[gcc r17-3123] gccrs: Handle ambiguous glob imports

https://gcc.gnu.org/g:c4d353b7c99d6b1fcbcc55115db4287ab5e4661c

commit r17-3123-gc4d353b7c99d6b1fcbcc55115db4287ab5e4661c
Author: Owen Avery <[email protected]>
Date:   Thu Jul 23 23:50:20 2026 -0400

    gccrs: Handle ambiguous glob imports
    
    gcc/rust/ChangeLog:
    
            * resolve/rust-finalize-imports-2.0.cc
            (GlobbingVisitor::glob_definitions): Offload details to
            Rib::insert_globbed.
            (GlobbingVisitor::glob_definition): Remove member function
            definition.
            * resolve/rust-finalize-imports-2.0.h
            (GlobbingVisitor::glob_definition): Remove member function
            declaration.
            * resolve/rust-rib.cc (Rib::insert_globbed): New member function
            definition.
            * resolve/rust-rib.h (Rib::insert_globbed): New member function
            declaration.
    
    gcc/testsuite/ChangeLog:
    
            * rust/compile/glob-import-ambiguous.rs: New test.
    
    Signed-off-by: Owen Avery <[email protected]>

Diff:
---
 gcc/rust/resolve/rust-finalize-imports-2.0.cc      | 23 +--------------
 gcc/rust/resolve/rust-finalize-imports-2.0.h       |  2 --
 gcc/rust/resolve/rust-rib.cc                       | 34 ++++++++++++++++++++++
 gcc/rust/resolve/rust-rib.h                        | 10 +++++++
 .../rust/compile/glob-import-ambiguous.rs          | 26 +++++++++++++++++
 5 files changed, 71 insertions(+), 24 deletions(-)

diff --git a/gcc/rust/resolve/rust-finalize-imports-2.0.cc b/gcc/rust/resolve/rust-finalize-imports-2.0.cc
index 7fbbb921a258..06e61a04c7fe 100644
--- a/gcc/rust/resolve/rust-finalize-imports-2.0.cc
+++ b/gcc/rust/resolve/rust-finalize-imports-2.0.cc
@@ -68,28 +68,7 @@ void
 GlobbingVisitor::glob_definitions (Rib &dst, Rib &src)
 {
   for (auto &ent : src.get_values ())
-    {
-      auto globbed = glob_definition (ent.second);
-      if (globbed.has_value ())
-	{
-	  auto res = dst.insert (ent.first, globbed.value ());
-	  // inserting a globbed definition should (?) always succeed
-	  // TODO: double check
-	  rust_assert (res.has_value ()
-		       || res.error ().existing
-			    == globbed.value ().get_node_id ());
-	  dirty |= res.has_value ();
-	}
-    }
-}
-
-tl::optional<Rib::Definition>
-GlobbingVisitor::glob_definition (const Rib::Definition &def)
-{
-  // TODO: normal error?
-  rust_assert (!def.is_ambiguous ());
-
-  return Rib::Definition::Globbed (def.get_node_id ());
+    dirty |= dst.insert_globbed (ent.first, ent.second);
 }
 
 } // namespace Resolver2_0
diff --git a/gcc/rust/resolve/rust-finalize-imports-2.0.h b/gcc/rust/resolve/rust-finalize-imports-2.0.h
index dfbd1fe9a071..4e3c1e92d258 100644
--- a/gcc/rust/resolve/rust-finalize-imports-2.0.h
+++ b/gcc/rust/resolve/rust-finalize-imports-2.0.h
@@ -39,8 +39,6 @@ public:
 
   void glob_definitions (Rib &dst, Rib &src);
 
-  tl::optional<Rib::Definition> glob_definition (const Rib::Definition &def);
-
   bool is_dirty () const { return dirty; }
 
 private:
diff --git a/gcc/rust/resolve/rust-rib.cc b/gcc/rust/resolve/rust-rib.cc
index 73e7f70e51a1..5ddd0293dc14 100644
--- a/gcc/rust/resolve/rust-rib.cc
+++ b/gcc/rust/resolve/rust-rib.cc
@@ -174,6 +174,40 @@ Rib::insert (std::string name, Definition def)
   return def.ids_globbed.back ();
 }
 
+bool
+Rib::insert_globbed (std::string name, const Definition &def)
+{
+  bool dirty = false;
+
+  const std::vector<NodeId> *ids_src;
+
+  if (!def.ids_shadowable.empty ())
+    ids_src = &def.ids_shadowable;
+  else if (!def.ids_non_shadowable.empty ())
+    ids_src = &def.ids_non_shadowable;
+  else
+    ids_src = &def.ids_globbed;
+
+  auto it = values.find (name);
+  if (it == values.end ())
+    {
+      values[name].ids_globbed = *ids_src;
+      return true;
+    }
+
+  for (NodeId id : *ids_src)
+    {
+      auto &ids_dst = it->second.ids_globbed;
+      if (std::find (ids_dst.cbegin (), ids_dst.cend (), id) == ids_dst.cend ())
+	{
+	  dirty = true;
+	  ids_dst.push_back (id);
+	}
+    }
+
+  return dirty;
+}
+
 tl::optional<Rib::Definition>
 Rib::get (const std::string &name)
 {
diff --git a/gcc/rust/resolve/rust-rib.h b/gcc/rust/resolve/rust-rib.h
index c5de20bc8c12..96d1220933ce 100644
--- a/gcc/rust/resolve/rust-rib.h
+++ b/gcc/rust/resolve/rust-rib.h
@@ -245,6 +245,16 @@ public:
   tl::expected<NodeId, DuplicateNameError> insert (std::string name,
 						   Definition def);
 
+  /**
+   * Insert a new node, but as a glob import, in the rib
+   *
+   * @param name The name associated with the AST node
+   * @param def The `Definition` to insert
+   *
+   * @return true if the insertion wasn't redundant
+   */
+  bool insert_globbed (std::string name, const Definition &def);
+
   /**
    * Access an inserted NodeId.
    *
diff --git a/gcc/testsuite/rust/compile/glob-import-ambiguous.rs b/gcc/testsuite/rust/compile/glob-import-ambiguous.rs
new file mode 100644
index 000000000000..62be7dab08e5
--- /dev/null
+++ b/gcc/testsuite/rust/compile/glob-import-ambiguous.rs
@@ -0,0 +1,26 @@
+#![feature(no_core)]
+#![no_core]
+
+mod a {
+    pub fn x() {}
+    pub fn y() {}
+}
+
+mod b {
+    pub fn x() {}
+    pub fn z() {}
+}
+
+mod c {
+    pub use crate::a::*;
+    pub use crate::b::*;
+}
+
+pub fn main() -> i32 {
+    use crate::c::*;
+    a::x();
+    b::x();
+    y();
+    z();
+    0
+}