PR exp/15364:
	* eval.c (evaluate_subexp_standard) <STRUCTOP_STRUCT,
	STRUCTOP_PTR>: Return a not_lval value for
	EVAL_AVOID_SIDE_EFFECTS.
	* opencl-lang.c (evaluate_subexp_opencl): Return a not_lval value
	for EVAL_AVOID_SIDE_EFFECTS.
gdb/testsuite
	* gdb.base/exprs.exp (test_expr): Add regression test.
	* gdb.base/exprs.c (null_t_struct): New global.
    	PR gdb/15538:
	* dwarf2read.c (dwarf2_record_block_ranges): Ensure that the
	ranges section has been read.
fix PR number in ChangeLog