diff --git a/compiler/rustc_parse/messages.ftl b/compiler/rustc_parse/messages.ftl index 3a4c9348b327..f83cf645f829 100644 --- a/compiler/rustc_parse/messages.ftl +++ b/compiler/rustc_parse/messages.ftl @@ -191,6 +191,9 @@ parse_dotdotdot_rest_pattern = unexpected `...` .suggestion = for a rest pattern, use `..` instead of `...` .note = only `extern "C"` and `extern "C-unwind"` functions may have a C variable argument list +parse_dotdotdot_rest_type = unexpected `...` + .note = only `extern "C"` and `extern "C-unwind"` functions may have a C variable argument list + parse_double_colon_in_bound = expected `:` followed by trait or lifetime .suggestion = use single colon diff --git a/compiler/rustc_parse/src/errors.rs b/compiler/rustc_parse/src/errors.rs index 2b107fe35d59..1abeee6fe433 100644 --- a/compiler/rustc_parse/src/errors.rs +++ b/compiler/rustc_parse/src/errors.rs @@ -3032,6 +3032,14 @@ pub(crate) struct NestedCVariadicType { pub span: Span, } +#[derive(Diagnostic)] +#[diag(parse_dotdotdot_rest_type)] +#[note] +pub(crate) struct InvalidCVariadicType { + #[primary_span] + pub span: Span, +} + #[derive(Diagnostic)] #[diag(parse_invalid_dyn_keyword)] #[help] diff --git a/compiler/rustc_parse/src/parser/ty.rs b/compiler/rustc_parse/src/parser/ty.rs index 23aaafac934e..65347496599d 100644 --- a/compiler/rustc_parse/src/parser/ty.rs +++ b/compiler/rustc_parse/src/parser/ty.rs @@ -15,8 +15,8 @@ use crate::errors::{ self, AttributeOnEmptyType, AttributeOnType, DynAfterMut, ExpectedFnPathFoundFnKeyword, ExpectedMutOrConstInRawPointerType, FnPtrWithGenerics, FnPtrWithGenericsSugg, - HelpUseLatestEdition, InvalidDynKeyword, LifetimeAfterMut, NeedPlusAfterTraitObjectLifetime, - NestedCVariadicType, ReturnTypesUseThinArrow, + HelpUseLatestEdition, InvalidCVariadicType, InvalidDynKeyword, LifetimeAfterMut, + NeedPlusAfterTraitObjectLifetime, NestedCVariadicType, ReturnTypesUseThinArrow, }; use crate::parser::item::FrontMatterParsingMode; use crate::parser::{FnContext, FnParseMode}; @@ -106,6 +106,15 @@ fn can_begin_dyn_bound_in_edition_2015(t: &Token) -> bool { impl<'a> Parser<'a> { /// Parses a type. pub fn parse_ty(&mut self) -> PResult<'a, Box> { + if self.token == token::DotDotDot { + // We special case this so that we don't talk about "nested C-variadics" in types. + // We still pass in `AllowCVariadic::No` so that `parse_ty_common` can complain about + // things like `Vec<...>`. + let span = self.token.span; + self.bump(); + let kind = TyKind::Err(self.dcx().emit_err(InvalidCVariadicType { span })); + return Ok(self.mk_ty(span, kind)); + } // Make sure deeply nested types don't overflow the stack. ensure_sufficient_stack(|| { self.parse_ty_common( diff --git a/tests/ui/c-variadic/no-closure.rs b/tests/ui/c-variadic/no-closure.rs index a5b791fbca80..830ed962a8c4 100644 --- a/tests/ui/c-variadic/no-closure.rs +++ b/tests/ui/c-variadic/no-closure.rs @@ -4,13 +4,17 @@ // Check that `...` in closures is rejected. const F: extern "C" fn(...) = |_: ...| {}; -//~^ ERROR C-variadic type `...` may not be nested inside another type +//~^ ERROR: unexpected `...` +//~| NOTE: only `extern "C"` and `extern "C-unwind"` functions may have a C variable argument list fn foo() { let f = |...| {}; //~^ ERROR: unexpected `...` + //~| NOTE: not a valid pattern + //~| NOTE: only `extern "C"` and `extern "C-unwind"` functions may have a C variable argument list let f = |_: ...| {}; - //~^ ERROR C-variadic type `...` may not be nested inside another type + //~^ ERROR: unexpected `...` + //~| NOTE: only `extern "C"` and `extern "C-unwind"` functions may have a C variable argument list f(1i64) } diff --git a/tests/ui/c-variadic/no-closure.stderr b/tests/ui/c-variadic/no-closure.stderr index 4b553c215979..0946c4632e6e 100644 --- a/tests/ui/c-variadic/no-closure.stderr +++ b/tests/ui/c-variadic/no-closure.stderr @@ -1,23 +1,26 @@ -error[E0743]: C-variadic type `...` may not be nested inside another type +error: unexpected `...` --> $DIR/no-closure.rs:6:35 | LL | const F: extern "C" fn(...) = |_: ...| {}; | ^^^ + | + = note: only `extern "C"` and `extern "C-unwind"` functions may have a C variable argument list error: unexpected `...` - --> $DIR/no-closure.rs:10:14 + --> $DIR/no-closure.rs:11:14 | LL | let f = |...| {}; | ^^^ not a valid pattern | = note: only `extern "C"` and `extern "C-unwind"` functions may have a C variable argument list -error[E0743]: C-variadic type `...` may not be nested inside another type - --> $DIR/no-closure.rs:13:17 +error: unexpected `...` + --> $DIR/no-closure.rs:16:17 | LL | let f = |_: ...| {}; | ^^^ + | + = note: only `extern "C"` and `extern "C-unwind"` functions may have a C variable argument list error: aborting due to 3 previous errors -For more information about this error, try `rustc --explain E0743`.