re PR c++/35368 (With #pragma visibility, `vtable for __cxxabiv1::__class_type_info' is emitted as a hidden-visibility relocation)

	PR c++/35368
	* rtti.c: Include c-pragma.h.
	(push_abi_namespace, pop_abi_namespace): New functions.
	(build_dynamic_cast_1, tinfo_base_init, get_pseudo_ti_index,
	create_tinfo_types, emit_support_tinfos): Use them.
	* Make-lang.in (cp/rtti.o): Depend on $(C_PRAGMA_H).

	* g++.dg/ext/visibility/typeinfo2.C: New test.
	* g++.dg/ext/visibility/typeinfo3.C: New test.

From-SVN: r132704