This patch suppresses elaboration checks on stack-related finalizers. Both the
spec and body of a finalizer are within the same construct and scope, but the
body is part of the handled sequence of statements. This placement confuses the
elaboration mechanism on targets which do not fully support AT_END handlers.
Since the compiler guarantees that the body of a finalizer is always inserted
in the same construct where the AT_END handler resides, there is no need for
elaboration checks.
Tested on x86_64-pc-linux-gnu, committed on trunk
2012-02-22 Hristian Kirtchev <kirtc...@adacore.com>
* exp_ch7.adb (Create_Finalizer): Suppress elaboration checks on
stack-related finalizers.
Index: exp_ch7.adb
===================================================================
--- exp_ch7.adb (revision 184470)
+++ exp_ch7.adb (working copy)
@@ -1372,6 +1372,37 @@
Fin_Id :=
Make_Defining_Identifier (Loc,
Chars => New_External_Name (Name_uFinalizer));
+
+ -- The visibility semantics of AT_END handlers force a strange
+ -- separation of spec and body for stack-related finalizers:
+
+ -- declare : Enclosing_Scope
+ -- procedure _finalizer;
+ -- begin
+ -- <controlled objects>
+ -- procedure _finalizer is
+ -- ...
+ -- at end
+ -- _finalizer;
+ -- end;
+
+ -- Both spec and body are within the same construct and scope, but
+ -- the body is part of the handled sequence of statements. This
+ -- placement confuses the elaboration mechanism on targets where
+ -- AT_END handlers are expanded into "when all others" handlers:
+
+ -- exception
+ -- when all others =>
+ -- _finalizer; -- appears to require elab checks
+ -- at end
+ -- _finalizer;
+ -- end;
+
+ -- Since the compiler guarantees that the body of a _finalizer is
+ -- always inserted in the same construct where the AT_END handler
+ -- resides, there is no need for elaboration checks.
+
+ Set_Kill_Elaboration_Checks (Fin_Id);
end if;
-- Step 2: Creation of the finalizer specification
