3 files changed, 42 insertions, 9 deletions

diff --git a/gcc/rust/backend/rust-compile-base.cc b/gcc/rust/backend/rust-compile-base.cc
index 6773ac6..7b0a375 100644
--- a/gcc/rust/backend/rust-compile-base.cc
+++ b/gcc/rust/backend/rust-compile-base.cc
@@ -343,8 +343,12 @@ HIRCompileBase::compile_locals_for_block (Context *ctx, Resolver::Rib &rib,
       rust_assert (ok);
 
       HIR::Stmt *decl = nullptr;
-      ok = ctx->get_mappings ()->resolve_nodeid_to_stmt (d.parent, &decl);
-      rust_assert (ok);
+      if (!ctx->get_mappings ()->resolve_nodeid_to_stmt (d.parent, &decl))
+	{
+	  // might be an extern block see fix for
+	  // https://github.com/Rust-GCC/gccrs/issues/976
+	  continue;
+	}
 
       // if its a function we extract this out side of this fn context
       // and it is not a local to this function
diff --git a/gcc/rust/backend/rust-compile-extern.h b/gcc/rust/backend/rust-compile-extern.h
index 1987805..c24437d 100644
--- a/gcc/rust/backend/rust-compile-extern.h
+++ b/gcc/rust/backend/rust-compile-extern.h
@@ -29,11 +29,19 @@ class CompileExternItem : public HIRCompileBase,
 			  public HIR::HIRExternalItemVisitor
 {
 public:
-  static void compile (HIR::ExternalItem *item, Context *ctx,
-		       TyTy::BaseType *concrete = nullptr)
+  static tree compile (HIR::ExternalItem *item, Context *ctx,
+		       TyTy::BaseType *concrete = nullptr,
+		       bool is_query_mode = false,
+		       Location ref_locus = Location ())
   {
-    CompileExternItem compiler (ctx, concrete);
+    CompileExternItem compiler (ctx, concrete, ref_locus);
     item->accept_vis (compiler);
+
+    if (is_query_mode && compiler.reference == error_mark_node)
+      rust_internal_error_at (ref_locus, "failed to compile extern item: %s",
+			      item->as_string ().c_str ());
+
+    return compiler.reference;
   }
 
   void visit (HIR::ExternalStaticItem &item) override
@@ -58,6 +66,8 @@ public:
 					      item.get_locus ());
     ctx->insert_var_decl (item.get_mappings ().get_hirid (), static_global);
     ctx->push_var (static_global);
+
+    reference = ctx->get_backend ()->var_expression (static_global, ref_locus);
   }
 
   void visit (HIR::ExternalFunctionItem &function) override
@@ -129,14 +139,21 @@ public:
     setup_abi_options (fndecl, fntype->get_abi ());
 
     ctx->insert_function_decl (fntype, fndecl);
+
+    reference
+      = address_expression (fndecl, build_pointer_type (TREE_TYPE (fndecl)),
+			    ref_locus);
   }
 
 private:
-  CompileExternItem (Context *ctx, TyTy::BaseType *concrete)
-    : HIRCompileBase (ctx), concrete (concrete)
+  CompileExternItem (Context *ctx, TyTy::BaseType *concrete, Location ref_locus)
+    : HIRCompileBase (ctx), concrete (concrete), reference (error_mark_node),
+      ref_locus (ref_locus)
   {}
 
   TyTy::BaseType *concrete;
+  tree reference;
+  Location ref_locus;
 };
 
 } // namespace Compile
diff --git a/gcc/rust/backend/rust-compile-resolve-path.cc b/gcc/rust/backend/rust-compile-resolve-path.cc
index bd44bf4..ca96a27 100644
--- a/gcc/rust/backend/rust-compile-resolve-path.cc
+++ b/gcc/rust/backend/rust-compile-resolve-path.cc
@@ -23,8 +23,7 @@
 #include "rust-compile-expr.h"
 #include "rust-hir-trait-resolve.h"
 #include "rust-hir-path-probe.h"
-
-#include "print-tree.h"
+#include "rust-compile-extern.h"
 
 namespace Rust {
 namespace Compile {
@@ -172,7 +171,11 @@ HIRCompileBase::query_compile (HirId ref, TyTy::BaseType *lookup,
 {
   HIR::Item *resolved_item
     = ctx->get_mappings ()->lookup_hir_item (mappings.get_crate_num (), ref);
+  HIR::ExternalItem *resolved_extern_item
+    = ctx->get_mappings ()->lookup_hir_extern_item (mappings.get_crate_num (),
+						    ref);
   bool is_hir_item = resolved_item != nullptr;
+  bool is_hir_extern_item = resolved_extern_item != nullptr;
   if (is_hir_item)
     {
       if (!lookup->has_subsititions_defined ())
@@ -182,6 +185,15 @@ HIRCompileBase::query_compile (HirId ref, TyTy::BaseType *lookup,
 	return CompileItem::compile (resolved_item, ctx, lookup, true,
 				     expr_locus);
     }
+  else if (is_hir_extern_item)
+    {
+      if (!lookup->has_subsititions_defined ())
+	return CompileExternItem::compile (resolved_extern_item, ctx, nullptr,
+					   true, expr_locus);
+      else
+	return CompileExternItem::compile (resolved_extern_item, ctx, lookup,
+					   true, expr_locus);
+    }
   else
     {
       HirId parent_impl_id = UNKNOWN_HIRID;