[COMMITTED 056/145] gccrs: Allow rustc_const_stable and rustc_const_unstable

[arthur . cohen]

From: Owen Avery <powerboat9.ga...@gmail.com>

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>
---
 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(-)
 create mode 100644 gcc/testsuite/rust/compile/rustc_const_unstable.rs

diff --git a/gcc/rust/expand/rust-macro-builtins.cc 
b/gcc/rust/expand/rust-macro-builtins.cc
index ed6c0e9db97..61b677ac075 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 e51ec076670..fec73b17c3e 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 aef51b7f4b1..c9e376400fd 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 9208b1ab3b6..a45355de6b3 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 00000000000..6cedefade72
--- /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() {}
-- 
2.45.2