...). Of course, it may not. I don't actually have windows to check on..
r? @alexcrichton
Add support for full RELRO
This commit adds support for full RELRO, and enables it for the
platforms I know have support for it.
Full RELRO makes the PLT+GOT data read-only on startup, preventing it
from being overwritten.
http://tk-blog.blogspot.com/2009/02/relro-not-so-well-known-memory.htmlFixesrust-lang/rust#29877.
---
I'm not entirely certain if this is the best way to do it, but I figured mimicking the way it's done for PIE seemed like a good start at least. I'm not sure whether we want to have it enabled by default globally and then disabling it explicitly for targets that don't support it though. I'm also not sure whether the `full_relro` function should call `bug!()` or something like it for linkers that don't support it rather than no-opping.
Slew of builtin-attribute gating tests
Slew of builtin-attribute "gating" tests for issue #43106.
Some stray observations:
* I don't know if its a good thing that so many attributes allow inputs which are silently discarded. (I made heavy use of that in writing my tests, but that was more out of curiosity than necessity.)
* The difference between crate-level and non-crate-level behavior is quite significant in some cases. Definitely worth making sure one has tests for both cases. (Not as clear whether it was worthwhile trying the various other AST forms like `fn f()` vs `struct S;`)
* `#[no_builtins]` and `#[no_mangle]` occur twice on the `BUILTIN_ATTRIBUTES` list. Thats almost certainly a bug. (Filed as #43148)
* We are maximally liberal in what we allow for `#[test]` and `#[bench]` when one compiles without `--test`.
* We allow `#[no_mangle]` on arbitrary AST nodes, but only warn about potential misuse on `fn`
* We allow `#[cold]`, `#[must_use]`, `#[windows_subsystem]`, and `#[no_builtins]` on arbitrary AST nodes. I don't know off-hand what the semantics are for e.g. a `#[cold] type T = ...;`
* We allow crate-level `#![inline]`. That's probably a bug since its otherwise restricted to `fn` items
Unify rules about commas in match arms and semicolons in expressions
Original discussion: https://internals.rust-lang.org/t/syntax-of-block-like-expressions-in-match-arms/5025/7.
Currently, rust uses different rules to determine if `,` is needed after an expression in a match arm and if `;` is needed in an expression statement:
```Rust
fn stmt() {
# no need for semicolons
{ () }
if true { () } else { () }
loop {}
while true {}
}
fn match_arm(n: i32) {
match n {
1 => { () } # can omit comma here
2 => if true { () } else { () }, # but all other cases do need commas.
3 => loop { },
4 => while true {},
_ => ()
}
}
```
This seems weird: why would you want to require `,` after and `if`?
This PR unifies the rules. It is backwards compatible because it allows strictly more programs.
float_bits_conv made it into 1.20
It seems that my PR to stabilize the `float_bits_conv` feature got merged before beta branched, which means I'm lucky, and the stabilization makes it into Rust 1.20. As it was against my expectations, the version number has to be corrected from 1.21 to 1.20.
Please also apply this PR to the beta branch.
