[gcc r15-8145] gccrs: Allow rustc_const_stable and rustc_const_unstable

[Arthur Cohen via Gcc-cvs]

https://gcc.gnu.org/g:d602f4694c6211720ea0854976342e958afc65ed

commit r15-8145-gd602f4694c6211720ea0854976342e958afc65ed
Author: Owen Avery <powerboat9.ga...@gmail.com>
Date:   Wed Feb 28 21:00:08 2024 -0500

    gccrs: Allow rustc_const_stable and rustc_const_unstable
    
    gcc/rust/ChangeLog:
    
            * expand/rust-macro-builtins.cc
            (MacroBuiltin::builtin_transcribers):
            Add entries for "rustc_const_stable" and "rustc_const_unstable".
            * util/rust-attributes.cc
            (__definitions): Add entries for RUSTC_CONST_STABLE and
            RUSTC_CONST_UNSTABLE.
            * util/rust-attribute-values.h
            (Attributes::RUSTC_CONST_STABLE): New.
            (Attributes::RUSTC_CONST_UNSTABLE): New.
    
    gcc/testsuite/ChangeLog:
    
            * rust/compile/rustc_const_stable.rs:
            Enable feature rustc_attrs, expect no errors.
            * rust/compile/rustc_const_unstable.rs: New test.
    
    Signed-off-by: Owen Avery <powerboat9.ga...@gmail.com>

Diff:
---
 gcc/rust/expand/rust-macro-builtins.cc             | 2 ++
 gcc/rust/util/rust-attribute-values.h              | 2 ++
 gcc/rust/util/rust-attributes.cc                   | 5 ++++-
 gcc/testsuite/rust/compile/rustc_const_stable.rs   | 4 +++-
 gcc/testsuite/rust/compile/rustc_const_unstable.rs | 4 ++++
 5 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/gcc/rust/expand/rust-macro-builtins.cc 
b/gcc/rust/expand/rust-macro-builtins.cc
index ed6c0e9db973..61b677ac0754 100644
--- a/gcc/rust/expand/rust-macro-builtins.cc
+++ b/gcc/rust/expand/rust-macro-builtins.cc
@@ -123,6 +123,8 @@ std::unordered_map<std::string, AST::MacroTranscriberFunc>
     {"test_case", MacroBuiltin::sorry},
     {"global_allocator", MacroBuiltin::sorry},
     {"cfg_accessible", MacroBuiltin::sorry},
+    {"rustc_const_stable", MacroBuiltin::sorry},
+    {"rustc_const_unstable", MacroBuiltin::sorry},
     /* Derive builtins do not need a real transcriber, but still need one. It
        should however never be called since builtin derive macros get expanded
        differently, and benefit from knowing on what kind of items they are
diff --git a/gcc/rust/util/rust-attribute-values.h 
b/gcc/rust/util/rust-attribute-values.h
index e51ec0766706..fec73b17c3ed 100644
--- a/gcc/rust/util/rust-attribute-values.h
+++ b/gcc/rust/util/rust-attribute-values.h
@@ -53,6 +53,8 @@ public:
     = "rustc_inherit_overflow_checks";
   static constexpr auto &STABLE = "stable";
   static constexpr auto &UNSTABLE = "unstable";
+  static constexpr auto &RUSTC_CONST_STABLE = "rustc_const_stable";
+  static constexpr auto &RUSTC_CONST_UNSTABLE = "rustc_const_unstable";
 };
 } // namespace Values
 } // namespace Rust
diff --git a/gcc/rust/util/rust-attributes.cc b/gcc/rust/util/rust-attributes.cc
index aef51b7f4b17..c9e376400fdd 100644
--- a/gcc/rust/util/rust-attributes.cc
+++ b/gcc/rust/util/rust-attributes.cc
@@ -61,7 +61,10 @@ static const BuiltinAttrDefinition __definitions[]
      {Attrs::RUSTC_DEPRECATED, STATIC_ANALYSIS},
      {Attrs::RUSTC_INHERIT_OVERFLOW_CHECKS, CODE_GENERATION},
      {Attrs::STABLE, STATIC_ANALYSIS},
-     {Attrs::UNSTABLE, STATIC_ANALYSIS}};
+     {Attrs::UNSTABLE, STATIC_ANALYSIS},
+     // assuming we keep these for static analysis
+     {Attrs::RUSTC_CONST_STABLE, STATIC_ANALYSIS},
+     {Attrs::RUSTC_CONST_UNSTABLE, STATIC_ANALYSIS}};
 
 BuiltinAttributeMappings *
 BuiltinAttributeMappings::get ()
diff --git a/gcc/testsuite/rust/compile/rustc_const_stable.rs 
b/gcc/testsuite/rust/compile/rustc_const_stable.rs
index 9208b1ab3b62..a45355de6b37 100644
--- a/gcc/testsuite/rust/compile/rustc_const_stable.rs
+++ b/gcc/testsuite/rust/compile/rustc_const_stable.rs
@@ -1,2 +1,4 @@
+#![feature(rustc_attrs)]
+
 #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = 
"1.47.0")]
-pub fn foo() {} // { dg-error "macro not found" "" { target *-*-* } .-1 }
+pub fn foo() {}
diff --git a/gcc/testsuite/rust/compile/rustc_const_unstable.rs 
b/gcc/testsuite/rust/compile/rustc_const_unstable.rs
new file mode 100644
index 000000000000..6cedefade720
--- /dev/null
+++ b/gcc/testsuite/rust/compile/rustc_const_unstable.rs
@@ -0,0 +1,4 @@
+#![feature(rustc_attrs)]
+
+#[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = 
"1234")]
+pub fn foo() {}