[gcc r16-3008] gccrs: Recognize rustc_args_required_const attribute

[Arthur Cohen via Gcc-cvs]

https://gcc.gnu.org/g:95c619976ff94dff1b84a5cff7e65a640d667996

commit r16-3008-g95c619976ff94dff1b84a5cff7e65a640d667996
Author: Owen Avery <powerboat9.ga...@gmail.com>
Date:   Fri Jul 11 22:47:01 2025 -0400

    gccrs: Recognize rustc_args_required_const attribute
    
    This doesn't handle rustc_args_required_const, but it does allow us to
    recognize it as a valid attribute.
    
    gcc/rust/ChangeLog:
    
            * util/rust-attribute-values.h
            (Attributes::RUSTC_ARGS_REQUIRED_CONST): New constexpr variable.
            * util/rust-attributes.cc (__definitions): New entry for
            RUSTC_ARGS_REQUIRED_CONST.
    
    Signed-off-by: Owen Avery <powerboat9.ga...@gmail.com>

Diff:
---
 gcc/rust/util/rust-attribute-values.h | 3 +++
 gcc/rust/util/rust-attributes.cc      | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/gcc/rust/util/rust-attribute-values.h 
b/gcc/rust/util/rust-attribute-values.h
index 09ef56647953..367044a36c1c 100644
--- a/gcc/rust/util/rust-attribute-values.h
+++ b/gcc/rust/util/rust-attribute-values.h
@@ -89,6 +89,9 @@ public:
   static constexpr auto &TEST = "test";
 
   static constexpr auto &SIMD_TEST = "simd_test";
+
+  static constexpr auto &RUSTC_ARGS_REQUIRED_CONST
+    = "rustc_args_required_const";
 };
 } // namespace Values
 } // namespace Rust
diff --git a/gcc/rust/util/rust-attributes.cc b/gcc/rust/util/rust-attributes.cc
index 273e25c43d30..c846c2d5c33c 100644
--- a/gcc/rust/util/rust-attributes.cc
+++ b/gcc/rust/util/rust-attributes.cc
@@ -88,6 +88,9 @@ static const BuiltinAttrDefinition __definitions[]
 
      {Attrs::RUSTC_LAYOUT_SCALAR_VALID_RANGE_START, CODE_GENERATION},
 
+     // TODO: be careful about calling functions marked with this?
+     {Attrs::RUSTC_ARGS_REQUIRED_CONST, CODE_GENERATION},
+
      {Attrs::PRELUDE_IMPORT, NAME_RESOLUTION},
 
      {Attrs::RUSTC_DIAGNOSTIC_ITEM, STATIC_ANALYSIS},