https://gcc.gnu.org/g:41cd035570ec2767d23647a7764c24d6c1a7a82e
commit r15-8629-g41cd035570ec2767d23647a7764c24d6c1a7a82e
Author: Arthur Cohen <arthur.co...@embecosm.com>
Date: Thu Dec 26 10:50:13 2024 +0000
gccrs: derive(Clone): Manually generate AssertParamIsCopy struct for unions
gcc/rust/ChangeLog:
* expand/rust-derive-clone.cc (DeriveClone::visit_union): Manually
generate
the struct used for asserting a union implements Copy.
Diff:
---
gcc/rust/expand/rust-derive-clone.cc | 38 ++++++++++++++++++++++++++++++++----
1 file changed, 34 insertions(+), 4 deletions(-)
diff --git a/gcc/rust/expand/rust-derive-clone.cc
b/gcc/rust/expand/rust-derive-clone.cc
index 18436be4bf75..8093bf67ff0a 100644
--- a/gcc/rust/expand/rust-derive-clone.cc
+++ b/gcc/rust/expand/rust-derive-clone.cc
@@ -17,6 +17,8 @@
// <http://www.gnu.org/licenses/>.
#include "rust-derive-clone.h"
+#include "rust-ast.h"
+#include "rust-ast-dump.h"
#include "rust-item.h"
namespace Rust {
@@ -238,13 +240,40 @@ void
DeriveClone::visit_union (Union &item)
{
// FIXME: Should be $crate::core::clone::AssertParamIsCopy (or similar)
+ // (Rust-GCC#3329)
+
+ auto copy_path = TypePath (vec (builder.type_path_segment ("Copy")), loc);
+ auto sized_path = TypePath (vec (builder.type_path_segment ("Sized")), loc);
+
+ auto copy_bound = std::unique_ptr<TypeParamBound> (
+ new TraitBound (copy_path, item.get_locus ()));
+ auto sized_bound = std::unique_ptr<TypeParamBound> (
+ new TraitBound (sized_path, item.get_locus (), false, true));
+
+ auto bounds = std::vector<std::unique_ptr<TypeParamBound>> ();
+ bounds.emplace_back (std::move (copy_bound));
+ bounds.emplace_back (std::move (sized_bound));
+
+ // struct AssertParamIsCopy<T: Copy + ?Sized> { _t: PhantomData<T> }
+ auto assert_param_is_copy = "AssertParamIsCopy";
+ auto t = std::unique_ptr<GenericParam> (
+ new TypeParam (Identifier ("T"), item.get_locus (), std::move (bounds)));
+ auto assert_param_is_copy_struct = builder.struct_struct (
+ assert_param_is_copy, vec (std::move (t)),
+ {StructField (
+ Identifier ("_t"),
+ builder.single_generic_type_path (
+ "PhantomData",
+ GenericArgs (
+ {}, {GenericArg::create_type (builder.single_type_path ("T"))}, {})),
+ Visibility::create_private (), item.get_locus ())});
// <Self>
auto arg = GenericArg::create_type (builder.single_type_path ("Self"));
// AssertParamIsCopy::<Self>
auto type = std::unique_ptr<TypePathSegment> (
- new TypePathSegmentGeneric (PathIdentSegment ("AssertParamIsCopy", loc),
+ new TypePathSegmentGeneric (PathIdentSegment (assert_param_is_copy, loc),
false, GenericArgs ({}, {arg}, {}, loc), loc));
auto type_paths = std::vector<std::unique_ptr<TypePathSegment>> ();
type_paths.emplace_back (std::move (type));
@@ -252,11 +281,12 @@ DeriveClone::visit_union (Union &item)
auto full_path
= std::unique_ptr<Type> (new TypePath ({std::move (type_paths)}, loc));
- auto stmts = std::vector<std::unique_ptr<Stmt>> ();
- stmts.emplace_back (
- builder.let (builder.wildcard (), std::move (full_path), nullptr));
auto tail_expr = builder.deref (builder.identifier ("self"));
+ auto stmts
+ = vec (std::move (assert_param_is_copy_struct),
+ builder.let (builder.wildcard (), std::move (full_path), nullptr));
+
auto block = builder.block (std::move (stmts), std::move (tail_expr));
expanded = clone_impl (clone_fn (std::move (block)),
