From: Piotr Trojanek <troja...@adacore.com>
Listing an object as a state refinement constituent shouldn't be
considered to be a reference, at least from the point of view of the
machinery for detecting objects that are never referenced or written
without being referenced.
This patch fixes a spurious warning that rarely occurred in practice but
was annoyingly emitted for minimal reproducers for issues related to
state abstractions.
Note: there are other pragmas that should be similarly recognized (e.g.
Depends, Global and their refined variants), but recognizing them
efficiently probably requires a dedicated utility routine (i.e. to avoid
traversal of the parent chain for every kind of pragma).
gcc/ada/
* sem_prag.adb
(Sig_Pragma): Change flag for pragma Refined_State to mean "not
significant"; this is primarily for documentation, because the
exact value of the flag is not really taken into account for
Refined_State.
(Is_Non_Significant_Pragma_Reference): Add special handling for
pragma Refined_State.
Tested on x86_64-pc-linux-gnu, committed on master.
---
gcc/ada/sem_prag.adb | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/gcc/ada/sem_prag.adb b/gcc/ada/sem_prag.adb
index 77ff68e23cb..0c3dd815263 100644
--- a/gcc/ada/sem_prag.adb
+++ b/gcc/ada/sem_prag.adb
@@ -31608,7 +31608,7 @@ package body Sem_Prag is
Pragma_Refined_Depends => -1,
Pragma_Refined_Global => -1,
Pragma_Refined_Post => -1,
- Pragma_Refined_State => -1,
+ Pragma_Refined_State => 0,
Pragma_Relative_Deadline => 0,
Pragma_Remote_Access_Type => -1,
Pragma_Remote_Call_Interface => -1,
@@ -31713,6 +31713,15 @@ package body Sem_Prag is
P := Parent (N);
if Nkind (P) /= N_Pragma_Argument_Association then
+
+ -- References within pragma Refined_State are not significant. They
+ -- can't be recognized using pragma argument number, because they
+ -- appear inside refinement clauses that rely on aggregate syntax.
+
+ if In_Pragma_Expression (N, Name_Refined_State) then
+ return True;
+ end if;
+
return False;
else
--
2.34.1
