[gccrs COMMIT] gccrs: Fix type param forward declare check

[gerris . rs]

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

Type param bounds are allowed to use forward declared generic
parameters.

gcc/rust/ChangeLog:

        * resolve/rust-default-resolver.cc
        (DefaultResolver::visit (TypeParam)): Visit bounds outside of
        ForwardTypeParamBan rib.

gcc/testsuite/ChangeLog:

        * rust/compile/generics15.rs: New test.

Signed-off-by: Owen Avery <powerboat9.ga...@gmail.com>
---
This change was merged into the gccrs repository and is posted here for
upstream visibility and potential drive-by review, as requested by GCC
release managers.
Each commit email contains a link to its details on github from where you can
find the Pull-Request and associated discussions.


Commit on github: 
https://github.com/Rust-GCC/gccrs/commit/76fc766f34824f3d4695dbc805a9bf58e19788be

The commit has NOT been mentioned in any issue.

The commit has been mentioned in the following pull-request(s):
 - https://github.com/Rust-GCC/gccrs/pull/4684

 gcc/rust/resolve/rust-default-resolver.cc | 12 ++++++++++--
 gcc/testsuite/rust/compile/generics15.rs  |  9 +++++++++
 2 files changed, 19 insertions(+), 2 deletions(-)
 create mode 100644 gcc/testsuite/rust/compile/generics15.rs

diff --git a/gcc/rust/resolve/rust-default-resolver.cc 
b/gcc/rust/resolve/rust-default-resolver.cc
index 10f506bb2..ba6530868 100644
--- a/gcc/rust/resolve/rust-default-resolver.cc
+++ b/gcc/rust/resolve/rust-default-resolver.cc
@@ -433,9 +433,17 @@ DefaultResolver::visit (AST::StaticItem &item)
 void
 DefaultResolver::visit (AST::TypeParam &param)
 {
-  auto expr_vis = [this, &param] () { AST::DefaultASTVisitor::visit (param); };
+  auto param_ban_vis = [this, &param] () {
+    visit_outer_attrs (param);
+    if (param.has_type ())
+      visit (param.get_type ());
+  };
+
+  ctx.scoped (Rib::Kind::ForwardTypeParamBan, param.get_node_id (),
+             param_ban_vis);
 
-  ctx.scoped (Rib::Kind::ForwardTypeParamBan, param.get_node_id (), expr_vis);
+  for (auto &bound : param.get_type_param_bounds ())
+    visit (bound);
 }
 
 void
diff --git a/gcc/testsuite/rust/compile/generics15.rs 
b/gcc/testsuite/rust/compile/generics15.rs
new file mode 100644
index 000000000..bb50be4e8
--- /dev/null
+++ b/gcc/testsuite/rust/compile/generics15.rs
@@ -0,0 +1,9 @@
+#![feature(no_core, lang_items)]
+#![no_core]
+
+#[lang = "sized"]
+pub trait Sized {}
+
+pub trait A<T> {}
+
+pub struct B<T: A<T>> (T);

base-commit: 0e19cee2e9b0b004f3ce6aaded424c2d3a072f26
-- 
2.54.0