with Sem_Eval; use Sem_Eval;
with Sem_Intr; use Sem_Intr;
with Sem_Util; use Sem_Util;
+with Targparm; use Targparm;
with Sem_Type; use Sem_Type;
with Sem_Warn; use Sem_Warn;
with Sinfo; use Sinfo;
-- default expression mode (the Freeze_Expression routine tests this
-- flag and only freezes static types if it is set).
- Freeze_Expression (N);
+ -- AI05-177 (Ada2012): Expression functions do not freeze. Only
+ -- their use (in an expanded call) freezes.
+
+ if Ekind (Current_Scope) /= E_Function
+ or else
+ Nkind (Original_Node (Unit_Declaration_Node (Current_Scope))) /=
+ N_Expression_Function
+ then
+ Freeze_Expression (N);
+ end if;
-- Now we can do the expansion
(Is_Real_Type (Etype (Rop))
and then Expr_Value_R (Rop) = Ureal_0))
then
- -- Specialize the warning message according to the operation
+ -- Specialize the warning message according to the operation.
+ -- The following warnings are for the case
case Nkind (N) is
when N_Op_Divide =>
- Apply_Compile_Time_Constraint_Error
- (N, "division by zero?", CE_Divide_By_Zero,
- Loc => Sloc (Right_Opnd (N)));
+
+ -- For division, we have two cases, for float division
+ -- of an unconstrained float type, on a machine where
+ -- Machine_Overflows is false, we don't get an exception
+ -- at run-time, but rather an infinity or Nan. The Nan
+ -- case is pretty obscure, so just warn about infinities.
+
+ if Is_Floating_Point_Type (Typ)
+ and then not Is_Constrained (Typ)
+ and then not Machine_Overflows_On_Target
+ then
+ Error_Msg_N
+ ("float division by zero, " &
+ "may generate '+'/'- infinity?", Right_Opnd (N));
+
+ -- For all other cases, we get a Constraint_Error
+
+ else
+ Apply_Compile_Time_Constraint_Error
+ (N, "division by zero?", CE_Divide_By_Zero,
+ Loc => Sloc (Right_Opnd (N)));
+ end if;
when N_Op_Rem =>
Apply_Compile_Time_Constraint_Error
return Res;
end Convert_Operand;
- -- Start of processing for Resolve_Intrinsic_Operator
+ -- Start of processing for Resolve_Intrinsic_Operator
begin
-- We must preserve the original entity in a generic setting, so that
then
Arg1 := Convert_Operand (Left_Opnd (N));
-- Unchecked_Convert_To (Btyp, Left_Opnd (N));
+ -- What on earth is this commented out fragment of code???
if Nkind (N) = N_Op_Expon then
Arg2 := Unchecked_Convert_To (Standard_Integer, Right_Opnd (N));
Check_For_Visible_Operator (N, B_Typ);
end if;
+ -- Replace AND by AND THEN, or OR by OR ELSE, if Short_Circuit_And_Or
+ -- is active and the result type is standard Boolean (do not mess with
+ -- ops that return a nonstandard Boolean type, because something strange
+ -- is going on).
+
+ -- Note: you might expect this replacement to be done during expansion,
+ -- but that doesn't work, because when the pragma Short_Circuit_And_Or
+ -- is used, no part of the right operand of an "and" or "or" operator
+ -- should be executed if the left operand would short-circuit the
+ -- evaluation of the corresponding "and then" or "or else". If we left
+ -- the replacement to expansion time, then run-time checks associated
+ -- with such operands would be evaluated unconditionally, due to being
+ -- before the condition prior to the rewriting as short-circuit forms
+ -- during expansion.
+
+ if Short_Circuit_And_Or
+ and then B_Typ = Standard_Boolean
+ and then Nkind_In (N, N_Op_And, N_Op_Or)
+ then
+ if Nkind (N) = N_Op_And then
+ Rewrite (N,
+ Make_And_Then (Sloc (N),
+ Left_Opnd => Relocate_Node (Left_Opnd (N)),
+ Right_Opnd => Relocate_Node (Right_Opnd (N))));
+ Analyze_And_Resolve (N, B_Typ);
+
+ -- Case of OR changed to OR ELSE
+
+ else
+ Rewrite (N,
+ Make_Or_Else (Sloc (N),
+ Left_Opnd => Relocate_Node (Left_Opnd (N)),
+ Right_Opnd => Relocate_Node (Right_Opnd (N))));
+ Analyze_And_Resolve (N, B_Typ);
+ end if;
+
+ -- Return now, since analysis of the rewritten ops will take care of
+ -- other reference bookkeeping and expression folding.
+
+ return;
+ end if;
+
Resolve (Left_Opnd (N), B_Typ);
Resolve (Right_Opnd (N), B_Typ);
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