diff options
3 files changed, 43 insertions, 1 deletions
diff --git a/src/librustc_ast_lowering/item.rs b/src/librustc_ast_lowering/item.rs index 5186e62fbf9..699f5c9778a 100644 --- a/src/librustc_ast_lowering/item.rs +++ b/src/librustc_ast_lowering/item.rs @@ -5,7 +5,7 @@ use crate::Arena; use rustc_ast::ast::*; use rustc_ast::node_id::NodeMap; use rustc_ast::ptr::P; -use rustc_ast::visit::{self, AssocCtxt, Visitor}; +use rustc_ast::visit::{self, AssocCtxt, FnCtxt, FnKind, Visitor}; use rustc_data_structures::fx::FxHashSet; use rustc_errors::struct_span_err; use rustc_hir as hir; @@ -75,6 +75,18 @@ impl<'a> Visitor<'a> for ItemLowerer<'a, '_, '_> { } } + fn visit_fn(&mut self, fk: FnKind<'a>, sp: Span, _: NodeId) { + match fk { + FnKind::Fn(FnCtxt::Foreign, _, sig, _, _) => { + self.visit_fn_header(&sig.header); + visit::walk_fn_decl(self, &sig.decl); + // Don't visit the foreign function body even if it has one, since lowering the + // body would have no meaning and will have already been caught as a parse error. + } + _ => visit::walk_fn(self, fk, sp), + } + } + fn visit_assoc_item(&mut self, item: &'a AssocItem, ctxt: AssocCtxt) { self.lctx.with_hir_id_owner(item.id, |lctx| match ctxt { AssocCtxt::Trait => { diff --git a/src/test/ui/foreign/issue-74120-lowering-of-ffi-block-bodies.rs b/src/test/ui/foreign/issue-74120-lowering-of-ffi-block-bodies.rs new file mode 100644 index 00000000000..a84065e0218 --- /dev/null +++ b/src/test/ui/foreign/issue-74120-lowering-of-ffi-block-bodies.rs @@ -0,0 +1,11 @@ +// Previously this ICE'd because `fn g()` would be lowered, but the block associated with `fn f()` +// wasn't. + +// compile-flags: --crate-type=lib + +extern "C" { + fn f() { + //~^ incorrect function inside `extern` block + fn g() {} + } +} diff --git a/src/test/ui/foreign/issue-74120-lowering-of-ffi-block-bodies.stderr b/src/test/ui/foreign/issue-74120-lowering-of-ffi-block-bodies.stderr new file mode 100644 index 00000000000..d4a9ca3e7c6 --- /dev/null +++ b/src/test/ui/foreign/issue-74120-lowering-of-ffi-block-bodies.stderr @@ -0,0 +1,19 @@ +error: incorrect function inside `extern` block + --> $DIR/issue-74120-lowering-of-ffi-block-bodies.rs:7:8 + | +LL | extern "C" { + | ---------- `extern` blocks define existing foreign functions and functions inside of them cannot have a body +LL | fn f() { + | ________^___- + | | | + | | cannot have a body +LL | | +LL | | fn g() {} +LL | | } + | |_____- help: remove the invalid body: `;` + | + = help: you might have meant to write a function accessible through FFI, which can be done by writing `extern fn` outside of the `extern` block + = note: for more information, visit https://doc.rust-lang.org/std/keyword.extern.html + +error: aborting due to previous error + |