CVS difference for ai12s/ai12-0279-1.txt

Differences between 1.2 and version 1.3
Log of other versions for file ai12s/ai12-0279-1.txt

--- ai12s/ai12-0279-1.txt	2018/05/18 01:58:47	1.2
+++ ai12s/ai12-0279-1.txt	2018/06/12 05:28:47	1.3
@@ -408,3 +408,52 @@
 
 ****************************************************************
 
+From: Erhard Ploedereder
+Sent: Sunday, May 20, 2018  5:49 PM
+
+The AI says:
+> All potentially blocking operations are preemption points for the 
+> Non-Preemptive Dispatching Policy
+
+The RM says:
+> The following are defined to be potentially blocking operations:
+>  ... << good stuff>>
+>  a call on a subprogram whose body contains a potentially blocking 
+>   operation.
+
+So, the rules combine to make every call site down the stack towards the
+really potentially blocking operation a dispatching point.
+
+I don't think that anybody wants that to happen.
+
+****************************************************************
+
+From: Randy Brukardt
+Sent: Thursday, May 31, 2018  10:03 PM
+
+> The RM says:
+> > The following are defined to be potentially blocking operations:
+> >  ... << good stuff>>
+> > . a call on a subprogram whose body contains a potentially
+> blocking operation.
+
+No, it doesn't. At least not the draft Ada 2020 RM, which is the one that
+matters here!
+
+More specifically, AI12-0249-1 removed that line and made it into a separate
+rule because it messed up Detect_Blocking (see the AI for details). We
+discussed and approved that during the January meeting. So you have to be
+using the April version of the draft RM (the HTML version, since there is no
+April PDF version) in order to see that.
+
+> So, the rules combine to make every call site down the stack 
+> towards the really potentially blocking operation a dispatching point.
+
+As noted above, they don't.
+ 
+> I don't think that anybody wants that to happen.
+
+And it doesn't.
+
+****************************************************************
+

Questions? Ask the ACAA Technical Agent