Stabilize the loop_break_value feature

[pietroalbini]

Tracking issue: #37339.

Documentation PRs already sent to the various repositories.

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @pnkfelix (or someone else) soon.

If any changes to this PR are deemed necessary, please add them as extra commits. This ensures that the reviewer can see what has changed since they last reviewed the code. Due to the way GitHub handles out-of-date commits, this should also make it reasonably obvious what issues have or haven't been addressed. Large or tricky changes may require several passes of review and changes.

Please see the contribution instructions for more information.

[arielb1]

I think you forgot to update the tests:

[00:38:10] ---- [compile-fail] compile-fail/feature-gate-loop-break-value.rs stdout ----

[00:38:10] 	

[00:38:10] error: /checkout/src/test/compile-fail/feature-gate-loop-break-value.rs:13: unexpected "error": '13:15: 13:18: mismatched types [E0308]'

[00:38:10] 

[00:38:10] error: /checkout/src/test/compile-fail/feature-gate-loop-break-value.rs:13: expected error not found: `break` with a value is experimental

[00:38:10] 

[00:38:10] error: 1 unexpected errors found, 1 expected errors not found

[00:38:10] status: exit code: 101

[00:38:10] command: /checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc /checkout/src/test/compile-fail/feature-gate-loop-break-value.rs -L /checkout/obj/build/x86_64-unknown-linux-gnu/test/compile-fail --target=x86_64-unknown-linux-gnu --error-format json -L /checkout/obj/build/x86_64-unknown-linux-gnu/test/compile-fail/feature-gate-loop-break-value.stage2-x86_64-unknown-linux-gnu.compile-fail.libaux -C prefer-dynamic -o /checkout/obj/build/x86_64-unknown-linux-gnu/test/compile-fail/feature-gate-loop-break-value.stage2-x86_64-unknown-linux-gnu -Crpath -O -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers

[00:38:10] unexpected errors (from JSON output): [

[00:38:10]     Error {

[00:38:10]         line_num: 13,

[00:38:10]         kind: Some(

[00:38:10]             Error

[00:38:10]         ),

[00:38:10]         msg: "13:15: 13:18: mismatched types [E0308]"

[00:38:10]     }

[00:38:10] ]

[00:38:10] 

[00:38:10] not found errors (from test file): [

[00:38:10]     Error {

[00:38:10]         line_num: 13,

[00:38:10]         kind: Some(

[00:38:10]             Error

[00:38:10]         ),

[00:38:10]         msg: "`break` with a value is experimental"

[00:38:10]     }

[00:38:10] ]

[00:38:10] 

[00:38:10] thread '[compile-fail] compile-fail/feature-gate-loop-break-value.rs' panicked at 'explicit panic', /checkout/src/tools/compiletest/src/runtest.rs:1129

[00:38:10] note: Run with `RUST_BACKTRACE=1` for a backtrace.

[pietroalbini]

Woops! Removed that test.

[bors]

☔ The latest upstream changes (presumably #41857) made this pull request unmergeable. Please resolve the merge conflicts.

[pietroalbini]

Seems like the reviewer is taking some time off.

r? @nikomatsakis

[nikomatsakis]

@bors r+

[bors]

📌 Commit 93c1f24 has been approved by nikomatsakis

[nikomatsakis]

@pietroalbini thanks! Sorry for the delay, I've been traveling. This looks good though.

[bors]

⌛ Testing commit 93c1f24 with merge 5eafa87...

[bors]

💔 Test failed - status-travis

[pietroalbini]

Ugh. Something received SIGSEGV while testing the standard library I guess. Is this a random failure?

[01:01:32] Testing libstd stage2 (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-musl)
{snip}
[01:04:32] error: process didn't exit successfully: `/checkout/obj/build/x86_64-unknown-linux-gnu/stage2-std/x86_64-unknown-linux-musl/release/deps/std-116dfe5a1b0286e7` (signal: 11, SIGSEGV: invalid memory reference)
[01:04:32] 
[01:04:32] To learn more, run the command again with --verbose.
[01:04:32] 
[01:04:32] 
[01:04:32] command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/cargo" "test" "-j" "4" "--target" "x86_64-unknown-linux-musl" "--release" "--locked" "--manifest-path" "/checkout/src/libstd/Cargo.toml" "--features" "panic-unwind jemalloc backtrace" "-p" "std:0.0.0" "-p" "libc:0.0.0" "-p" "rustc_lsan:0.0.0" "-p" "collections:0.0.0" "-p" "unwind:0.0.0" "-p" "rustc_msan:0.0.0" "-p" "rustc_tsan:0.0.0" "-p" "alloc_system:0.0.0" "-p" "compiler_builtins:0.0.0" "-p" "std_unicode:0.0.0" "-p" "rustc_asan:0.0.0" "-p" "rand:0.0.0" "-p" "core:0.0.0" "-p" "panic_abort:0.0.0" "-p" "alloc:0.0.0" "--"
[01:04:32] expected success, got: exit code: 101

[Mark-Simulacrum]

Yeah, that's #38618.

@bors retry