2012-05-15  Tristan Gingold  <gingold@adacore.com>

	* a-exextr.adb: Add comment.

2012-05-15  Ed Schonberg  <schonberg@adacore.com>

	* sem_ch3.adb: Minor reformatting (remove long dead code).

2012-05-15  Ed Schonberg  <schonberg@adacore.com>

	* aspects.adb, aspects.ads: Add aspects for Convention, Export,
	External_Name, Import, and Link_Name.
	* exp_prag.adb (Expand_Pragma_Import_Or_Interface): if the
	pragma comes from an aspect specification, the entity is the
	first argument.
	* sem_prag.adb (Analyze_Pragma, cases Pragma_Export and
	Pragma_Import): if the pragma comes from an aspect specification,
	the entity is the first argument, and the second has the value
	True by default.
	* sem_ch13.adb (Analyze_Aspect_Specifications): generate pragam
	for aspect Convention. Add placeholders for Link_Name and
	External_Name.

From-SVN: r187523