PR c++/80560 - warn on undefined memory operations involving non-trivial types

PR c++/80560 - warn on undefined memory operations involving non-trivial types

gcc/c-family/ChangeLog:

	PR c++/80560
	* c.opt (-Wclass-memaccess): New option.

gcc/cp/ChangeLog:

	PR c++/80560
	* call.c (first_non_public_field, maybe_warn_class_memaccess): New
	functions.
	(has_trivial_copy_assign_p, has_trivial_copy_p): Ditto.
	(build_cxx_call): Call maybe_warn_class_memaccess.

gcc/ChangeLog:

	PR c++/80560
	* dumpfile.c (dump_register): Avoid calling memset to initialize
	a class with a default ctor.
	* gcc.c (struct compiler): Remove const qualification.
	* genattrtab.c (gen_insn_reserv): Replace memset with initialization.
	* hash-table.h: Ditto.
	* ipa-cp.c (allocate_and_init_ipcp_value): Replace memset with
	  assignment.
	* ipa-prop.c (ipa_free_edge_args_substructures): Ditto.
	* omp-low.c (lower_omp_ordered_clauses): Replace memset with
	default ctor.
	* params.h (struct param_info): Make struct members non-const.
	* tree-switch-conversion.c (emit_case_bit_tests): Replace memset
	with default initialization.
	* vec.h (vec_copy_construct, vec_default_construct): New helper
	functions.
	(vec<T>::copy, vec<T>::splice, vec<T>::reserve): Replace memcpy
	with vec_copy_construct.
	(vect<T>::quick_grow_cleared): Replace memset with default ctor.
	(vect<T>::vec_safe_grow_cleared, vec_safe_grow_cleared): Same.
	* doc/invoke.texi (-Wclass-memaccess): Document.

libcpp/ChangeLog:

	PR c++/80560
	* line-map.c (line_maps::~line_maps): Avoid calling htab_delete
	with a null pointer.
	(linemap_init): Avoid calling memset on an object of a non-trivial
	type.

libitm/ChangeLog:

	PR c++/80560
	* beginend.cc (GTM::gtm_thread::rollback): Avoid calling memset
	on an object of a non-trivial type.
	(GTM::gtm_transaction_cp::commit): Use assignment instead of memcpy
	to copy an object.
	* method-ml.cc (orec_iterator::reinit): Avoid -Wclass-memaccess.

gcc/testsuite/ChangeLog:

	PR c++/80560
	* g++.dg/Wclass-memaccess.C: New test.

From-SVN: r249234