1 files changed, 22 insertions, 0 deletions
diff --git a/gcc/rust/expand/rust-macro-builtins.cc b/gcc/rust/expand/rust-macro-builtins.cc
index b7bbd32..ce0be92 100644
--- a/gcc/rust/expand/rust-macro-builtins.cc
+++ b/gcc/rust/expand/rust-macro-builtins.cc
@@ -18,8 +18,20 @@
 
 #include "rust-macro-builtins.h"
 #include "rust-diagnostics.h"
+#include "rust-expr.h"
+#include "rust-session-manager.h"
 
 namespace Rust {
+namespace {
+std::unique_ptr<AST::Expr>
+make_string (Location locus, std::string value)
+{
+  return std::unique_ptr<AST::Expr> (
+    new AST::LiteralExpr (value, AST::Literal::STRING,
+			  PrimitiveCoreType::CORETYPE_STR, {}, locus));
+}
+} // namespace
+
 AST::ASTFragment
 MacroBuiltin::assert (Location invoc_locus, AST::MacroInvocData &invoc)
 {
@@ -27,4 +39,14 @@ MacroBuiltin::assert (Location invoc_locus, AST::MacroInvocData &invoc)
 
   return AST::ASTFragment::create_empty ();
 }
+
+AST::ASTFragment
+MacroBuiltin::file (Location invoc_locus, AST::MacroInvocData &invoc)
+{
+  auto current_file
+    = Session::get_instance ().linemap->location_file (invoc_locus);
+  auto file_str = AST::SingleASTNode (make_string (invoc_locus, current_file));
+
+  return AST::ASTFragment ({file_str});
+}
 } // namespace Rust