with Atree; use Atree;
with Checks; use Checks;
with Einfo; use Einfo;
with Errout; use Errout;
with Lib; use Lib;
with Lib.Xref; use Lib.Xref;
with Nlists; use Nlists;
with Nmake; use Nmake;
with Opt; use Opt;
with Restrict; use Restrict;
with Rident; use Rident;
with Rtsfind; use Rtsfind;
with Sem; use Sem;
with Sem_Ch5; use Sem_Ch5;
with Sem_Ch8; use Sem_Ch8;
with Sem_Res; use Sem_Res;
with Sem_Util; use Sem_Util;
with Sinfo; use Sinfo;
with Stand; use Stand;
with Uintp; use Uintp;
package body Sem_Ch11 is
procedure Analyze_Exception_Declaration (N : Node_Id) is
Id : constant Entity_Id := Defining_Identifier (N);
PF : constant Boolean := Is_Pure (Current_Scope);
begin
Generate_Definition (Id);
Enter_Name (Id);
Set_Ekind (Id, E_Exception);
Set_Exception_Code (Id, Uint_0);
Set_Etype (Id, Standard_Exception_Type);
Set_Is_Statically_Allocated (Id);
Set_Is_Pure (Id, PF);
end Analyze_Exception_Declaration;
procedure Analyze_Exception_Handlers (L : List_Id) is
Handler : Node_Id;
Choice : Entity_Id;
Id : Node_Id;
H_Scope : Entity_Id := Empty;
procedure Check_Duplication (Id : Node_Id);
function Others_Present return Boolean;
procedure Check_Duplication (Id : Node_Id) is
Handler : Node_Id;
Id1 : Node_Id;
Id_Entity : Entity_Id := Entity (Id);
begin
if Present (Renamed_Entity (Id_Entity)) then
Id_Entity := Renamed_Entity (Id_Entity);
end if;
Handler := First_Non_Pragma (L);
while Present (Handler) loop
Id1 := First (Exception_Choices (Handler));
while Present (Id1) loop
if Id = Id1 then
return;
elsif Nkind (Id1) /= N_Others_Choice
and then
(Id_Entity = Entity (Id1)
or else (Id_Entity = Renamed_Entity (Entity (Id1))))
then
if Handler /= Parent (Id) then
Error_Msg_Sloc := Sloc (Id1);
Error_Msg_NE
("exception choice duplicates &#", Id, Id1);
else
if Ada_Version = Ada_83
and then Comes_From_Source (Id)
then
Error_Msg_N
("(Ada 83): duplicate exception choice&", Id);
end if;
end if;
end if;
Next_Non_Pragma (Id1);
end loop;
Next (Handler);
end loop;
end Check_Duplication;
function Others_Present return Boolean is
H : Node_Id;
begin
H := First (L);
while Present (H) loop
if Nkind (H) /= N_Pragma
and then Nkind (First (Exception_Choices (H))) = N_Others_Choice
then
return True;
end if;
Next (H);
end loop;
return False;
end Others_Present;
begin
Handler := First (L);
Check_Restriction (No_Exceptions, Handler);
Check_Restriction (No_Exception_Handlers, Handler);
Kill_Current_Values;
while Present (Handler) loop
if Nkind (Handler) = N_Pragma then
Analyze (Handler);
else
Choice := Choice_Parameter (Handler);
if Present (Choice) then
if No (H_Scope) then
H_Scope := New_Internal_Entity
(E_Block, Current_Scope, Sloc (Choice), 'E');
end if;
New_Scope (H_Scope);
Set_Etype (H_Scope, Standard_Void_Type);
Set_Finalization_Chain_Entity (H_Scope, Error);
Enter_Name (Choice);
Set_Ekind (Choice, E_Variable);
Set_Etype (Choice, RTE (RE_Exception_Occurrence));
Generate_Definition (Choice);
Set_Never_Set_In_Source (Choice, False);
end if;
Id := First (Exception_Choices (Handler));
while Present (Id) loop
if Nkind (Id) = N_Others_Choice then
if Present (Next (Id))
or else Present (Next (Handler))
or else Present (Prev (Id))
then
Error_Msg_N ("OTHERS must appear alone and last", Id);
end if;
else
Analyze (Id);
if not Is_Entity_Name (Id)
or else Ekind (Entity (Id)) /= E_Exception
then
Error_Msg_N ("exception name expected", Id);
else
if Present (Renamed_Entity (Entity (Id))) then
if Entity (Id) = Standard_Numeric_Error then
Check_Restriction (No_Obsolescent_Features, Id);
if Warn_On_Obsolescent_Feature then
Error_Msg_N
("Numeric_Error is an " &
"obsolescent feature ('R'M 'J.6(1))?", Id);
Error_Msg_N
("\use Constraint_Error instead?", Id);
end if;
end if;
end if;
Check_Duplication (Id);
declare
Ent : Entity_Id := Entity (Id);
Scop : Entity_Id;
begin
if Present (Renamed_Entity (Ent)) then
Ent := Renamed_Entity (Ent);
end if;
Scop := Scope (Ent);
while Scop /= Standard_Standard
and then Ekind (Scop) = E_Package
loop
if Is_Generic_Instance (Scop) then
exit;
elsif Nkind (Declaration_Node (Scop)) =
N_Package_Specification
and then
Nkind (Original_Node (Parent
(Declaration_Node (Scop)))) =
N_Formal_Package_Declaration
then
Error_Msg_NE
("exception& is declared in " &
"generic formal package", Id, Ent);
Error_Msg_N
("\and therefore cannot appear in " &
"handler ('R'M 11.2(8))", Id);
exit;
end if;
Scop := Scope (Scop);
end loop;
end;
end if;
end if;
Next (Id);
end loop;
if Warn_On_Redundant_Constructs
and then List_Length (Statements (Handler)) = 1
and then Nkind (First (Statements (Handler))) = N_Raise_Statement
and then No (Name (First (Statements (Handler))))
and then (not Others_Present
or else Nkind (First (Exception_Choices (Handler))) =
N_Others_Choice)
then
Error_Msg_N
("useless handler contains only a reraise statement?",
Handler);
end if;
Analyze_Statements (Statements (Handler));
if Present (Choice) then
End_Scope;
end if;
end if;
Next (Handler);
end loop;
end Analyze_Exception_Handlers;
procedure Analyze_Handled_Statements (N : Node_Id) is
Handlers : constant List_Id := Exception_Handlers (N);
begin
if Present (Handlers) then
Kill_All_Checks;
end if;
Analyze_Statements (Statements (N));
if Present (Handlers) then
Analyze_Exception_Handlers (Handlers);
elsif Present (At_End_Proc (N)) then
Analyze (At_End_Proc (N));
end if;
end Analyze_Handled_Statements;
procedure Analyze_Raise_Statement (N : Node_Id) is
Exception_Id : constant Node_Id := Name (N);
Exception_Name : Entity_Id := Empty;
P : Node_Id;
Nkind_P : Node_Kind;
begin
Check_Unreachable_Code (N);
if Comes_From_Source (N) then
Check_Restriction (No_Exceptions, N);
end if;
if Is_List_Member (N) then
declare
P : Node_Id;
L : Node_Id;
begin
P := Prev (N);
if Present (P)
and then Nkind (P) = N_Assignment_Statement
then
L := Name (P);
if Is_Scalar_Type (Etype (L))
and then Is_Entity_Name (L)
and then Is_Formal (Entity (L))
then
Error_Msg_N
("?assignment to pass-by-copy formal may have no effect",
P);
Error_Msg_N
("\?RAISE statement is abnormal return" &
" ('R'M 6.4.1(17))", P);
end if;
end if;
end;
end if;
if No (Exception_Id) then
P := Parent (N);
Nkind_P := Nkind (P);
while Nkind_P /= N_Exception_Handler
and then Nkind_P /= N_Subprogram_Body
and then Nkind_P /= N_Package_Body
and then Nkind_P /= N_Task_Body
and then Nkind_P /= N_Entry_Body
loop
P := Parent (P);
Nkind_P := Nkind (P);
end loop;
if Nkind (P) /= N_Exception_Handler then
Error_Msg_N
("reraise statement must appear directly in a handler", N);
end if;
else
Analyze (Exception_Id);
if Is_Entity_Name (Exception_Id) then
Exception_Name := Entity (Exception_Id);
end if;
if No (Exception_Name)
or else Ekind (Exception_Name) /= E_Exception
then
Error_Msg_N
("exception name expected in raise statement", Exception_Id);
end if;
end if;
end Analyze_Raise_Statement;
procedure Analyze_Raise_xxx_Error (N : Node_Id) is
begin
if No (Etype (N)) then
Set_Etype (N, Standard_Void_Type);
end if;
if Present (Condition (N)) then
Analyze_And_Resolve (Condition (N), Standard_Boolean);
end if;
if Nkind (Condition (N)) = N_Identifier then
if Entity (Condition (N)) = Standard_True then
Set_Condition (N, Empty);
elsif Entity (Condition (N)) = Standard_False then
Rewrite (N, Make_Null_Statement (Sloc (N)));
end if;
end if;
end Analyze_Raise_xxx_Error;
procedure Analyze_Subprogram_Info (N : Node_Id) is
begin
Set_Etype (N, RTE (RE_Code_Loc));
end Analyze_Subprogram_Info;
end Sem_Ch11;