This patch fixes a bug in which the compiler crashes if the number of
subcomponents in an array aggregate is 2**31 or more.
Tested on x86_64-pc-linux-gnu, committed on trunk
2017-04-25 Bob Duff <d...@adacore.com>
* exp_aggr.adb (Component_Count): Protect the
arithmetic from attempting to convert a value >= 2**31 to Int,
which would otherwise raise Constraint_Error.
Index: exp_aggr.adb
===================================================================
--- exp_aggr.adb (revision 247177)
+++ exp_aggr.adb (working copy)
@@ -352,7 +352,7 @@
-- which hit memory limits in the backend.
function Component_Count (T : Entity_Id) return Nat;
- -- The limit is applied to the total number of components that the
+ -- The limit is applied to the total number of subcomponents that the
-- aggregate will have, which is the number of static expressions
-- that will appear in the flattened array. This requires a recursive
-- computation of the number of scalar components of the structure.
@@ -399,8 +399,20 @@
return 0;
else
- return
- Siz * UI_To_Int (Expr_Value (Hi) - Expr_Value (Lo) + 1);
+ -- If the number of components is greater than Int'Last,
+ -- then return Int'Last, so caller will return False (Aggr
+ -- size is not OK). Otherwise, UI_To_Int will crash.
+
+ declare
+ UI : constant Uint :=
+ Expr_Value (Hi) - Expr_Value (Lo) + 1;
+ begin
+ if UI_Is_In_Int_Range (UI) then
+ return Siz * UI_To_Int (UI);
+ else
+ return Int'Last;
+ end if;
+ end;
end if;
end;
