[gcc r13-5559] gccrs: const generics: Make sure const generic types are visited properly

[Arthur Cohen <cohenarthur@gcc.gnu.org>]

https://gcc.gnu.org/g:288b6298a6ae9356122362cd604e3582d8decd26

commit r13-5559-g288b6298a6ae9356122362cd604e3582d8decd26
Author: Arthur Cohen <arthur.cohen@embecosm.com>
Date:   Mon Sep 12 15:53:01 2022 +0200

    gccrs: const generics: Make sure const generic types are visited properly
    
    ...in all contexts.
    
    gcc/testsuite/ChangeLog:
    
            * rust/compile/const_generics_7.rs: New test.

Diff:
---
 gcc/testsuite/rust/compile/const_generics_7.rs | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/gcc/testsuite/rust/compile/const_generics_7.rs b/gcc/testsuite/rust/compile/const_generics_7.rs
new file mode 100644
index 00000000000..2c128db92ea
--- /dev/null
+++ b/gcc/testsuite/rust/compile/const_generics_7.rs
@@ -0,0 +1,17 @@
+struct S<const N: usize>;
+
+pub fn foo<const N: FooBar>() {} // { dg-error "failed to resolve" }
+type Foo<const N: FooBar> = S<N>; // { dg-error "failed to resolve" }
+struct Foo2<const N: FooBar>; // { dg-error "failed to resolve" }
+enum Foo3<const N: FooBar> { // { dg-error "failed to resolve" }
+    Foo,
+    Bar,
+}
+union Foo4<const N: FooBar> { // { dg-error "failed to resolve" }
+    a: usize,
+    b: i32,
+}
+trait Fooable<const N: FooBar> {} // { dg-error "failed to resolve" }
+
+trait Traitable {}
+impl<const N: FooBar> Traitable for Foo2<N> {} // { dg-error "failed to resolve" }