d: Merge upstream dmd 568496d5b, druntime 178c44ff, phobos 574bf883b.

d: Merge upstream dmd 568496d5b, druntime 178c44ff, phobos 574bf883b.

D front-end changes:

    - Import dmd v2.098.0
    - New ImportC module for compiling preprocessed C11 code into D.
    - New -ftransition=in switch.
    - Improved handling of new 'noreturn' type.

Druntime changes:

    - Import druntime v2.098.0
    - Fix broken import in core.sys.linux.perf_event module (PR103558).

Phobos changes:

    - Import phobos v2.098.0
    - All sources are now compiled with -fpreview=fieldwise.

gcc/d/ChangeLog:

	* dmd/MERGE: Merge upstream dmd 568496d5b.
	* Make-lang.in (D_FRONTEND_OBJS): Add d/common-file.o,
	d/common-outbuffer.o, d/common-string.o, d/file_manager.o,
	d/importc.o.  Remove d/root-outbuffer.o.
	(d/common-%.o): New recipe.
	* d-builtins.cc (build_frontend_type): Update for new front-end
	interface.
	(d_build_d_type_nodes): Set noreturn_type_node.
	* d-codegen.cc (d_build_call): Don't call function if one of the
	arguments is type 'noreturn'.
	(build_vthis_function): Propagate TYPE_QUAL_VOLATILE from original
	function type.
	* d-frontend.cc (eval_builtin): Update signature.
	(getTypeInfoType): Likewise.
	(toObjFile): New function.
	* d-gimplify.cc (d_gimplify_call_expr): Always evaluate arguments from
	left to right.
	* d-lang.cc (d_handle_option): Handle OPT_ftransition_in.
	(d_parse_file): Don't generate D main if it is declared in user code.
	* d-tree.h (CALL_EXPR_ARGS_ORDERED): Remove.
	(enum d_tree_index): Add DTI_BOTTOM_TYPE.
	(noreturn_type_node): New.
	* decl.cc (apply_pragma_crt): Remove.
	(DeclVisitor::visit): Update for new front-end interface.
	(DeclVisitor::visit (PragmaDeclaration *)): Don't handle
	crt_constructor and crt_destructor pragmas.
	(DeclVisitor::visit (VarDeclaration *)): Don't generate declarations
	of type 'noreturn'.
	(DeclVisitor::visit (FuncDeclaration *)): Stop adding parameters when
	'noreturn' type has been encountered.
	(get_symbol_decl): Set DECL_STATIC_CONSTRUCTOR and
	DECL_STATIC_DESTRUCTOR on decl node if requested.
	(aggregate_initializer_decl): Update for new front-end interface.
	* expr.cc (ExprVisitor::visit (CallExp *)): Always use the 'this'
	object as the result of calling any constructor function.
	(ExprVisitor::visit): Update for new front-end interface.
	* gdc.texi (Runtime Options): Document -fmain and -ftransition=in.
	* lang.opt (ftransition=in): New option.
	* modules.cc (get_internal_fn): Update for new front-end interface.
	* types.cc (TypeVisitor::visit): Likewise.
	(TypeVisitor::visit (TypeNoreturn *)): Return noreturn_type_node.
	(TypeVisitor::visit (TypeFunction *)): Stop adding parameters when
	'notreturn' type has been encountered.  Qualify function types that
	return 'noreturn' as TYPE_QUAL_VOLATILE.

libphobos/ChangeLog:

	PR d/103558
	* libdruntime/MERGE: Merge upstream druntime 178c44ff.
	* libdruntime/Makefile.am (DRUNTIME_DSOURCES_LINUX): Add
	core/sys/linux/syscalls.d.
	(DRUNTIME_DSOURCES_OPENBSD): Add core/sys/openbsd/pthread_np.d.
	* libdruntime/Makefile.in: Regenerate.
	* src/MERGE: Merge upstream phobos 574bf883b.
	* src/Makefile.am (D_EXTRA_DFLAGS): Add -fpreview=fieldwise.
	* src/Makefile.in: Regenerate.
	* testsuite/libphobos.exceptions/assert_fail.d: Update test.
	* testsuite/libphobos.betterc/test22336.d: New test.