[COMMITTED 41/43] gccrs: Fixed glob-import all ICE

[arthur . cohen]

From: AhmedSaid3617 <said.ahmed3...@gmail.com>

Modified toplevel name resolver to recognize use ::*; and use *; as valid 
import statements, to prevent ICE.

gcc/rust/ChangeLog:

        * ast/rust-item.h:(PathType::get_glob_type): Added const qualifier to 
allow
        function call from const objects.
        * resolve/rust-forever-stack.hxx:
        (ForeverStack<N>::resolve_path): Check for empty segments vector and
        return starting point.
        * resolve/rust-toplevel-name-resolver-2.0.cc (flatten_glob): Preserve 
the
        opening scope resolution property of the use statement.

Signed-off-by: AhmedSaid3617 <said.ahmed3...@gmail.com>
---
 gcc/rust/ast/rust-item.h                      |  2 +-
 gcc/rust/resolve/rust-forever-stack.hxx       | 27 ++++++++++---------
 .../rust-toplevel-name-resolver-2.0.cc        |  4 ++-
 3 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/gcc/rust/ast/rust-item.h b/gcc/rust/ast/rust-item.h
index 91c52d2cc70..0724638f210 100644
--- a/gcc/rust/ast/rust-item.h
+++ b/gcc/rust/ast/rust-item.h
@@ -1078,7 +1078,7 @@ public:
 
   void accept_vis (ASTVisitor &vis) override;
 
-  PathType get_glob_type () { return glob_type; }
+  PathType get_glob_type () const { return glob_type; }
 
   Kind get_kind () const override { return Glob; }
 
diff --git a/gcc/rust/resolve/rust-forever-stack.hxx 
b/gcc/rust/resolve/rust-forever-stack.hxx
index e8f4e8449b3..c7f90ae3a21 100644
--- a/gcc/rust/resolve/rust-forever-stack.hxx
+++ b/gcc/rust/resolve/rust-forever-stack.hxx
@@ -729,21 +729,24 @@ ForeverStack<N>::resolve_path (
     }
   else
     {
-      rust_assert (!path.get_segments ().empty ());
+      switch (mode)
+       {
+       case ResolutionMode::Normal:
+         break; // default
+       case ResolutionMode::FromRoot:
+         starting_point = root;
+         break;
+       case ResolutionMode::FromExtern:
+         starting_point = extern_prelude;
+         break;
+       default:
+         rust_unreachable ();
+       }
     }
 
-  switch (mode)
+  if (path.get_segments ().empty ())
     {
-    case ResolutionMode::Normal:
-      break; // default
-    case ResolutionMode::FromRoot:
-      starting_point = root;
-      break;
-    case ResolutionMode::FromExtern:
-      starting_point = extern_prelude;
-      break;
-    default:
-      rust_unreachable ();
+      return Rib::Definition::NonShadowable (starting_point.get ().id);
     }
 
   auto &segments = path.get_segments ();
diff --git a/gcc/rust/resolve/rust-toplevel-name-resolver-2.0.cc 
b/gcc/rust/resolve/rust-toplevel-name-resolver-2.0.cc
index 630b5ab8b95..84961ae2e59 100644
--- a/gcc/rust/resolve/rust-toplevel-name-resolver-2.0.cc
+++ b/gcc/rust/resolve/rust-toplevel-name-resolver-2.0.cc
@@ -504,7 +504,9 @@ flatten_glob (const AST::UseTreeGlob &glob, 
std::vector<AST::SimplePath> &paths,
   if (glob.has_path ())
     paths.emplace_back (glob.get_path ());
   else
-    paths.emplace_back (AST::SimplePath ({}, false, glob.get_locus ()));
+    paths.emplace_back (AST::SimplePath (
+      {}, glob.get_glob_type () == AST::UseTreeGlob::PathType::GLOBAL,
+      glob.get_locus ()));
 }
 
 static bool
-- 
2.50.1