[gcc r15-9086] gccrs: Fix validation of constant items

[Arthur Cohen via Gcc-cvs]

https://gcc.gnu.org/g:f100bd794c26126c37ef7e3e9cb023a06735f429

commit r15-9086-gf100bd794c26126c37ef7e3e9cb023a06735f429
Author: Owen Avery <powerboat9.ga...@gmail.com>
Date:   Tue Mar 25 18:18:21 2025 -0400

    gccrs: Fix validation of constant items
    
    gcc/rust/ChangeLog:
    
            * checks/errors/rust-ast-validation.cc
            (ASTValidation::visit): Allow constant items lacking expressions
            if and only if they're associated with a trait definition, not a
            trait implementation.
    
    gcc/testsuite/ChangeLog:
    
            * rust/compile/issue-3541-1.rs: New test.
            * rust/compile/issue-3541-2.rs: Likewise.
    
    Signed-off-by: Owen Avery <powerboat9.ga...@gmail.com>

Diff:
---
 gcc/rust/checks/errors/rust-ast-validation.cc | 2 +-
 gcc/testsuite/rust/compile/issue-3541-1.rs    | 5 +++++
 gcc/testsuite/rust/compile/issue-3541-2.rs    | 3 +++
 3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/gcc/rust/checks/errors/rust-ast-validation.cc 
b/gcc/rust/checks/errors/rust-ast-validation.cc
index 59b28057bab5..0f4bdeb6935f 100644
--- a/gcc/rust/checks/errors/rust-ast-validation.cc
+++ b/gcc/rust/checks/errors/rust-ast-validation.cc
@@ -56,7 +56,7 @@ ASTValidation::visit (AST::LoopLabel &label)
 void
 ASTValidation::visit (AST::ConstantItem &const_item)
 {
-  if (!const_item.has_expr () && ctx.peek () != Kind::TRAIT_IMPL)
+  if (!const_item.has_expr () && ctx.peek () != Kind::TRAIT)
     {
       rust_error_at (const_item.get_locus (),
                     "associated constant in %<impl%> without body");
diff --git a/gcc/testsuite/rust/compile/issue-3541-1.rs 
b/gcc/testsuite/rust/compile/issue-3541-1.rs
new file mode 100644
index 000000000000..6b47b7e11a52
--- /dev/null
+++ b/gcc/testsuite/rust/compile/issue-3541-1.rs
@@ -0,0 +1,5 @@
+impl B for u32 {
+    const BAR: i32; // { dg-error "associated constant in .impl." }
+}
+
+trait B {}
diff --git a/gcc/testsuite/rust/compile/issue-3541-2.rs 
b/gcc/testsuite/rust/compile/issue-3541-2.rs
new file mode 100644
index 000000000000..9f17eedab54c
--- /dev/null
+++ b/gcc/testsuite/rust/compile/issue-3541-2.rs
@@ -0,0 +1,3 @@
+trait B {
+    const BAR: i32;
+}