gdb/

gdb/
	Fix lost siginfo_t for inferior calls.
	* infrun.c
	(struct inferior_thread_state) <siginfo_gdbarch, siginfo_data>: New.
	(save_inferior_thread_state): New variables regcache, gdbarch and
	siginfo_data.  Initialize SIGINFO_DATA if gdbarch_get_siginfo_type_p.
	Move INF_STATE allocation later, pre-clear it.  Initialize REGISTERS
	using REGCACHE.
	(restore_inferior_thread_state): New variables regcache and gdbarch.
	Restore SIGINFO_DATA for matching GDBARCH.  Restore REGISTERS using
	REGCACHE.  Free also SIGINFO_DATA.

gdb/testsuite/
	Fix lost siginfo_t for inferior calls.
	* gdb.base/siginfo-infcall.exp: New file.
	* gdb.base/siginfo-infcall.c: New file.