diff --git a/compiler/rustc_lint/src/builtin.rs b/compiler/rustc_lint/src/builtin.rs index c290462fc20ba..2c9d212a6a64d 100644 --- a/compiler/rustc_lint/src/builtin.rs +++ b/compiler/rustc_lint/src/builtin.rs @@ -58,6 +58,7 @@ use rustc_middle::lint::in_external_macro; use rustc_middle::ty::layout::LayoutOf; use rustc_middle::ty::print::with_no_trimmed_paths; use rustc_middle::ty::GenericArgKind; +use rustc_middle::ty::ToPredicate; use rustc_middle::ty::TypeVisitableExt; use rustc_middle::ty::{self, Ty, TyCtxt, VariantDef}; use rustc_session::config::ExpectedValues; @@ -68,6 +69,7 @@ use rustc_span::symbol::{kw, sym, Ident, Symbol}; use rustc_span::{BytePos, InnerSpan, Span}; use rustc_target::abi::Abi; use rustc_trait_selection::infer::{InferCtxtExt, TyCtxtInferExt}; +use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt as _; use rustc_trait_selection::traits::{self, misc::type_allowed_to_implement_copy}; use crate::nonstandard_style::{method_context, MethodLateContext}; @@ -673,6 +675,9 @@ impl<'tcx> LateLintPass<'tcx> for MissingCopyImplementations { if ty.is_copy_modulo_regions(cx.tcx, param_env) { return; } + if type_implements_negative_copy_modulo_regions(cx.tcx, ty, param_env) { + return; + } // We shouldn't recommend implementing `Copy` on stateful things, // such as iterators. @@ -708,6 +713,24 @@ impl<'tcx> LateLintPass<'tcx> for MissingCopyImplementations { } } +/// Check whether a `ty` has a negative `Copy` implementation, ignoring outlives constraints. +fn type_implements_negative_copy_modulo_regions<'tcx>( + tcx: TyCtxt<'tcx>, + ty: Ty<'tcx>, + param_env: ty::ParamEnv<'tcx>, +) -> bool { + let trait_ref = ty::TraitRef::new(tcx, tcx.require_lang_item(hir::LangItem::Copy, None), [ty]); + let pred = ty::TraitPredicate { trait_ref, polarity: ty::ImplPolarity::Negative }; + let obligation = traits::Obligation { + cause: traits::ObligationCause::dummy(), + param_env, + recursion_depth: 0, + predicate: ty::Binder::dummy(pred).to_predicate(tcx), + }; + + tcx.infer_ctxt().build().predicate_must_hold_modulo_regions(&obligation) +} + declare_lint! { /// The `missing_debug_implementations` lint detects missing /// implementations of [`fmt::Debug`] for public types. diff --git a/library/core/src/clone.rs b/library/core/src/clone.rs index a6d6230d3a62b..d7ca9c22dada8 100644 --- a/library/core/src/clone.rs +++ b/library/core/src/clone.rs @@ -86,6 +86,46 @@ /// } /// ``` /// +/// If we `derive`: +/// +/// ``` +/// #[derive(Copy, Clone)] +/// struct Generate(fn() -> T); +/// ``` +/// +/// the auto-derived implementations will have unnecessary `T: Copy` and `T: Clone` bounds: +/// +/// ``` +/// # struct Generate(fn() -> T); +/// +/// // Automatically derived +/// impl Copy for Generate { } +/// +/// // Automatically derived +/// impl Clone for Generate { +/// fn clone(&self) -> Generate { +/// Generate(Clone::clone(&self.0)) +/// } +/// } +/// ``` +/// +/// The bounds are unnecessary because clearly the function itself should be +/// copy- and cloneable even if its return type is not: +/// +/// ```compile_fail,E0599 +/// #[derive(Copy, Clone)] +/// struct Generate(fn() -> T); +/// +/// struct NotCloneable; +/// +/// fn generate_not_cloneable() -> NotCloneable { +/// NotCloneable +/// } +/// +/// Generate(generate_not_cloneable).clone(); // error: trait bounds were not satisfied +/// // Note: With the manual implementations the above line will compile. +/// ``` +/// /// ## Additional implementors /// /// In addition to the [implementors listed below][impls], diff --git a/library/std/src/env.rs b/library/std/src/env.rs index d372fa64065f5..a2ac1b9052356 100644 --- a/library/std/src/env.rs +++ b/library/std/src/env.rs @@ -178,7 +178,8 @@ impl Iterator for Vars { #[stable(feature = "std_debug", since = "1.16.0")] impl fmt::Debug for Vars { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - f.debug_struct("Vars").finish_non_exhaustive() + let Self { inner: VarsOs { inner } } = self; + f.debug_struct("Vars").field("inner", inner).finish() } } @@ -196,7 +197,8 @@ impl Iterator for VarsOs { #[stable(feature = "std_debug", since = "1.16.0")] impl fmt::Debug for VarsOs { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - f.debug_struct("VarOs").finish_non_exhaustive() + let Self { inner } = self; + f.debug_struct("VarsOs").field("inner", inner).finish() } } @@ -829,7 +831,8 @@ impl DoubleEndedIterator for Args { #[stable(feature = "std_debug", since = "1.16.0")] impl fmt::Debug for Args { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - f.debug_struct("Args").field("inner", &self.inner.inner).finish() + let Self { inner: ArgsOs { inner } } = self; + f.debug_struct("Args").field("inner", inner).finish() } } @@ -870,7 +873,8 @@ impl DoubleEndedIterator for ArgsOs { #[stable(feature = "std_debug", since = "1.16.0")] impl fmt::Debug for ArgsOs { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - f.debug_struct("ArgsOs").field("inner", &self.inner).finish() + let Self { inner } = self; + f.debug_struct("ArgsOs").field("inner", inner).finish() } } diff --git a/library/std/src/env/tests.rs b/library/std/src/env/tests.rs index 94cace03af64e..558692295815d 100644 --- a/library/std/src/env/tests.rs +++ b/library/std/src/env/tests.rs @@ -95,8 +95,28 @@ fn args_debug() { format!("Args {{ inner: {:?} }}", args().collect::>()), format!("{:?}", args()) ); +} + +#[test] +fn args_os_debug() { assert_eq!( format!("ArgsOs {{ inner: {:?} }}", args_os().collect::>()), format!("{:?}", args_os()) ); } + +#[test] +fn vars_debug() { + assert_eq!( + format!("Vars {{ inner: {:?} }}", vars().collect::>()), + format!("{:?}", vars()) + ); +} + +#[test] +fn vars_os_debug() { + assert_eq!( + format!("VarsOs {{ inner: {:?} }}", vars_os().collect::>()), + format!("{:?}", vars_os()) + ); +} diff --git a/library/std/src/sys/hermit/os.rs b/library/std/src/sys/hermit/os.rs index e53dbae611981..a5ae26b9d33a5 100644 --- a/library/std/src/sys/hermit/os.rs +++ b/library/std/src/sys/hermit/os.rs @@ -112,6 +112,13 @@ pub struct Env { iter: vec::IntoIter<(OsString, OsString)>, } +impl fmt::Debug for Env { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + let Self { iter } = self; + f.debug_list().entries(iter.as_slice()).finish() + } +} + impl !Send for Env {} impl !Sync for Env {} diff --git a/library/std/src/sys/solid/os.rs b/library/std/src/sys/solid/os.rs index 6135921f0b5a8..a8e9464144422 100644 --- a/library/std/src/sys/solid/os.rs +++ b/library/std/src/sys/solid/os.rs @@ -85,6 +85,13 @@ pub struct Env { iter: vec::IntoIter<(OsString, OsString)>, } +impl fmt::Debug for Env { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + let Self { iter } = self; + f.debug_list().entries(iter.as_slice()).finish() + } +} + impl !Send for Env {} impl !Sync for Env {} diff --git a/library/std/src/sys/unix/os.rs b/library/std/src/sys/unix/os.rs index a68c14758ff79..79feda37e7b16 100644 --- a/library/std/src/sys/unix/os.rs +++ b/library/std/src/sys/unix/os.rs @@ -495,6 +495,13 @@ pub struct Env { iter: vec::IntoIter<(OsString, OsString)>, } +impl fmt::Debug for Env { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + let Self { iter } = self; + f.debug_list().entries(iter.as_slice()).finish() + } +} + impl !Send for Env {} impl !Sync for Env {} diff --git a/library/std/src/sys/unsupported/os.rs b/library/std/src/sys/unsupported/os.rs index e150ae143ad99..133a70be1e06b 100644 --- a/library/std/src/sys/unsupported/os.rs +++ b/library/std/src/sys/unsupported/os.rs @@ -65,10 +65,18 @@ pub fn current_exe() -> io::Result { pub struct Env(!); +impl fmt::Debug for Env { + fn fmt(&self, _: &mut fmt::Formatter<'_>) -> fmt::Result { + let Self(inner) = self; + match *inner {} + } +} + impl Iterator for Env { type Item = (OsString, OsString); fn next(&mut self) -> Option<(OsString, OsString)> { - self.0 + let Self(inner) = self; + match *inner {} } } diff --git a/library/std/src/sys/wasi/os.rs b/library/std/src/sys/wasi/os.rs index 197bdeda4fbe2..6aa3f05eaafad 100644 --- a/library/std/src/sys/wasi/os.rs +++ b/library/std/src/sys/wasi/os.rs @@ -142,10 +142,18 @@ impl StdError for JoinPathsError { pub fn current_exe() -> io::Result { unsupported() } + pub struct Env { iter: vec::IntoIter<(OsString, OsString)>, } +impl fmt::Debug for Env { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + let Self { iter } = self; + f.debug_list().entries(iter.as_slice()).finish() + } +} + impl !Send for Env {} impl !Sync for Env {} diff --git a/library/std/src/sys/windows/os.rs b/library/std/src/sys/windows/os.rs index d7adeb266ed93..ba0c05a81d482 100644 --- a/library/std/src/sys/windows/os.rs +++ b/library/std/src/sys/windows/os.rs @@ -85,25 +85,45 @@ pub fn error_string(mut errnum: i32) -> String { pub struct Env { base: c::LPWCH, - cur: c::LPWCH, + iter: EnvIterator, +} + +impl fmt::Debug for Env { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + let Self { base: _, iter } = self; + f.debug_list().entries(iter.clone()).finish() + } } impl Iterator for Env { type Item = (OsString, OsString); fn next(&mut self) -> Option<(OsString, OsString)> { + let Self { base: _, iter } = self; + iter.next() + } +} + +#[derive(Clone)] +struct EnvIterator(c::LPWCH); + +impl Iterator for EnvIterator { + type Item = (OsString, OsString); + + fn next(&mut self) -> Option<(OsString, OsString)> { + let Self(cur) = self; loop { unsafe { - if *self.cur == 0 { + if **cur == 0 { return None; } - let p = self.cur as *const u16; + let p = *cur as *const u16; let mut len = 0; while *p.add(len) != 0 { len += 1; } let s = slice::from_raw_parts(p, len); - self.cur = self.cur.add(len + 1); + *cur = cur.add(len + 1); // Windows allows environment variables to start with an equals // symbol (in any other position, this is the separator between @@ -137,7 +157,7 @@ pub fn env() -> Env { if ch.is_null() { panic!("failure getting env string from OS: {}", io::Error::last_os_error()); } - Env { base: ch, cur: ch } + Env { base: ch, iter: EnvIterator(ch) } } } diff --git a/src/tools/tidy/src/fluent_alphabetical.rs b/src/tools/tidy/src/fluent_alphabetical.rs index 5f8eaebf531fd..67b745373f019 100644 --- a/src/tools/tidy/src/fluent_alphabetical.rs +++ b/src/tools/tidy/src/fluent_alphabetical.rs @@ -23,7 +23,7 @@ fn check_alphabetic(filename: &str, fluent: &str, bad: &mut bool) { tidy_error!( bad, "{filename}: message `{}` appears before `{}`, but is alphabetically later than it -run tidy with `--bless` to sort the file correctly", +run `./x.py test tidy --bless` to sort the file correctly", name.as_str(), next.as_str() ); diff --git a/tests/ui/lint/missing-copy-implementations-negative-copy.rs b/tests/ui/lint/missing-copy-implementations-negative-copy.rs new file mode 100644 index 0000000000000..b29d2209fa9f9 --- /dev/null +++ b/tests/ui/lint/missing-copy-implementations-negative-copy.rs @@ -0,0 +1,15 @@ +// Regression test for issue #101980. +// Ensure that we don't suggest impl'ing `Copy` for a type if it already impl's `!Copy`. + +// check-pass + +#![feature(negative_impls)] +#![deny(missing_copy_implementations)] + +pub struct Struct { + pub field: i32, +} + +impl !Copy for Struct {} + +fn main() {}