This patch corrects an omission on the legality check of an allocator whose
expression is of a limited type, when the allocator is the expression of an
expression function.
Compiling t3.adb must yield:
t3.adb:4:13: warning: not dispatching (must be defined in a package spec)
t3.adb:5:07: initialization not allowed for limited types
---
procedure T3 is
type X_T is tagged limited null record;
type A_T is access X_T'Class;
function Clone (X : X_T) return A_T is
(new X_T'Class' (X_T'Class (X)));
X : X_T;
A : A_T := Clone (X);
begin
null;
end T3;
Tested on x86_64-pc-linux-gnu, committed on trunk
2017-10-09 Ed Schonberg <schonb...@adacore.com>
* sem_res.adb (Resolve_Allocator): Reject properly an allocator that
attempts to copy a limited value, when the allocator is the expression
in an expression function.
Index: sem_res.adb
===================================================================
--- sem_res.adb (revision 253563)
+++ sem_res.adb (working copy)
@@ -4834,10 +4834,18 @@
-- are explicitly marked as coming from source but do not need to be
-- checked for limited initialization. To exclude this case, ensure
-- that the parent of the allocator is a source node.
+ -- The return statement constructed for an Expression_Function does
+ -- not come from source but requires a limited check.
if Is_Limited_Type (Etype (E))
and then Comes_From_Source (N)
- and then Comes_From_Source (Parent (N))
+ and then
+ (Comes_From_Source (Parent (N))
+ or else
+ (Ekind (Current_Scope) = E_Function
+ and then Nkind
+ (Original_Node (Unit_Declaration_Node (Current_Scope)))
+ = N_Expression_Function))
and then not In_Instance_Body
then
if not OK_For_Limited_Init (Etype (E), Expression (E)) then
