diff options
| -rw-r--r-- | compiler/rustc_feature/src/lib.rs | 19 | ||||
| -rw-r--r-- | compiler/rustc_feature/src/tests.rs | 12 | ||||
| -rw-r--r-- | compiler/rustc_feature/src/unstable.rs | 2 | ||||
| -rw-r--r-- | tests/ui/bootstrap/rustc_bootstap.force_stable.stderr | 10 | ||||
| -rw-r--r-- | tests/ui/bootstrap/rustc_bootstap.rs | 47 |
5 files changed, 81 insertions, 9 deletions
diff --git a/compiler/rustc_feature/src/lib.rs b/compiler/rustc_feature/src/lib.rs index 9f42d3ec45c..5d27b8f542c 100644 --- a/compiler/rustc_feature/src/lib.rs +++ b/compiler/rustc_feature/src/lib.rs @@ -74,14 +74,19 @@ impl UnstableFeatures { // Returns whether `krate` should be counted as unstable let is_unstable_crate = |var: &str| krate.is_some_and(|name| var.split(',').any(|new_krate| new_krate == name)); - // `true` if we should enable unstable features for bootstrapping. - let bootstrap = - std::env::var("RUSTC_BOOTSTRAP").is_ok_and(|var| var == "1" || is_unstable_crate(&var)); - match (disable_unstable_features, bootstrap) { - (_, true) => UnstableFeatures::Cheat, - (true, _) => UnstableFeatures::Disallow, - (false, _) => UnstableFeatures::Allow, + + let bootstrap = std::env::var("RUSTC_BOOTSTRAP").ok(); + if let Some(val) = bootstrap.as_deref() { + match val { + val if val == "1" || is_unstable_crate(val) => return UnstableFeatures::Cheat, + // Hypnotize ourselves so that we think we are a stable compiler and thus don't + // allow any unstable features. + "-1" => return UnstableFeatures::Disallow, + _ => {} + } } + + if disable_unstable_features { UnstableFeatures::Disallow } else { UnstableFeatures::Allow } } pub fn is_nightly_build(&self) -> bool { diff --git a/compiler/rustc_feature/src/tests.rs b/compiler/rustc_feature/src/tests.rs index 50433e44b13..cc0e1f31209 100644 --- a/compiler/rustc_feature/src/tests.rs +++ b/compiler/rustc_feature/src/tests.rs @@ -18,6 +18,16 @@ fn rustc_bootstrap_parsing() { assert!(!is_bootstrap("x,y,z", Some("a"))); assert!(!is_bootstrap("x,y,z", None)); - // this is technically a breaking change, but there are no stability guarantees for RUSTC_BOOTSTRAP + // `RUSTC_BOOTSTRAP=0` is not recognized. assert!(!is_bootstrap("0", None)); + + // `RUSTC_BOOTSTRAP=-1` is force-stable, no unstable features allowed. + let is_force_stable = |krate| { + std::env::set_var("RUSTC_BOOTSTRAP", "-1"); + matches!(UnstableFeatures::from_environment(krate), UnstableFeatures::Disallow) + }; + assert!(is_force_stable(None)); + // Does not support specifying any crate. + assert!(is_force_stable(Some("x"))); + assert!(is_force_stable(Some("x,y,z"))); } diff --git a/compiler/rustc_feature/src/unstable.rs b/compiler/rustc_feature/src/unstable.rs index 8326d0031ea..a67a5776449 100644 --- a/compiler/rustc_feature/src/unstable.rs +++ b/compiler/rustc_feature/src/unstable.rs @@ -54,7 +54,7 @@ pub struct EnabledLangFeature { pub stable_since: Option<Symbol>, } -/// Information abhout an enabled library feature. +/// Information about an enabled library feature. #[derive(Debug, Copy, Clone)] pub struct EnabledLibFeature { pub gate_name: Symbol, diff --git a/tests/ui/bootstrap/rustc_bootstap.force_stable.stderr b/tests/ui/bootstrap/rustc_bootstap.force_stable.stderr new file mode 100644 index 00000000000..f378f3c70dd --- /dev/null +++ b/tests/ui/bootstrap/rustc_bootstap.force_stable.stderr @@ -0,0 +1,10 @@ +error: the option `Z` is only accepted on the nightly compiler + +help: consider switching to a nightly toolchain: `rustup default nightly` + +note: selecting a toolchain with `+toolchain` arguments require a rustup proxy; see <https://rust-lang.github.io/rustup/concepts/index.html> + +note: for more information about Rust's stability policy, see <https://doc.rust-lang.org/book/appendix-07-nightly-rust.html#unstable-features> + +error: 1 nightly option were parsed + diff --git a/tests/ui/bootstrap/rustc_bootstap.rs b/tests/ui/bootstrap/rustc_bootstap.rs new file mode 100644 index 00000000000..3d792ef4be4 --- /dev/null +++ b/tests/ui/bootstrap/rustc_bootstap.rs @@ -0,0 +1,47 @@ +//! Check `RUSTC_BOOTSTRAP`'s behavior in relation to feature stability and what rustc considers +//! itself to be (stable vs non-stable ). +//! +//! `RUSTC_BOOTSTRAP` accepts: +//! +//! - `1`: cheat, allow usage of unstable features even if rustc thinks it is a stable compiler. +//! - `x,y,z`: comma-delimited list of crates. +//! - `-1`: force rustc to think it is a stable compiler. + +// ignore-tidy-linelength + +//@ revisions: default_nightly cheat cheat_single_crate cheat_multi_crate force_stable invalid_zero invalid_junk +//@ only-nightly + +//@[default_nightly] unset-rustc-env:RUSTC_BOOTSTRAP +//@[default_nightly] check-pass + +// For a nightly compiler, this is same as `default_nightly` as if `RUSTC_BOOTSTRAP` was unset. +//@[invalid_zero] rustc-env:RUSTC_BOOTSTRAP=0 +//@[invalid_zero] check-pass + +// Invalid values are silently discarded, same as `default_nightly`, i.e. as if `RUSTC_BOOTSTRAP` +// was unset. +//@[invalid_junk] rustc-env:RUSTC_BOOTSTRAP=* +//@[invalid_junk] check-pass + +//@[cheat] rustc-env:RUSTC_BOOTSTRAP=1 +//@[cheat] check-pass + +//@[cheat_single_crate] rustc-env:RUSTC_BOOTSTRAP=x +//@[cheat_single_crate] check-pass + +//@[cheat_multi_crate] rustc-env:RUSTC_BOOTSTRAP=x,y,z +//@[cheat_multi_crate] check-pass + +// Note: compiletest passes some `-Z` flags to the compiler for ui testing purposes, so here we +// instead abuse the fact that `-Z unstable-options` is also part of rustc's stability story and is +// also affected by `RUSTC_BOOTSTRAP`. +//@[force_stable] rustc-env:RUSTC_BOOTSTRAP=-1 +//@[force_stable] compile-flags: -Z unstable-options +//@[force_stable] regex-error-pattern: error: the option `Z` is only accepted on the nightly compiler + +#![crate_type = "lib"] + +// Note: `rustc_attrs` is a perma-unstable internal feature that is unlikely to change, which is +// used as a proxy to check `RUSTC_BOOTSTRAP` versus stability checking logic. +#![feature(rustc_attrs)] |