PR c/61077
c-family/
	* c-common.c (check_main_parameter_types): Warn for _Atomic-qualified
	parameter type of main.
c/
	* c-decl.c (start_function): Warn for _Atomic-qualified return type
	of main.
testsuite/
	* gcc.dg/pr61077.c: New test.

From-SVN: r210229