re PR fortran/57160 (short-circuit IF only with -ffrontend-optimize)

re PR fortran/57160 (short-circuit IF only with -ffrontend-optimize)

2018-08-10  Janus Weil  <janus@gcc.gnu.org>

	PR fortran/57160
	* invoke.texi (frontend-optimize): Mention short-circuiting.
	* options.c (gfc_post_options): Disable -ffrontend-optimize with -Og.
	* resolve.c (resolve_operator): Warn about short-circuiting only with
	-ffrontend-optimize.
	* trans-expr.c (gfc_conv_expr_op): Use short-circuiting operators only
	with -ffrontend-optimize. Without that flag, make sure that both
	operands are evaluated.

2018-08-10  Janus Weil  <janus@gcc.gnu.org>

	PR fortran/57160
	* gfortran.dg/actual_pointer_function_1.f90: Fix invalid test case.
	* gfortran.dg/inline_matmul_23.f90: Add option "-ffrontend-optimize".
	* gfortran.dg/short_circuiting_2.f90: New test case.
	* gfortran.dg/short_circuiting_3.f90: New test case.

From-SVN: r263471