--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libphobos/libdruntime/__entrypoint.di	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,56 @@
+/* GDC -- D front-end for GCC
+   Copyright (C) 2013-2020 Free Software Foundation, Inc.
+
+   GCC is free software; you can redistribute it and/or modify it under
+   the terms of the GNU General Public License as published by the Free
+   Software Foundation; either version 3, or (at your option) any later
+   version.
+
+   GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+   WARRANTY; without even the implied warranty of MERCHANTABILITY or
+   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+   for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with GCC; see the file COPYING3.  If not see
+   <http://www.gnu.org/licenses/>.
+*/
+
+/* This module provides the C main() function supplied by the user's program.  */
+
+module __entrypoint;
+
+extern(C):
+
+/* The D main() function supplied by the user's program
+
+   It always has `_Dmain` symbol name and uses C calling convention.
+   But D frontend returns its type as `extern(D)` because of Issue 9028.
+   As we need to deal with actual calling convention we have to mark it
+   as `extern(C)` and use its symbol name.
+*/
+
+int _Dmain(char[][] args);
+int _d_run_main(int argc, char **argv, void* mainFunc);
+
+/* Substitutes for the C main() function.  Just calls into d_run_main with
+   the default main function.  Applications are free to implement their own
+   main function and call the _d_run_main function themselves with any main
+   function.
+*/
+
+int main(int argc, char **argv)
+{
+    return _d_run_main(argc, argv, &_Dmain);
+}
+
+/* This is apparently needed on Solaris because the C tool chain seems to
+   expect the main function to be called _main.  It needs both not just one!
+*/
+
+version (Solaris)
+int _main(int argc, char** argv)
+{
+    return main(argc, argv);
+}
+