diff --git a/gcc/rust/rust-lang.cc b/gcc/rust/rust-lang.cc
index 1088845497e..e77644e8bc7 100644
--- a/gcc/rust/rust-lang.cc
+++ b/gcc/rust/rust-lang.cc
@@ -286,6 +286,10 @@ grs_langhook_post_options (const char **pfilename ATTRIBUTE_UNUSED)
 {
   // can be used to override other options if required
 
+  // check for input file
+  if (!*pfilename && num_in_fnames == 0)
+    *pfilename = "-";
+
   // satisfies an assert in init_excess_precision in toplev.cc
   if (flag_excess_precision /*_cmdline*/ == EXCESS_PRECISION_DEFAULT)
     flag_excess_precision /*_cmdline*/ = EXCESS_PRECISION_STANDARD;
diff --git a/gcc/rust/rust-session-manager.cc b/gcc/rust/rust-session-manager.cc
index 64181184683..272279db0e7 100644
--- a/gcc/rust/rust-session-manager.cc
+++ b/gcc/rust/rust-session-manager.cc
@@ -399,6 +399,12 @@ Session::enable_dump (std::string arg)
 void
 Session::handle_input_files (int num_files, const char **files)
 {
+  static const char *stdin_file[] = {"-"};
+  if (num_files == 0)
+    {
+      files = stdin_file;
+      num_files = 1;
+    }
   if (num_files != 1)
     rust_fatal_error (UNDEF_LOCATION,
 		      "only one file may be specified on the command line");