From: Arthur Cohen <arthur.co...@embecosm.com>
gcc/rust/ChangeLog:
* expand/rust-macro-expand.cc (MacroExpander::expand_decl_macro): Call
into
TokenTreeDesugar.
* expand/rust-token-tree-desugar.cc: New file.
* expand/rust-token-tree-desugar.h: New file.
* Make-lang.in: Compile them.
gcc/testsuite/ChangeLog:
* rust/compile/macros/mbe/macro-issue3709-1.rs: New test.
* rust/compile/macros/mbe/macro-issue3709-2.rs: New test.
---
gcc/rust/Make-lang.in | 1 +
gcc/rust/expand/rust-macro-expand.cc | 6 +-
gcc/rust/expand/rust-token-tree-desugar.cc | 72 +++++++++++++++++
gcc/rust/expand/rust-token-tree-desugar.h | 55 +++++++++++++
.../compile/macros/mbe/macro-issue3693.rs | 10 +++
.../compile/macros/mbe/macro-issue3709-1.rs | 10 +++
.../compile/macros/mbe/macro-issue3709-2.rs | 81 +++++++++++++++++++
7 files changed, 234 insertions(+), 1 deletion(-)
create mode 100644 gcc/rust/expand/rust-token-tree-desugar.cc
create mode 100644 gcc/rust/expand/rust-token-tree-desugar.h
create mode 100644 gcc/testsuite/rust/compile/macros/mbe/macro-issue3693.rs
create mode 100644 gcc/testsuite/rust/compile/macros/mbe/macro-issue3709-1.rs
create mode 100644 gcc/testsuite/rust/compile/macros/mbe/macro-issue3709-2.rs
diff --git a/gcc/rust/Make-lang.in b/gcc/rust/Make-lang.in
index 4028b47fa87..835e113aee2 100644
--- a/gcc/rust/Make-lang.in
+++ b/gcc/rust/Make-lang.in
@@ -115,6 +115,7 @@ GRS_OBJS = \
rust/rust-macro-builtins-format-args.o \
rust/rust-macro-builtins-location.o \
rust/rust-macro-builtins-include.o \
+ rust/rust-token-tree-desugar.o \
rust/rust-fmt.o \
rust/rust-hir.o \
rust/rust-hir-map.o \
diff --git a/gcc/rust/expand/rust-macro-expand.cc
b/gcc/rust/expand/rust-macro-expand.cc
index 6e62a083ae7..673b8fb20fa 100644
--- a/gcc/rust/expand/rust-macro-expand.cc
+++ b/gcc/rust/expand/rust-macro-expand.cc
@@ -28,6 +28,7 @@
#include "rust-cfg-strip.h"
#include "rust-early-name-resolver.h"
#include "rust-proc-macro.h"
+#include "rust-token-tree-desugar.h"
namespace Rust {
@@ -78,7 +79,10 @@ MacroExpander::expand_decl_macro (location_t invoc_locus,
* trees.
*/
- AST::DelimTokenTree &invoc_token_tree = invoc.get_delim_tok_tree ();
+ AST::DelimTokenTree &invoc_token_tree_sugar = invoc.get_delim_tok_tree ();
+
+ // We must first desugar doc comments into proper attributes
+ auto invoc_token_tree = AST::TokenTreeDesugar ().go (invoc_token_tree_sugar);
// find matching arm
AST::MacroRule *matched_rule = nullptr;
diff --git a/gcc/rust/expand/rust-token-tree-desugar.cc
b/gcc/rust/expand/rust-token-tree-desugar.cc
new file mode 100644
index 00000000000..3b471805924
--- /dev/null
+++ b/gcc/rust/expand/rust-token-tree-desugar.cc
@@ -0,0 +1,72 @@
+// Copyright (C) 2025 Free Software Foundation, Inc.
+
+// This file is part of GCC.
+
+// GCC is free software; you can redistribute it and/or modify it under
+// the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3, or (at your option) any later
+// version.
+
+// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+// for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with GCC; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+#include "rust-token-tree-desugar.h"
+#include "rust-ast.h"
+#include "rust-token.h"
+
+namespace Rust {
+namespace AST {
+
+DelimTokenTree
+TokenTreeDesugar::go (DelimTokenTree &tts)
+{
+ tts.accept_vis (*this);
+
+ return DelimTokenTree (tts.get_delim_type (), std::move (desugared),
+ tts.get_locus ());
+}
+
+void
+TokenTreeDesugar::append (TokenPtr &&new_token)
+{
+ desugared.emplace_back (std::make_unique<Token> (std::move (new_token)));
+}
+
+void
+TokenTreeDesugar::append (std::unique_ptr<TokenTree> &&new_token)
+{
+ desugared.emplace_back (std::move (new_token));
+}
+
+void
+TokenTreeDesugar::visit (Token &tts)
+{
+ if (tts.get_id () == TokenId::OUTER_DOC_COMMENT
+ || tts.get_id () == TokenId::INNER_DOC_COMMENT)
+ {
+ append (Rust::Token::make (TokenId::HASH, tts.get_locus ()));
+
+ if (tts.get_id () == TokenId::INNER_DOC_COMMENT)
+ append (Rust::Token::make (EXCLAM, tts.get_locus ()));
+
+ append (Rust::Token::make (TokenId::LEFT_SQUARE, tts.get_locus ()));
+ append (Rust::Token::make_identifier (tts.get_locus (), "doc"));
+ append (Rust::Token::make (TokenId::EQUAL, tts.get_locus ()));
+ append (Rust::Token::make_string (tts.get_locus (),
+ std::string (tts.get_str ())));
+ append (Rust::Token::make (TokenId::RIGHT_SQUARE, tts.get_locus ()));
+ }
+ else
+ {
+ append (tts.clone_token ());
+ }
+}
+
+}; // namespace AST
+}; // namespace Rust
diff --git a/gcc/rust/expand/rust-token-tree-desugar.h
b/gcc/rust/expand/rust-token-tree-desugar.h
new file mode 100644
index 00000000000..ccba53b1102
--- /dev/null
+++ b/gcc/rust/expand/rust-token-tree-desugar.h
@@ -0,0 +1,55 @@
+// Copyright (C) 2025 Free Software Foundation, Inc.
+
+// This file is part of GCC.
+
+// GCC is free software; you can redistribute it and/or modify it under
+// the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3, or (at your option) any later
+// version.
+
+// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+// for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with GCC; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+#ifndef RUST_TOKEN_TREE_DESUGAR_H
+#define RUST_TOKEN_TREE_DESUGAR_H
+
+#include "rust-ast-visitor.h"
+#include "rust-system.h"
+#include "rust-ast.h"
+
+namespace Rust {
+namespace AST {
+
+/**
+ * Desugar a given token-tree before parsing it for a macro invocation. At the
+ * moment, the sole purpose of this desugar is to transform doc-comments into
+ * their attribute form (/// comment -> #[doc = "comment"])
+ */
+class TokenTreeDesugar : public DefaultASTVisitor
+{
+public:
+ TokenTreeDesugar () : desugared (std::vector<std::unique_ptr<TokenTree>> ())
+ {}
+
+ DelimTokenTree go (DelimTokenTree &tts);
+
+private:
+ std::vector<std::unique_ptr<TokenTree>> desugared;
+ void append (TokenPtr &&new_token);
+ void append (std::unique_ptr<TokenTree> &&new_token);
+
+ using DefaultASTVisitor::visit;
+
+ virtual void visit (Token &tts) override;
+};
+
+}; // namespace AST
+}; // namespace Rust
+
+#endif //! RUST_TOKEN_TREE_DESUGAR_H
diff --git a/gcc/testsuite/rust/compile/macros/mbe/macro-issue3693.rs
b/gcc/testsuite/rust/compile/macros/mbe/macro-issue3693.rs
new file mode 100644
index 00000000000..e990c8bc355
--- /dev/null
+++ b/gcc/testsuite/rust/compile/macros/mbe/macro-issue3693.rs
@@ -0,0 +1,10 @@
+macro_rules! generate_pattern_iterators {
+ {
+ $(#[$forward_iterator_attribute:meta])*
+ } => {
+ }
+}
+
+generate_pattern_iterators! {
+ /// Created with the method [`split`].
+}
diff --git a/gcc/testsuite/rust/compile/macros/mbe/macro-issue3709-1.rs
b/gcc/testsuite/rust/compile/macros/mbe/macro-issue3709-1.rs
new file mode 100644
index 00000000000..6fc3a319dd4
--- /dev/null
+++ b/gcc/testsuite/rust/compile/macros/mbe/macro-issue3709-1.rs
@@ -0,0 +1,10 @@
+macro_rules! doc_comment {
+ (#[ $attr: meta ]) => {
+ #[$attr]
+ struct Generated; // { dg-warning "never constructed" }
+ };
+}
+
+doc_comment! {
+ /// This is a generated struct
+}
diff --git a/gcc/testsuite/rust/compile/macros/mbe/macro-issue3709-2.rs
b/gcc/testsuite/rust/compile/macros/mbe/macro-issue3709-2.rs
new file mode 100644
index 00000000000..cfc8ab460b7
--- /dev/null
+++ b/gcc/testsuite/rust/compile/macros/mbe/macro-issue3709-2.rs
@@ -0,0 +1,81 @@
+// { dg-additional-options "-frust-name-resolution-2.0
-frust-compile-until=lowering" }
+
+macro_rules! impl_fn_for_zst {
+ ($(
+ $( #[$attr: meta] )*
+ struct $Name: ident impl$( <$( $lifetime : lifetime ),+> )? Fn =
+ |$( $arg: ident: $ArgTy: ty ),*| -> $ReturnTy: ty
+ $body: block;
+ )+) => {
+ $(
+ $( #[$attr] )*
+ struct $Name;
+
+ impl $( <$( $lifetime ),+> )? Fn<($( $ArgTy, )*)> for $Name {
+ #[inline]
+ extern "rust-call" fn call(&self, ($( $arg, )*): ($( $ArgTy,
)*)) -> $ReturnTy {
+ $body
+ }
+ }
+
+ impl $( <$( $lifetime ),+> )? FnMut<($( $ArgTy, )*)> for $Name {
+ #[inline]
+ extern "rust-call" fn call_mut(
+ &mut self,
+ ($( $arg, )*): ($( $ArgTy, )*)
+ ) -> $ReturnTy {
+ Fn::call(&*self, ($( $arg, )*))
+ }
+ }
+
+ impl $( <$( $lifetime ),+> )? FnOnce<($( $ArgTy, )*)> for $Name {
+ type Output = $ReturnTy;
+
+ #[inline]
+ extern "rust-call" fn call_once(self, ($( $arg, )*): ($(
$ArgTy, )*)) -> $ReturnTy {
+ Fn::call(&self, ($( $arg, )*))
+ }
+ }
+ )+
+ }
+}
+
+#[lang = "sized"]
+trait Sized {}
+
+#[lang = "copy"]
+trait Copy {}
+
+#[lang = "fn"]
+pub trait Fn<Args>: FnMut<Args> {
+ /// Performs the call operation.
+ #[unstable(feature = "fn_traits", issue = "29625")]
+ extern "rust-call" fn call(&self, args: Args) -> Self::Output;
+}
+
+#[lang = "fn_mut"]
+#[must_use = "closures are lazy and do nothing unless called"]
+pub trait FnMut<Args>: FnOnce<Args> {
+ /// Performs the call operation.
+ #[unstable(feature = "fn_traits", issue = "29625")]
+ extern "rust-call" fn call_mut(&mut self, args: Args) -> Self::Output;
+}
+
+#[lang = "fn_once"]
+pub trait FnOnce<Args> {
+ /// The returned type after the call operator is used.
+ #[lang = "fn_once_output"]
+ #[stable(feature = "fn_once_output", since = "1.12.0")]
+ type Output;
+
+ /// Performs the call operation.
+ #[unstable(feature = "fn_traits", issue = "29625")]
+ extern "rust-call" fn call_once(self, args: Args) -> Self::Output;
+}
+
+impl_fn_for_zst! {
+ /// Documentation for the zst
+ #[derive(Copy)]
+ struct LinesAnyMap impl<'a> Fn = |line: &'a str| -> () {
+ };
+}
--
2.49.0
