CVS difference for ais/ai-00421.txt
--- ais/ai-00421.txt 2005/05/06 01:43:40 1.2
+++ ais/ai-00421.txt 2005/05/06 01:49:49 1.3
@@ -1,4 +1,4 @@
-!standard H.06(01) 05-04-17 AI95-00421/02
+!standard H.06(01) 05-04-18 AI95-00421/03
!class amendment 05-03-28
!status work item
@@ -26,32 +26,40 @@
Replace the second and third paragraphs of the dynamic semantics section of
H.6 (as defined by AI-265) with
-If the partition elaboration policy is Sequential, all task activations
-for library-level tasks and all interrupt handler attachments for
-library-level interrupt handlers are deferred. The handler attachments
-occur after the elaboration of all library_items. Then the
-Environment task is suspended and all deferred activations are
-completed. The Environment task then calls the main program.
+If the partition elaboration policy is Sequential, then task
+activation and interrupt attachment are performed in the following sequence
+ * The activation of all library level tasks and the attachment of
+ interrupt handlers are deferred until all library units are elaborated.
+ * The interrupt handlers are then attached by the environment task.
+ * The environment task is then suspended while the library tasks are
+ * The environment task then executes the main subprogram (if any)
+ concurrently with these executing tasks.
If any deferred task activation fails, Tasking_Error is raised in the
-Environment task at the beginning of the sequence of statements
-of the main program. If a number of dynamic interrupt handler
-attachments for the same interrupt are deferred then the most
-recent call of Attach_Handler or Exchange_Handler determines which
-handler is attached.
+environment task at the beginning of the sequence of statements of the
+body of the environment task prior to calling the
+main subprogram. If several dynamic interrupt handler attachments for
+the same interrrupt are deferred then the most recent call of
+Attach_Handler or Exchange_Handler determines which handler is attached.
Add a new Note:
-If any task activation fails the Environment task is unable
-to handle Tasking_Error and will become completed immediately.
-With the standard partition elaboration policy this exception
+If any task activation fails, the environment task is unable to handle
+the Tasking_Error exception and completes immediately. By contrast, if
+the partition elaboration policy is Concurrent, then this exception
could be handled within a library unit.
-The essence of AI-265 was OK, just a bit vague. It is now clear that the
-sequential order is: library items, handler attachments, library task
-activations, main program.
+The essence of AI-265 was OK, just a bit vague. It is now clear that
+the sequential order is: library item elaboration, handler attachments,
+library task activations, call of main subprogram.
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