https://gcc.gnu.org/g:2c109a2e8a97980b293edb7dc3609556473c7f3d
commit 2c109a2e8a97980b293edb7dc3609556473c7f3d
Author: Zhi Heng <yapz...@gmail.com>
Date: Thu Apr 3 20:23:46 2025 +0800
gccrs: Implement typecheck for zero-variant enums
gcc/rust/ChangeLog:
* typecheck/rust-tyty.h: Add new `ReprKind` enum to
`ReprOptions`.
* typecheck/rust-hir-type-check-base.cc: Handle setting of
`repr_kind`.
* typecheck/rust-hir-type-check-item.cc: New check for
zero-variant enums.
Signed-off-by: Yap Zhi Heng <yapz...@gmail.com>
Diff:
---
gcc/rust/typecheck/rust-hir-type-check-base.cc | 34 +++++++++++++++++++++++---
gcc/rust/typecheck/rust-hir-type-check-item.cc | 12 +++++++++
gcc/rust/typecheck/rust-tyty.h | 17 ++++++++++---
gcc/testsuite/rust/compile/issue-3530-1.rs | 2 ++
gcc/testsuite/rust/compile/issue-3530-2.rs | 2 ++
5 files changed, 61 insertions(+), 6 deletions(-)
diff --git a/gcc/rust/typecheck/rust-hir-type-check-base.cc
b/gcc/rust/typecheck/rust-hir-type-check-base.cc
index f2310216424c..f066ddc4fd31 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-base.cc
+++ b/gcc/rust/typecheck/rust-hir-type-check-base.cc
@@ -353,13 +353,27 @@ TypeCheckBase::parse_repr_options (const AST::AttrVec
&attrs, location_t locus)
// manually parsing the string "packed(2)" here.
size_t oparen = inline_option.find ('(', 0);
- bool is_pack = false, is_align = false;
+ bool is_pack = false, is_align = false, is_c = false,
+ is_integer = false;
unsigned char value = 1;
if (oparen == std::string::npos)
{
is_pack = inline_option.compare ("packed") == 0;
is_align = inline_option.compare ("align") == 0;
+ is_c = inline_option.compare ("C") == 0;
+ is_integer = (inline_option.compare ("isize") == 0
+ || inline_option.compare ("i8") == 0
+ || inline_option.compare ("i16") == 0
+ || inline_option.compare ("i32") == 0
+ || inline_option.compare ("i64") == 0
+ || inline_option.compare ("i128") == 0
+ || inline_option.compare ("usize") == 0
+ || inline_option.compare ("u8") == 0
+ || inline_option.compare ("u16") == 0
+ || inline_option.compare ("u32") == 0
+ || inline_option.compare ("u64") == 0
+ || inline_option.compare ("u128") == 0);
}
else
@@ -379,9 +393,23 @@ TypeCheckBase::parse_repr_options (const AST::AttrVec
&attrs, location_t locus)
}
if (is_pack)
- repr.pack = value;
+ {
+ repr.repr_kind = TyTy::ADTType::ReprKind::PACKED;
+ repr.pack = value;
+ }
else if (is_align)
- repr.align = value;
+ {
+ repr.repr_kind = TyTy::ADTType::ReprKind::ALIGN;
+ repr.align = value;
+ }
+ else if (is_c)
+ {
+ repr.repr_kind = TyTy::ADTType::ReprKind::C;
+ }
+ else if (is_integer)
+ {
+ repr.repr_kind = TyTy::ADTType::ReprKind::INT;
+ }
delete meta_items;
diff --git a/gcc/rust/typecheck/rust-hir-type-check-item.cc
b/gcc/rust/typecheck/rust-hir-type-check-item.cc
index f13e3a960d98..7491cb47f5a7 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-item.cc
+++ b/gcc/rust/typecheck/rust-hir-type-check-item.cc
@@ -355,6 +355,18 @@ TypeCheckItem::visit (HIR::Enum &enum_decl)
variants.push_back (field_type);
}
+ // Check for zero-variant enum compatibility before processing repr attribute
+ if (enum_decl.is_zero_variant ())
+ {
+ if (repr.repr_kind == TyTy::ADTType::ReprKind::INT
+ || repr.repr_kind == TyTy::ADTType::ReprKind::C)
+ {
+ rust_error_at (enum_decl.get_locus (),
+ "unsupported representation for zero-variant enum");
+ return;
+ }
+ }
+
// get the path
tl::optional<CanonicalPath> canonical_path;
diff --git a/gcc/rust/typecheck/rust-tyty.h b/gcc/rust/typecheck/rust-tyty.h
index dc30d7dd0686..cd7bf24585ee 100644
--- a/gcc/rust/typecheck/rust-tyty.h
+++ b/gcc/rust/typecheck/rust-tyty.h
@@ -711,12 +711,23 @@ public:
ENUM
};
+ enum ReprKind
+ {
+ RUST,
+ C,
+ INT,
+ ALIGN,
+ PACKED,
+ // TRANSPARENT,
+ // PACKED,
+ // SIMD,
+ // ...
+ };
+
// Representation options, specified via attributes e.g. #[repr(packed)]
struct ReprOptions
{
- // bool is_c;
- // bool is_transparent;
- //...
+ ReprKind repr_kind = ReprKind::RUST;
// For align and pack: 0 = unspecified. Nonzero = byte alignment.
// It is an error for both to be nonzero, this should be caught when
diff --git a/gcc/testsuite/rust/compile/issue-3530-1.rs
b/gcc/testsuite/rust/compile/issue-3530-1.rs
new file mode 100644
index 000000000000..b38b5cd1f3f2
--- /dev/null
+++ b/gcc/testsuite/rust/compile/issue-3530-1.rs
@@ -0,0 +1,2 @@
+#[repr(i32)]
+enum NightsWatch {} // { dg-error "unsupported representation for zero-variant
enum" }
diff --git a/gcc/testsuite/rust/compile/issue-3530-2.rs
b/gcc/testsuite/rust/compile/issue-3530-2.rs
new file mode 100644
index 000000000000..74327307141f
--- /dev/null
+++ b/gcc/testsuite/rust/compile/issue-3530-2.rs
@@ -0,0 +1,2 @@
+#[repr(C)]
+enum NightsWatch {} // { dg-error "unsupported representation for zero-variant
enum" }
