[Ada] ada05 optimization in handling of non-null access parameters

[Arnaud Charlet <charlet at adacore dot com>]

Tested on i686-linux, committed on HEAD

This is an optimization afforded by an Ada2005 feature: subtypes that
carry a "not null" indication. In Ada95 only access parameters are
specified to be non-null.
Part of the ongoing activity to implement Ada2005 in full.

2005-03-29  Ed Schonberg  <schonberg@adacore.com>

	* sem_ch6.adb (Set_Formal_Mode): If the subtype has a non_null
	indicator, indicate that the formal can never be null.
	(Process_Formals): If a formal has a non_null indicator, insert the
	resulting subtype immediately before the enclosing subprogram decl,
	and not at the beginning of the corresponding declarative part, to
	prevent access before elaboration (Ada2005).

Attachment: difs.21
Description: Text document