lang.opt, [...]: New flag -finit-derived.

lang.opt, [...]: New flag -finit-derived.

2016-08-15  Fritz Reese  <fritzoreese@gmail.com>

	gcc/fortran/
	* lang.opt, invoke.texi: New flag -finit-derived.
	* gfortran.h (gfc_build_default_init_expr, gfc_apply_init,
	gfc_generate_initializer): New prototypes.
	* expr.c (gfc_build_default_init_expr, gfc_apply_init,
	component_initializer, gfc_generate_initializer): New functions.
	* expr.c (gfc_default_initializer): Wrap gfc_generate_initializer.
	* decl.c (build_struct): Move common code to gfc_apply_init.
	* resolve.c (can_generate_init): New function.
	* resolve.c (build_default_init_expr): Wrap gfc_build_default_init_expr.
	* resolve.c (apply_default_init, resolve_fl_variable_derived): Use
	gfc_generate_initializer.
	* trans-decl.c (gfc_generate_function_code): Use
	gfc_generate_initializer.

	gcc/testsuite/gfortran.dg/
	* init_flag_13.f90: New testcase.
	* init_flag_14.f90: Ditto.
	* init_flag_15.f03: Ditto.
	* dec_init_1.f90: Ditto.
	* dec_init_2.f90: Ditto.

From-SVN: r239489