[COMMITTED 032/143] gccrs: Improve handling of non-final path segments

[arthur . cohen]

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

gcc/rust/ChangeLog:

        * resolve/rust-forever-stack.hxx
        (ForeverStack::resolve_segments): Remove usage of optional
        reference, allow non-final path segments to resolve to types
        even outside the type namespace, and allow resolution to
        progress past non-final path segments which resolve to modules.

gcc/testsuite/ChangeLog:

        * rust/compile/use_3.rs: New test.

Signed-off-by: Owen Avery <powerboat9.ga...@gmail.com>
---
 gcc/rust/resolve/rust-forever-stack.hxx | 21 ++++++++++++++-------
 gcc/testsuite/rust/compile/use_3.rs     | 10 ++++++++++
 2 files changed, 24 insertions(+), 7 deletions(-)
 create mode 100644 gcc/testsuite/rust/compile/use_3.rs

diff --git a/gcc/rust/resolve/rust-forever-stack.hxx 
b/gcc/rust/resolve/rust-forever-stack.hxx
index 1ed87b3d55b..848f5e61522 100644
--- a/gcc/rust/resolve/rust-forever-stack.hxx
+++ b/gcc/rust/resolve/rust-forever-stack.hxx
@@ -531,7 +531,7 @@ ForeverStack<N>::resolve_segments (
                                       || seg.is_lower_self_seg ()))
        return tl::nullopt;
 
-      tl::optional<typename ForeverStack<N>::Node &> child = tl::nullopt;
+      tl::optional<std::reference_wrapper<Node>> child = tl::nullopt;
 
       /*
        * On every iteration this loop either
@@ -583,10 +583,17 @@ ForeverStack<N>::resolve_segments (
              break;
            }
 
-         if (N == Namespace::Types)
+         auto rib_lookup = current_node->rib.get (seg.as_string ());
+         if (rib_lookup && !rib_lookup->is_ambiguous ())
            {
-             auto rib_lookup = current_node->rib.get (seg.as_string ());
-             if (rib_lookup && !rib_lookup->is_ambiguous ())
+             if (Analysis::Mappings::get ()
+                   .lookup_glob_container (rib_lookup->get_node_id ())
+                   .has_value ())
+               {
+                 child = dfs_node (root, rib_lookup->get_node_id ()).value ();
+                 break;
+               }
+             else
                {
                  insert_segment_resolution (outer_seg,
                                             rib_lookup->get_node_id ());
@@ -611,9 +618,9 @@ ForeverStack<N>::resolve_segments (
          current_node = &current_node->parent.value ();
        }
 
-      // if child didn't contain a value
-      // the while loop above should have return'd or kept looping
-      current_node = &child.value ();
+      // if child didn't point to a value
+      // the while loop above would have returned or kept looping
+      current_node = &child->get ();
       insert_segment_resolution (outer_seg, current_node->id);
     }
 
diff --git a/gcc/testsuite/rust/compile/use_3.rs 
b/gcc/testsuite/rust/compile/use_3.rs
new file mode 100644
index 00000000000..2cfe38f47b2
--- /dev/null
+++ b/gcc/testsuite/rust/compile/use_3.rs
@@ -0,0 +1,10 @@
+mod intrinsic {
+    pub fn foo() {}
+}
+
+pub mod a {
+    pub fn b() {
+        use crate::intrinsic;
+        intrinsic::foo();
+    }
+}
-- 
2.50.1