re PR lto/65015 (LTO produces randomly ordered debug information)

2015-02-16  Richard Biener  <rguenther@suse.de>

	PR lto/65015
	* varasm.c (default_file_start): For LTO produced units
	emit <artificial> as file directive.

From-SVN: r220735

gcc/ChangeLog

 2015-02-16  Richard Biener  <rguenther@suse.de>
 
+	PR lto/65015
+	* varasm.c (default_file_start): For LTO produced units
+	emit <artificial> as file directive.
+
+2015-02-16  Richard Biener  <rguenther@suse.de>
+
 	PR tree-optimization/63593
 	* tree-predcom.c (execute_pred_commoning_chain): Delay removing
 	stmts and releasing SSA names until...

gcc/varasm.c

@@ -7043,7 +7043,13 @@ default_file_start (void)
     fputs (ASM_APP_OFF, asm_out_file);
 
   if (targetm.asm_file_start_file_directive)
-    output_file_directive (asm_out_file, main_input_filename);
+    {
+      /* LTO produced units have no meaningful main_input_filename.  */
+      if (in_lto_p)
+	output_file_directive (asm_out_file, "<artificial>");
+      else
+	output_file_directive (asm_out_file, main_input_filename);
+    }
 }
 
 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END