-- checks, is to attempt to detect at compilation time that a constraint
-- error will occur. If this is detected a warning or error is issued and the
-- offending expression or statement replaced with a constraint error node.
--- This always occurs whether checks are suppressed or not. Dynamic range
+-- This always occurs whether checks are suppressed or not. Dynamic range
-- checks are, of course, not inserted if checks are suppressed.
with Namet; use Namet;
Typ : Entity_Id;
No_Sliding : Boolean := False);
-- Top-level procedure, calls all the others depending on the class of Typ.
- -- Checks that expression N verifies the constraint of type Typ. No_Sliding
- -- is only relevant for constrained array types, if set to True, it
- -- checks that indexes are in range.
+ -- Checks that expression N satisfies the constraint of type Typ.
+ -- No_Sliding is only relevant for constrained array types, if set to True,
+ -- it checks that indexes are in range.
procedure Apply_Discriminant_Check
(N : Node_Id;
-- Range checks are controlled by the Do_Range_Check flag. The front end
-- is responsible for setting this flag in relevant nodes. Originally
-- the back end generated all corresponding range checks. But later on
- -- we decided to generate all range checks in the front end. We are now
+ -- we decided to generate many range checks in the front end. We are now
-- in the transitional phase where some of these checks are still done
- -- by the back end, but many are done by the front end.
+ -- by the back end, but many are done by the front end. It is possible
+ -- that in the future we might move all the checks to the front end. The
+ -- main remaining back end checks are for subscript checking.
-- Overflow checks are similarly controlled by the Do_Overflow_Check flag.
-- The difference here is that if back end overflow checks are inactive
-- First this routine determines if an overflow check is needed by doing
-- an appropriate range check. If a check is not needed, then the call
-- has no effect. If a check is needed then this routine sets the flag
- -- Set Do_Overflow_Check in node N to True, unless it can be determined
- -- that the check is not needed. The only condition under which this is
- -- the case is if there was an identical check earlier on.
+ -- Do_Overflow_Check in node N to True, unless it can be determined that
+ -- the check is not needed. The only condition under which this is the
+ -- case is if there was an identical check earlier on.
procedure Enable_Range_Check (N : Node_Id);
-- Set Do_Range_Check flag in node N True, unless it can be determined
-- Some of the earlier processing for checks results in temporarily setting
-- the Do_Range_Check flag rather than actually generating checks. Now we
-- are moving the generation of such checks into the front end for reasons
- -- of efficiency and simplicity (there were difficutlies in handling this
+ -- of efficiency and simplicity (there were difficulties in handling this
-- in the back end when side effects were present in the expressions being
-- checked).
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