[gcc r15-2585] gccrs: Recognize unstable as a builtin attribute

[Arthur Cohen via Gcc-cvs]

https://gcc.gnu.org/g:90ce6ea184f1b94e1bd1c88d4f99a9e055de3d97

commit r15-2585-g90ce6ea184f1b94e1bd1c88d4f99a9e055de3d97
Author: Owen Avery <powerboat9.ga...@gmail.com>
Date:   Tue Mar 26 19:28:53 2024 -0400

    gccrs: Recognize unstable as a builtin attribute
    
    gcc/rust/ChangeLog:
    
            * util/rust-attribute-values.h
            (Attributes::UNSTABLE): New.
            * util/rust-attributes.cc
            (__definitions): Add Attributes::UNSTABLE.
    
    gcc/testsuite/ChangeLog:
    
            * rust/compile/unstable-fn.rs: New test.
    
    Signed-off-by: Owen Avery <powerboat9.ga...@gmail.com>

Diff:
---
 gcc/rust/util/rust-attribute-values.h     | 1 +
 gcc/rust/util/rust-attributes.cc          | 3 ++-
 gcc/testsuite/rust/compile/unstable-fn.rs | 2 ++
 3 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/gcc/rust/util/rust-attribute-values.h 
b/gcc/rust/util/rust-attribute-values.h
index 04aef99be68f..a8551c07dba6 100644
--- a/gcc/rust/util/rust-attribute-values.h
+++ b/gcc/rust/util/rust-attribute-values.h
@@ -52,6 +52,7 @@ public:
   static constexpr auto &RUSTC_INHERIT_OVERFLOW_CHECKS
     = "rustc_inherit_overflow_checks";
   static constexpr auto &STABLE = "stable";
+  static constexpr auto &UNSTABLE = "unstable";
 };
 } // namespace Values
 } // namespace Rust
diff --git a/gcc/rust/util/rust-attributes.cc b/gcc/rust/util/rust-attributes.cc
index e10918b2f8d0..84d1781d0b36 100644
--- a/gcc/rust/util/rust-attributes.cc
+++ b/gcc/rust/util/rust-attributes.cc
@@ -60,7 +60,8 @@ static const BuiltinAttrDefinition __definitions[]
      // #![feature(rustc_attrs)]
      {Attrs::RUSTC_DEPRECATED, STATIC_ANALYSIS},
      {Attrs::RUSTC_INHERIT_OVERFLOW_CHECKS, CODE_GENERATION},
-     {Attrs::STABLE, STATIC_ANALYSIS}};
+     {Attrs::STABLE, STATIC_ANALYSIS},
+     {Attrs::UNSTABLE, STATIC_ANALYSIS}};
 
 BuiltinAttributeMappings *
 BuiltinAttributeMappings::get ()
diff --git a/gcc/testsuite/rust/compile/unstable-fn.rs 
b/gcc/testsuite/rust/compile/unstable-fn.rs
new file mode 100644
index 000000000000..4cbbebdb50e0
--- /dev/null
+++ b/gcc/testsuite/rust/compile/unstable-fn.rs
@@ -0,0 +1,2 @@
+#[unstable(feature = "some_feature", issue = "12345")]
+pub fn foo() {}