diff --git a/src/librustc_mir/build/mod.rs b/src/librustc_mir/build/mod.rs index 19507c900da64..39c84b95f8f5d 100644 --- a/src/librustc_mir/build/mod.rs +++ b/src/librustc_mir/build/mod.rs @@ -581,6 +581,10 @@ fn should_abort_on_panic<'a, 'gcx, 'tcx>(tcx: TyCtxt<'a, 'gcx, 'tcx>, // Not callable from C, so we can safely unwind through these if abi == Abi::Rust || abi == Abi::RustCall { return false; } + // Validate `#[unwind]` syntax regardless of platform-specific panic strategy + let attrs = &tcx.get_attrs(fn_def_id); + let unwind_attr = attr::find_unwind_attr(Some(tcx.sess.diagnostic()), attrs); + // We never unwind, so it's not relevant to stop an unwind if tcx.sess.panic_strategy() != PanicStrategy::Unwind { return false; } @@ -589,8 +593,7 @@ fn should_abort_on_panic<'a, 'gcx, 'tcx>(tcx: TyCtxt<'a, 'gcx, 'tcx>, // This is a special case: some functions have a C abi but are meant to // unwind anyway. Don't stop them. - let attrs = &tcx.get_attrs(fn_def_id); - match attr::find_unwind_attr(Some(tcx.sess.diagnostic()), attrs) { + match unwind_attr { None => true, Some(UnwindAttr::Allowed) => false, Some(UnwindAttr::Aborts) => true, diff --git a/src/libsyntax/attr/builtin.rs b/src/libsyntax/attr/builtin.rs index e84adc01cf04a..f7a000935caf0 100644 --- a/src/libsyntax/attr/builtin.rs +++ b/src/libsyntax/attr/builtin.rs @@ -7,7 +7,7 @@ use crate::parse::ParseSess; use errors::{Applicability, Handler}; use syntax_pos::{symbol::Symbol, Span}; -use super::{list_contains_name, mark_used, MetaItemKind}; +use super::{mark_used, MetaItemKind}; enum AttrError { MultipleItem(Name), @@ -79,40 +79,26 @@ pub enum UnwindAttr { /// Determine what `#[unwind]` attribute is present in `attrs`, if any. pub fn find_unwind_attr(diagnostic: Option<&Handler>, attrs: &[Attribute]) -> Option { - let syntax_error = |attr: &Attribute| { - mark_used(attr); - diagnostic.map(|d| { - span_err!(d, attr.span, E0633, "malformed `#[unwind]` attribute"); - }); - None - }; - attrs.iter().fold(None, |ia, attr| { - if attr.path != "unwind" { - return ia; - } - let meta = match attr.meta() { - Some(meta) => meta.node, - None => return ia, - }; - match meta { - MetaItemKind::Word => { - syntax_error(attr) - } - MetaItemKind::List(ref items) => { - mark_used(attr); - if items.len() != 1 { - syntax_error(attr) - } else if list_contains_name(&items[..], "allowed") { - Some(UnwindAttr::Allowed) - } else if list_contains_name(&items[..], "aborts") { - Some(UnwindAttr::Aborts) - } else { - syntax_error(attr) + if attr.check_name("unwind") { + if let Some(meta) = attr.meta() { + if let MetaItemKind::List(items) = meta.node { + if items.len() == 1 { + if items[0].check_name("allowed") { + return Some(UnwindAttr::Allowed); + } else if items[0].check_name("aborts") { + return Some(UnwindAttr::Aborts); + } + } + + diagnostic.map(|d| { + span_err!(d, attr.span, E0633, "malformed `#[unwind]` attribute"); + }); } } - _ => ia, } + + ia }) } diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs index cc1953e69d4ca..93c6de274eeea 100644 --- a/src/libsyntax/feature_gate.rs +++ b/src/libsyntax/feature_gate.rs @@ -1173,7 +1173,7 @@ pub const BUILTIN_ATTRIBUTES: &[(&str, AttributeType, AttributeTemplate, Attribu "dropck_eyepatch", "may_dangle has unstable semantics and may be removed in the future", cfg_fn!(dropck_eyepatch))), - ("unwind", Whitelisted, template!(List: "allowed"), Gated(Stability::Unstable, + ("unwind", Whitelisted, template!(List: "allowed|aborts"), Gated(Stability::Unstable, "unwind_attributes", "#[unwind] is experimental", cfg_fn!(unwind_attributes))), diff --git a/src/test/ui/malformed/malformed-unwind-1.rs b/src/test/ui/malformed/malformed-unwind-1.rs new file mode 100644 index 0000000000000..e34c288c027c2 --- /dev/null +++ b/src/test/ui/malformed/malformed-unwind-1.rs @@ -0,0 +1,11 @@ +#![feature(unwind_attributes)] + +#[unwind] +//~^ ERROR attribute must be of the form +extern "C" fn f1() {} + +#[unwind = ""] +//~^ ERROR attribute must be of the form +extern "C" fn f2() {} + +fn main() {} diff --git a/src/test/ui/malformed/malformed-unwind-1.stderr b/src/test/ui/malformed/malformed-unwind-1.stderr new file mode 100644 index 0000000000000..852136eed91bd --- /dev/null +++ b/src/test/ui/malformed/malformed-unwind-1.stderr @@ -0,0 +1,14 @@ +error: attribute must be of the form `#[unwind(allowed|aborts)]` + --> $DIR/malformed-unwind-1.rs:3:1 + | +LL | #[unwind] + | ^^^^^^^^^ + +error: attribute must be of the form `#[unwind(allowed|aborts)]` + --> $DIR/malformed-unwind-1.rs:7:1 + | +LL | #[unwind = ""] + | ^^^^^^^^^^^^^^ + +error: aborting due to 2 previous errors + diff --git a/src/test/ui/malformed/malformed-unwind-2.rs b/src/test/ui/malformed/malformed-unwind-2.rs new file mode 100644 index 0000000000000..d4955b4330930 --- /dev/null +++ b/src/test/ui/malformed/malformed-unwind-2.rs @@ -0,0 +1,11 @@ +#![feature(unwind_attributes)] + +#[unwind(allowed, aborts)] +//~^ ERROR malformed `#[unwind]` attribute +extern "C" fn f1() {} + +#[unwind(unsupported)] +//~^ ERROR malformed `#[unwind]` attribute +extern "C" fn f2() {} + +fn main() {} diff --git a/src/test/ui/malformed/malformed-unwind-2.stderr b/src/test/ui/malformed/malformed-unwind-2.stderr new file mode 100644 index 0000000000000..88fc4e00a2fd3 --- /dev/null +++ b/src/test/ui/malformed/malformed-unwind-2.stderr @@ -0,0 +1,15 @@ +error[E0633]: malformed `#[unwind]` attribute + --> $DIR/malformed-unwind-2.rs:3:1 + | +LL | #[unwind(allowed, aborts)] + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error[E0633]: malformed `#[unwind]` attribute + --> $DIR/malformed-unwind-2.rs:7:1 + | +LL | #[unwind(unsupported)] + | ^^^^^^^^^^^^^^^^^^^^^^ + +error: aborting due to 2 previous errors + +For more information about this error, try `rustc --explain E0633`.