------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- S E M _ C H 1 3 -- -- -- -- B o d y -- -- -- -- Copyright (C) 1992-2016, Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 3, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- -- for more details. You should have received a copy of the GNU General -- -- Public License distributed with GNAT; see file COPYING3. If not, go to -- -- http://www.gnu.org/licenses for a complete copy of the license. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ with Aspects; use Aspects; with Atree; use Atree; with Checks; use Checks; with Debug; use Debug; with Einfo; use Einfo; with Elists; use Elists; with Errout; use Errout; with Exp_Disp; use Exp_Disp; with Exp_Tss; use Exp_Tss; with Exp_Util; use Exp_Util; with Freeze; use Freeze; with Ghost; use Ghost; with Lib; use Lib; with Lib.Xref; use Lib.Xref; with Namet; use Namet; 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_Aux; use Sem_Aux; with Sem_Case; use Sem_Case; with Sem_Ch3; use Sem_Ch3; with Sem_Ch6; use Sem_Ch6; with Sem_Ch8; use Sem_Ch8; with Sem_Dim; use Sem_Dim; with Sem_Disp; use Sem_Disp; with Sem_Eval; use Sem_Eval; with Sem_Prag; use Sem_Prag; with Sem_Res; use Sem_Res; with Sem_Type; use Sem_Type; with Sem_Util; use Sem_Util; with Sem_Warn; use Sem_Warn; with Sinput; use Sinput; with Snames; use Snames; with Stand; use Stand; with Sinfo; use Sinfo; with Targparm; use Targparm; with Ttypes; use Ttypes; with Tbuild; use Tbuild; with Urealp; use Urealp; with Warnsw; use Warnsw; with GNAT.Heap_Sort_G; package body Sem_Ch13 is SSU : constant Pos := System_Storage_Unit; -- Convenient short hand for commonly used constant ----------------------- -- Local Subprograms -- ----------------------- procedure Alignment_Check_For_Size_Change (Typ : Entity_Id; Size : Uint); -- This routine is called after setting one of the sizes of type entity -- Typ to Size. The purpose is to deal with the situation of a derived -- type whose inherited alignment is no longer appropriate for the new -- size value. In this case, we reset the Alignment to unknown. procedure Build_Discrete_Static_Predicate (Typ : Entity_Id; Expr : Node_Id; Nam : Name_Id); -- Given a predicated type Typ, where Typ is a discrete static subtype, -- whose predicate expression is Expr, tests if Expr is a static predicate, -- and if so, builds the predicate range list. Nam is the name of the one -- argument to the predicate function. Occurrences of the type name in the -- predicate expression have been replaced by identifier references to this -- name, which is unique, so any identifier with Chars matching Nam must be -- a reference to the type. If the predicate is non-static, this procedure -- returns doing nothing. If the predicate is static, then the predicate -- list is stored in Static_Discrete_Predicate (Typ), and the Expr is -- rewritten as a canonicalized membership operation. function Build_Export_Import_Pragma (Asp : Node_Id; Id : Entity_Id) return Node_Id; -- Create the corresponding pragma for aspect Export or Import denoted by -- Asp. Id is the related entity subject to the aspect. Return Empty when -- the expression of aspect Asp evaluates to False or is erroneous. function Build_Predicate_Function_Declaration (Typ : Entity_Id) return Node_Id; -- Build the declaration for a predicate function. The declaration is built -- at the end of the declarative part containing the type definition, which -- may be before the freeze point of the type. The predicate expression is -- pre-analyzed at this point, to catch visibility errors. procedure Build_Predicate_Functions (Typ : Entity_Id; N : Node_Id); -- If Typ has predicates (indicated by Has_Predicates being set for Typ), -- then either there are pragma Predicate entries on the rep chain for the -- type (note that Predicate aspects are converted to pragma Predicate), or -- there are inherited aspects from a parent type, or ancestor subtypes. -- This procedure builds body for the Predicate function that tests these -- predicates. N is the freeze node for the type. The spec of the function -- is inserted before the freeze node, and the body of the function is -- inserted after the freeze node. If the predicate expression has a least -- one Raise_Expression, then this procedure also builds the M version of -- the predicate function for use in membership tests. procedure Check_Pool_Size_Clash (Ent : Entity_Id; SP, SS : Node_Id); -- Called if both Storage_Pool and Storage_Size attribute definition -- clauses (SP and SS) are present for entity Ent. Issue error message. procedure Freeze_Entity_Checks (N : Node_Id); -- Called from Analyze_Freeze_Entity and Analyze_Generic_Freeze Entity -- to generate appropriate semantic checks that are delayed until this -- point (they had to be delayed this long for cases of delayed aspects, -- e.g. analysis of statically predicated subtypes in choices, for which -- we have to be sure the subtypes in question are frozen before checking). function Get_Alignment_Value (Expr : Node_Id) return Uint; -- Given the expression for an alignment value, returns the corresponding -- Uint value. If the value is inappropriate, then error messages are -- posted as required, and a value of No_Uint is returned. procedure Get_Interfacing_Aspects (Iface_Asp : Node_Id; Conv_Asp : out Node_Id; EN_Asp : out Node_Id; Expo_Asp : out Node_Id; Imp_Asp : out Node_Id; LN_Asp : out Node_Id; Do_Checks : Boolean := False); -- Given a single interfacing aspect Iface_Asp, retrieve other interfacing -- aspects that apply to the same related entity. The aspects considered by -- this routine are as follows: -- -- Conv_Asp - aspect Convention -- EN_Asp - aspect External_Name -- Expo_Asp - aspect Export -- Imp_Asp - aspect Import -- LN_Asp - aspect Link_Name -- -- When flag Do_Checks is set, this routine will flag duplicate uses of -- aspects. function Is_Operational_Item (N : Node_Id) return Boolean; -- A specification for a stream attribute is allowed before the full type -- is declared, as explained in AI-00137 and the corrigendum. Attributes -- that do not specify a representation characteristic are operational -- attributes. function Is_Predicate_Static (Expr : Node_Id; Nam : Name_Id) return Boolean; -- Given predicate expression Expr, tests if Expr is predicate-static in -- the sense of the rules in (RM 3.2.4 (15-24)). Occurrences of the type -- name in the predicate expression have been replaced by references to -- an identifier whose Chars field is Nam. This name is unique, so any -- identifier with Chars matching Nam must be a reference to the type. -- Returns True if the expression is predicate-static and False otherwise, -- but is not in the business of setting flags or issuing error messages. -- -- Only scalar types can have static predicates, so False is always -- returned for non-scalar types. -- -- Note: the RM seems to suggest that string types can also have static -- predicates. But that really makes lttle sense as very few useful -- predicates can be constructed for strings. Remember that: -- -- "ABC" < "DEF" -- -- is not a static expression. So even though the clearly faulty RM wording -- allows the following: -- -- subtype S is String with Static_Predicate => S < "DEF" -- -- We can't allow this, otherwise we have predicate-static applying to a -- larger class than static expressions, which was never intended. procedure New_Stream_Subprogram (N : Node_Id; Ent : Entity_Id; Subp : Entity_Id; Nam : TSS_Name_Type); -- Create a subprogram renaming of a given stream attribute to the -- designated subprogram and then in the tagged case, provide this as a -- primitive operation, or in the untagged case make an appropriate TSS -- entry. This is more properly an expansion activity than just semantics, -- but the presence of user-defined stream functions for limited types -- is a legality check, which is why this takes place here rather than in -- exp_ch13, where it was previously. Nam indicates the name of the TSS -- function to be generated. -- -- To avoid elaboration anomalies with freeze nodes, for untagged types -- we generate both a subprogram declaration and a subprogram renaming -- declaration, so that the attribute specification is handled as a -- renaming_as_body. For tagged types, the specification is one of the -- primitive specs. procedure Resolve_Iterable_Operation (N : Node_Id; Cursor : Entity_Id; Typ : Entity_Id; Nam : Name_Id); -- If the name of a primitive operation for an Iterable aspect is -- overloaded, resolve according to required signature. procedure Set_Biased (E : Entity_Id; N : Node_Id; Msg : String; Biased : Boolean := True); -- If Biased is True, sets Has_Biased_Representation flag for E, and -- outputs a warning message at node N if Warn_On_Biased_Representation is -- is True. This warning inserts the string Msg to describe the construct -- causing biasing. ---------------------------------------------- -- Table for Validate_Unchecked_Conversions -- ---------------------------------------------- -- The following table collects unchecked conversions for validation. -- Entries are made by Validate_Unchecked_Conversion and then the call -- to Validate_Unchecked_Conversions does the actual error checking and -- posting of warnings. The reason for this delayed processing is to take -- advantage of back-annotations of size and alignment values performed by -- the back end. -- Note: the reason we store a Source_Ptr value instead of a Node_Id is -- that by the time Validate_Unchecked_Conversions is called, Sprint will -- already have modified all Sloc values if the -gnatD option is set. type UC_Entry is record Eloc : Source_Ptr; -- node used for posting warnings Source : Entity_Id; -- source type for unchecked conversion Target : Entity_Id; -- target type for unchecked conversion Act_Unit : Entity_Id; -- actual function instantiated end record; package Unchecked_Conversions is new Table.Table ( Table_Component_Type => UC_Entry, Table_Index_Type => Int, Table_Low_Bound => 1, Table_Initial => 50, Table_Increment => 200, Table_Name => "Unchecked_Conversions"); ---------------------------------------- -- Table for Validate_Address_Clauses -- ---------------------------------------- -- If an address clause has the form -- for X'Address use Expr -- where Expr has a value known at compile time or is of the form Y'Address -- or recursively is a reference to a constant initialized with either of -- these forms, and the value of Expr is not a multiple of X's alignment, -- or if Y has a smaller alignment than X, then that merits a warning about -- possible bad alignment. The following table collects address clauses of -- this kind. We put these in a table so that they can be checked after the -- back end has completed annotation of the alignments of objects, since we -- can catch more cases that way. type Address_Clause_Check_Record is record N : Node_Id; -- The address clause X : Entity_Id; -- The entity of the object subject to the address clause A : Uint; -- The value of the address in the first case Y : Entity_Id; -- The entity of the object being overlaid in the second case Off : Boolean; -- Whether the address is offset within Y in the second case end record; package Address_Clause_Checks is new Table.Table ( Table_Component_Type => Address_Clause_Check_Record, Table_Index_Type => Int, Table_Low_Bound => 1, Table_Initial => 20, Table_Increment => 200, Table_Name => "Address_Clause_Checks"); ----------------------------------------- -- Adjust_Record_For_Reverse_Bit_Order -- ----------------------------------------- procedure Adjust_Record_For_Reverse_Bit_Order (R : Entity_Id) is Comp : Node_Id; CC : Node_Id; begin -- Processing depends on version of Ada -- For Ada 95, we just renumber bits within a storage unit. We do the -- same for Ada 83 mode, since we recognize the Bit_Order attribute in -- Ada 83, and are free to add this extension. if Ada_Version < Ada_2005 then Comp := First_Component_Or_Discriminant (R); while Present (Comp) loop CC := Component_Clause (Comp); -- If component clause is present, then deal with the non-default -- bit order case for Ada 95 mode. -- We only do this processing for the base type, and in fact that -- is important, since otherwise if there are record subtypes, we -- could reverse the bits once for each subtype, which is wrong. if Present (CC) and then Ekind (R) = E_Record_Type then declare CFB : constant Uint := Component_Bit_Offset (Comp); CSZ : constant Uint := Esize (Comp); CLC : constant Node_Id := Component_Clause (Comp); Pos : constant Node_Id := Position (CLC); FB : constant Node_Id := First_Bit (CLC); Storage_Unit_Offset : constant Uint := CFB / System_Storage_Unit; Start_Bit : constant Uint := CFB mod System_Storage_Unit; begin -- Cases where field goes over storage unit boundary if Start_Bit + CSZ > System_Storage_Unit then -- Allow multi-byte field but generate warning if Start_Bit mod System_Storage_Unit = 0 and then CSZ mod System_Storage_Unit = 0 then Error_Msg_N ("info: multi-byte field specified with " & "non-standard Bit_Order?V?", CLC); if Bytes_Big_Endian then Error_Msg_N ("\bytes are not reversed " & "(component is big-endian)?V?", CLC); else Error_Msg_N ("\bytes are not reversed " & "(component is little-endian)?V?", CLC); end if; -- Do not allow non-contiguous field else Error_Msg_N ("attempt to specify non-contiguous field " & "not permitted", CLC); Error_Msg_N ("\caused by non-standard Bit_Order " & "specified", CLC); Error_Msg_N ("\consider possibility of using " & "Ada 2005 mode here", CLC); end if; -- Case where field fits in one storage unit else -- Give warning if suspicious component clause if Intval (FB) >= System_Storage_Unit and then Warn_On_Reverse_Bit_Order then Error_Msg_N ("info: Bit_Order clause does not affect " & "byte ordering?V?", Pos); Error_Msg_Uint_1 := Intval (Pos) + Intval (FB) / System_Storage_Unit; Error_Msg_N ("info: position normalized to ^ before bit " & "order interpreted?V?", Pos); end if; -- Here is where we fix up the Component_Bit_Offset value -- to account for the reverse bit order. Some examples of -- what needs to be done are: -- First_Bit .. Last_Bit Component_Bit_Offset -- old new old new -- 0 .. 0 7 .. 7 0 7 -- 0 .. 1 6 .. 7 0 6 -- 0 .. 2 5 .. 7 0 5 -- 0 .. 7 0 .. 7 0 4 -- 1 .. 1 6 .. 6 1 6 -- 1 .. 4 3 .. 6 1 3 -- 4 .. 7 0 .. 3 4 0 -- The rule is that the first bit is is obtained by -- subtracting the old ending bit from storage_unit - 1. Set_Component_Bit_Offset (Comp, (Storage_Unit_Offset * System_Storage_Unit) + (System_Storage_Unit - 1) - (Start_Bit + CSZ - 1)); Set_Normalized_First_Bit (Comp, Component_Bit_Offset (Comp) mod System_Storage_Unit); end if; end; end if; Next_Component_Or_Discriminant (Comp); end loop; -- For Ada 2005, we do machine scalar processing, as fully described In -- AI-133. This involves gathering all components which start at the -- same byte offset and processing them together. Same approach is still -- valid in later versions including Ada 2012. else declare Max_Machine_Scalar_Size : constant Uint := UI_From_Int (Standard_Long_Long_Integer_Size); -- We use this as the maximum machine scalar size Num_CC : Natural; SSU : constant Uint := UI_From_Int (System_Storage_Unit); begin -- This first loop through components does two things. First it -- deals with the case of components with component clauses whose -- length is greater than the maximum machine scalar size (either -- accepting them or rejecting as needed). Second, it counts the -- number of components with component clauses whose length does -- not exceed this maximum for later processing. Num_CC := 0; Comp := First_Component_Or_Discriminant (R); while Present (Comp) loop CC := Component_Clause (Comp); if Present (CC) then declare Fbit : constant Uint := Static_Integer (First_Bit (CC)); Lbit : constant Uint := Static_Integer (Last_Bit (CC)); begin -- Case of component with last bit >= max machine scalar if Lbit >= Max_Machine_Scalar_Size then -- This is allowed only if first bit is zero, and -- last bit + 1 is a multiple of storage unit size. if Fbit = 0 and then (Lbit + 1) mod SSU = 0 then -- This is the case to give a warning if enabled if Warn_On_Reverse_Bit_Order then Error_Msg_N ("info: multi-byte field specified with " & "non-standard Bit_Order?V?", CC); if Bytes_Big_Endian then Error_Msg_N ("\bytes are not reversed " & "(component is big-endian)?V?", CC); else Error_Msg_N ("\bytes are not reversed " & "(component is little-endian)?V?", CC); end if; end if; -- Give error message for RM 13.5.1(10) violation else Error_Msg_FE ("machine scalar rules not followed for&", First_Bit (CC), Comp); Error_Msg_Uint_1 := Lbit + 1; Error_Msg_Uint_2 := Max_Machine_Scalar_Size; Error_Msg_F ("\last bit + 1 (^) exceeds maximum machine " & "scalar size (^)", First_Bit (CC)); if (Lbit + 1) mod SSU /= 0 then Error_Msg_Uint_1 := SSU; Error_Msg_F ("\and is not a multiple of Storage_Unit (^) " & "(RM 13.5.1(10))", First_Bit (CC)); else Error_Msg_Uint_1 := Fbit; Error_Msg_F ("\and first bit (^) is non-zero " & "(RM 13.4.1(10))", First_Bit (CC)); end if; end if; -- OK case of machine scalar related component clause, -- For now, just count them. else Num_CC := Num_CC + 1; end if; end; end if; Next_Component_Or_Discriminant (Comp); end loop; -- We need to sort the component clauses on the basis of the -- Position values in the clause, so we can group clauses with -- the same Position together to determine the relevant machine -- scalar size. Sort_CC : declare Comps : array (0 .. Num_CC) of Entity_Id; -- Array to collect component and discriminant entities. The -- data starts at index 1, the 0'th entry is for the sort -- routine. function CP_Lt (Op1, Op2 : Natural) return Boolean; -- Compare routine for Sort procedure CP_Move (From : Natural; To : Natural); -- Move routine for Sort package Sorting is new GNAT.Heap_Sort_G (CP_Move, CP_Lt); Start : Natural; Stop : Natural; -- Start and stop positions in the component list of the set of -- components with the same starting position (that constitute -- components in a single machine scalar). MaxL : Uint; -- Maximum last bit value of any component in this set MSS : Uint; -- Corresponding machine scalar size ----------- -- CP_Lt -- ----------- function CP_Lt (Op1, Op2 : Natural) return Boolean is begin return Position (Component_Clause (Comps (Op1))) < Position (Component_Clause (Comps (Op2))); end CP_Lt; ------------- -- CP_Move -- ------------- procedure CP_Move (From : Natural; To : Natural) is begin Comps (To) := Comps (From); end CP_Move; -- Start of processing for Sort_CC begin -- Collect the machine scalar relevant component clauses Num_CC := 0; Comp := First_Component_Or_Discriminant (R); while Present (Comp) loop declare CC : constant Node_Id := Component_Clause (Comp); begin -- Collect only component clauses whose last bit is less -- than machine scalar size. Any component clause whose -- last bit exceeds this value does not take part in -- machine scalar layout considerations. The test for -- Error_Posted makes sure we exclude component clauses -- for which we already posted an error. if Present (CC) and then not Error_Posted (Last_Bit (CC)) and then Static_Integer (Last_Bit (CC)) < Max_Machine_Scalar_Size then Num_CC := Num_CC + 1; Comps (Num_CC) := Comp; end if; end; Next_Component_Or_Discriminant (Comp); end loop; -- Sort by ascending position number Sorting.Sort (Num_CC); -- We now have all the components whose size does not exceed -- the max machine scalar value, sorted by starting position. -- In this loop we gather groups of clauses starting at the -- same position, to process them in accordance with AI-133. Stop := 0; while Stop < Num_CC loop Start := Stop + 1; Stop := Start; MaxL := Static_Integer (Last_Bit (Component_Clause (Comps (Start)))); while Stop < Num_CC loop if Static_Integer (Position (Component_Clause (Comps (Stop + 1)))) = Static_Integer (Position (Component_Clause (Comps (Stop)))) then Stop := Stop + 1; MaxL := UI_Max (MaxL, Static_Integer (Last_Bit (Component_Clause (Comps (Stop))))); else exit; end if; end loop; -- Now we have a group of component clauses from Start to -- Stop whose positions are identical, and MaxL is the -- maximum last bit value of any of these components. -- We need to determine the corresponding machine scalar -- size. This loop assumes that machine scalar sizes are -- even, and that each possible machine scalar has twice -- as many bits as the next smaller one. MSS := Max_Machine_Scalar_Size; while MSS mod 2 = 0 and then (MSS / 2) >= SSU and then (MSS / 2) > MaxL loop MSS := MSS / 2; end loop; -- Here is where we fix up the Component_Bit_Offset value -- to account for the reverse bit order. Some examples of -- what needs to be done for the case of a machine scalar -- size of 8 are: -- First_Bit .. Last_Bit Component_Bit_Offset -- old new old new -- 0 .. 0 7 .. 7 0 7 -- 0 .. 1 6 .. 7 0 6 -- 0 .. 2 5 .. 7 0 5 -- 0 .. 7 0 .. 7 0 4 -- 1 .. 1 6 .. 6 1 6 -- 1 .. 4 3 .. 6 1 3 -- 4 .. 7 0 .. 3 4 0 -- The rule is that the first bit is obtained by subtracting -- the old ending bit from machine scalar size - 1. for C in Start .. Stop loop declare Comp : constant Entity_Id := Comps (C); CC : constant Node_Id := Component_Clause (Comp); LB : constant Uint := Static_Integer (Last_Bit (CC)); NFB : constant Uint := MSS - Uint_1 - LB; NLB : constant Uint := NFB + Esize (Comp) - 1; Pos : constant Uint := Static_Integer (Position (CC)); begin if Warn_On_Reverse_Bit_Order then Error_Msg_Uint_1 := MSS; Error_Msg_N ("info: reverse bit order in machine " & "scalar of length^?V?", First_Bit (CC)); Error_Msg_Uint_1 := NFB; Error_Msg_Uint_2 := NLB; if Bytes_Big_Endian then Error_Msg_NE ("\big-endian range for component " & "& is ^ .. ^?V?", First_Bit (CC), Comp); else Error_Msg_NE ("\little-endian range for component" & "& is ^ .. ^?V?", First_Bit (CC), Comp); end if; end if; Set_Component_Bit_Offset (Comp, Pos * SSU + NFB); Set_Normalized_First_Bit (Comp, NFB mod SSU); end; end loop; end loop; end Sort_CC; end; end if; end Adjust_Record_For_Reverse_Bit_Order; ------------------------------------- -- Alignment_Check_For_Size_Change -- ------------------------------------- procedure Alignment_Check_For_Size_Change (Typ : Entity_Id; Size : Uint) is begin -- If the alignment is known, and not set by a rep clause, and is -- inconsistent with the size being set, then reset it to unknown, -- we assume in this case that the size overrides the inherited -- alignment, and that the alignment must be recomputed. if Known_Alignment (Typ) and then not Has_Alignment_Clause (Typ) and then Size mod (Alignment (Typ) * SSU) /= 0 then Init_Alignment (Typ); end if; end Alignment_Check_For_Size_Change; ------------------------------------- -- Analyze_Aspects_At_Freeze_Point -- ------------------------------------- procedure Analyze_Aspects_At_Freeze_Point (E : Entity_Id) is procedure Analyze_Aspect_Default_Value (ASN : Node_Id); -- This routine analyzes an Aspect_Default_[Component_]Value denoted by -- the aspect specification node ASN. procedure Inherit_Delayed_Rep_Aspects (ASN : Node_Id); -- As discussed in the spec of Aspects (see Aspect_Delay declaration), -- a derived type can inherit aspects from its parent which have been -- specified at the time of the derivation using an aspect, as in: -- -- type A is range 1 .. 10 -- with Size => Not_Defined_Yet; -- .. -- type B is new A; -- .. -- Not_Defined_Yet : constant := 64; -- -- In this example, the Size of A is considered to be specified prior -- to the derivation, and thus inherited, even though the value is not -- known at the time of derivation. To deal with this, we use two entity -- flags. The flag Has_Derived_Rep_Aspects is set in the parent type (A -- here), and then the flag May_Inherit_Delayed_Rep_Aspects is set in -- the derived type (B here). If this flag is set when the derived type -- is frozen, then this procedure is called to ensure proper inheritance -- of all delayed aspects from the parent type. The derived type is E, -- the argument to Analyze_Aspects_At_Freeze_Point. ASN is the first -- aspect specification node in the Rep_Item chain for the parent type. procedure Make_Pragma_From_Boolean_Aspect (ASN : Node_Id); -- Given an aspect specification node ASN whose expression is an -- optional Boolean, this routines creates the corresponding pragma -- at the freezing point. ---------------------------------- -- Analyze_Aspect_Default_Value -- ---------------------------------- procedure Analyze_Aspect_Default_Value (ASN : Node_Id) is A_Id : constant Aspect_Id := Get_Aspect_Id (ASN); Ent : constant Entity_Id := Entity (ASN); Expr : constant Node_Id := Expression (ASN); Id : constant Node_Id := Identifier (ASN); begin Error_Msg_Name_1 := Chars (Id); if not Is_Type (Ent) then Error_Msg_N ("aspect% can only apply to a type", Id); return; elsif not Is_First_Subtype (Ent) then Error_Msg_N ("aspect% cannot apply to subtype", Id); return; elsif A_Id = Aspect_Default_Value and then not Is_Scalar_Type (Ent) then Error_Msg_N ("aspect% can only be applied to scalar type", Id); return; elsif A_Id = Aspect_Default_Component_Value then if not Is_Array_Type (Ent) then Error_Msg_N ("aspect% can only be applied to array type", Id); return; elsif not Is_Scalar_Type (Component_Type (Ent)) then Error_Msg_N ("aspect% requires scalar components", Id); return; end if; end if; Set_Has_Default_Aspect (Base_Type (Ent)); if Is_Scalar_Type (Ent) then Set_Default_Aspect_Value (Base_Type (Ent), Expr); else Set_Default_Aspect_Component_Value (Base_Type (Ent), Expr); end if; end Analyze_Aspect_Default_Value; --------------------------------- -- Inherit_Delayed_Rep_Aspects -- --------------------------------- procedure Inherit_Delayed_Rep_Aspects (ASN : Node_Id) is A_Id : constant Aspect_Id := Get_Aspect_Id (ASN); P : constant Entity_Id := Entity (ASN); -- Entithy for parent type N : Node_Id; -- Item from Rep_Item chain A : Aspect_Id; begin -- Loop through delayed aspects for the parent type N := ASN; while Present (N) loop if Nkind (N) = N_Aspect_Specification then exit when Entity (N) /= P; if Is_Delayed_Aspect (N) then A := Get_Aspect_Id (Chars (Identifier (N))); -- Process delayed rep aspect. For Boolean attributes it is -- not possible to cancel an attribute once set (the attempt -- to use an aspect with xxx => False is an error) for a -- derived type. So for those cases, we do not have to check -- if a clause has been given for the derived type, since it -- is harmless to set it again if it is already set. case A is -- Alignment when Aspect_Alignment => if not Has_Alignment_Clause (E) then Set_Alignment (E, Alignment (P)); end if; -- Atomic when Aspect_Atomic => if Is_Atomic (P) then Set_Is_Atomic (E); end if; -- Atomic_Components when Aspect_Atomic_Components => if Has_Atomic_Components (P) then Set_Has_Atomic_Components (Base_Type (E)); end if; -- Bit_Order when Aspect_Bit_Order => if Is_Record_Type (E) and then No (Get_Attribute_Definition_Clause (E, Attribute_Bit_Order)) and then Reverse_Bit_Order (P) then Set_Reverse_Bit_Order (Base_Type (E)); end if; -- Component_Size when Aspect_Component_Size => if Is_Array_Type (E) and then not Has_Component_Size_Clause (E) then Set_Component_Size (Base_Type (E), Component_Size (P)); end if; -- Machine_Radix when Aspect_Machine_Radix => if Is_Decimal_Fixed_Point_Type (E) and then not Has_Machine_Radix_Clause (E) then Set_Machine_Radix_10 (E, Machine_Radix_10 (P)); end if; -- Object_Size (also Size which also sets Object_Size) when Aspect_Object_Size | Aspect_Size => if not Has_Size_Clause (E) and then No (Get_Attribute_Definition_Clause (E, Attribute_Object_Size)) then Set_Esize (E, Esize (P)); end if; -- Pack when Aspect_Pack => if not Is_Packed (E) then Set_Is_Packed (Base_Type (E)); if Is_Bit_Packed_Array (P) then Set_Is_Bit_Packed_Array (Base_Type (E)); Set_Packed_Array_Impl_Type (E, Packed_Array_Impl_Type (P)); end if; end if; -- Scalar_Storage_Order when Aspect_Scalar_Storage_Order => if (Is_Record_Type (E) or else Is_Array_Type (E)) and then No (Get_Attribute_Definition_Clause (E, Attribute_Scalar_Storage_Order)) and then Reverse_Storage_Order (P) then Set_Reverse_Storage_Order (Base_Type (E)); -- Clear default SSO indications, since the aspect -- overrides the default. Set_SSO_Set_Low_By_Default (Base_Type (E), False); Set_SSO_Set_High_By_Default (Base_Type (E), False); end if; -- Small when Aspect_Small => if Is_Fixed_Point_Type (E) and then not Has_Small_Clause (E) then Set_Small_Value (E, Small_Value (P)); end if; -- Storage_Size when Aspect_Storage_Size => if (Is_Access_Type (E) or else Is_Task_Type (E)) and then not Has_Storage_Size_Clause (E) then Set_Storage_Size_Variable (Base_Type (E), Storage_Size_Variable (P)); end if; -- Value_Size when Aspect_Value_Size => -- Value_Size is never inherited, it is either set by -- default, or it is explicitly set for the derived -- type. So nothing to do here. null; -- Volatile when Aspect_Volatile => if Is_Volatile (P) then Set_Is_Volatile (E); end if; -- Volatile_Full_Access when Aspect_Volatile_Full_Access => if Is_Volatile_Full_Access (P) then Set_Is_Volatile_Full_Access (E); end if; -- Volatile_Components when Aspect_Volatile_Components => if Has_Volatile_Components (P) then Set_Has_Volatile_Components (Base_Type (E)); end if; -- That should be all the Rep Aspects when others => pragma Assert (Aspect_Delay (A_Id) /= Rep_Aspect); null; end case; end if; end if; N := Next_Rep_Item (N); end loop; end Inherit_Delayed_Rep_Aspects; ------------------------------------- -- Make_Pragma_From_Boolean_Aspect -- ------------------------------------- procedure Make_Pragma_From_Boolean_Aspect (ASN : Node_Id) is Ident : constant Node_Id := Identifier (ASN); A_Name : constant Name_Id := Chars (Ident); A_Id : constant Aspect_Id := Get_Aspect_Id (A_Name); Ent : constant Entity_Id := Entity (ASN); Expr : constant Node_Id := Expression (ASN); Loc : constant Source_Ptr := Sloc (ASN); procedure Check_False_Aspect_For_Derived_Type; -- This procedure checks for the case of a false aspect for a derived -- type, which improperly tries to cancel an aspect inherited from -- the parent. ----------------------------------------- -- Check_False_Aspect_For_Derived_Type -- ----------------------------------------- procedure Check_False_Aspect_For_Derived_Type is Par : Node_Id; begin -- We are only checking derived types if not Is_Derived_Type (E) then return; end if; Par := Nearest_Ancestor (E); case A_Id is when Aspect_Atomic | Aspect_Shared => if not Is_Atomic (Par) then return; end if; when Aspect_Atomic_Components => if not Has_Atomic_Components (Par) then return; end if; when Aspect_Discard_Names => if not Discard_Names (Par) then return; end if; when Aspect_Pack => if not Is_Packed (Par) then return; end if; when Aspect_Unchecked_Union => if not Is_Unchecked_Union (Par) then return; end if; when Aspect_Volatile => if not Is_Volatile (Par) then return; end if; when Aspect_Volatile_Components => if not Has_Volatile_Components (Par) then return; end if; when Aspect_Volatile_Full_Access => if not Is_Volatile_Full_Access (Par) then return; end if; when others => return; end case; -- Fall through means we are canceling an inherited aspect Error_Msg_Name_1 := A_Name; Error_Msg_NE ("derived type& inherits aspect%, cannot cancel", Expr, E); end Check_False_Aspect_For_Derived_Type; -- Local variables Prag : Node_Id; -- Start of processing for Make_Pragma_From_Boolean_Aspect begin -- Note that we know Expr is present, because for a missing Expr -- argument, we knew it was True and did not need to delay the -- evaluation to the freeze point. if Is_False (Static_Boolean (Expr)) then Check_False_Aspect_For_Derived_Type; else Prag := Make_Pragma (Loc, Pragma_Identifier => Make_Identifier (Sloc (Ident), Chars (Ident)), Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Sloc (Ident), Expression => New_Occurrence_Of (Ent, Sloc (Ident))))); Set_From_Aspect_Specification (Prag, True); Set_Corresponding_Aspect (Prag, ASN); Set_Aspect_Rep_Item (ASN, Prag); Set_Is_Delayed_Aspect (Prag); Set_Parent (Prag, ASN); end if; end Make_Pragma_From_Boolean_Aspect; -- Local variables A_Id : Aspect_Id; ASN : Node_Id; Ritem : Node_Id; -- Start of processing for Analyze_Aspects_At_Freeze_Point begin -- Must be visible in current scope if not Scope_Within_Or_Same (Current_Scope, Scope (E)) then return; end if; -- Look for aspect specification entries for this entity ASN := First_Rep_Item (E); while Present (ASN) loop if Nkind (ASN) = N_Aspect_Specification then exit when Entity (ASN) /= E; if Is_Delayed_Aspect (ASN) then A_Id := Get_Aspect_Id (ASN); case A_Id is -- For aspects whose expression is an optional Boolean, make -- the corresponding pragma at the freeze point. when Boolean_Aspects | Library_Unit_Aspects => -- Aspects Export and Import require special handling. -- Both are by definition Boolean and may benefit from -- forward references, however their expressions are -- treated as static. In addition, the syntax of their -- corresponding pragmas requires extra "pieces" which -- may also contain forward references. To account for -- all of this, the corresponding pragma is created by -- Analyze_Aspect_Export_Import, but is not analyzed as -- the complete analysis must happen now. if A_Id = Aspect_Export or else A_Id = Aspect_Import then null; -- Otherwise create a corresponding pragma else Make_Pragma_From_Boolean_Aspect (ASN); end if; -- Special handling for aspects that don't correspond to -- pragmas/attributes. when Aspect_Default_Value | Aspect_Default_Component_Value => -- Do not inherit aspect for anonymous base type of a -- scalar or array type, because they apply to the first -- subtype of the type, and will be processed when that -- first subtype is frozen. if Is_Derived_Type (E) and then not Comes_From_Source (E) and then E /= First_Subtype (E) then null; else Analyze_Aspect_Default_Value (ASN); end if; -- Ditto for iterator aspects, because the corresponding -- attributes may not have been analyzed yet. when Aspect_Constant_Indexing | Aspect_Variable_Indexing | Aspect_Default_Iterator | Aspect_Iterator_Element => Analyze (Expression (ASN)); if Etype (Expression (ASN)) = Any_Type then Error_Msg_NE ("\aspect must be fully defined before & is frozen", ASN, E); end if; when Aspect_Iterable => Validate_Iterable_Aspect (E, ASN); when others => null; end case; Ritem := Aspect_Rep_Item (ASN); if Present (Ritem) then Analyze (Ritem); end if; end if; end if; Next_Rep_Item (ASN); end loop; -- This is where we inherit delayed rep aspects from our parent. Note -- that if we fell out of the above loop with ASN non-empty, it means -- we hit an aspect for an entity other than E, and it must be the -- type from which we were derived. if May_Inherit_Delayed_Rep_Aspects (E) then Inherit_Delayed_Rep_Aspects (ASN); end if; end Analyze_Aspects_At_Freeze_Point; ----------------------------------- -- Analyze_Aspect_Specifications -- ----------------------------------- procedure Analyze_Aspect_Specifications (N : Node_Id; E : Entity_Id) is procedure Decorate (Asp : Node_Id; Prag : Node_Id); -- Establish linkages between an aspect and its corresponding pragma procedure Insert_Pragma (Prag : Node_Id; Is_Instance : Boolean := False); -- Subsidiary to the analysis of aspects -- Abstract_State -- Attach_Handler -- Contract_Cases -- Depends -- Ghost -- Global -- Initial_Condition -- Initializes -- Post -- Pre -- Refined_Depends -- Refined_Global -- Refined_State -- SPARK_Mode -- Warnings -- Insert pragma Prag such that it mimics the placement of a source -- pragma of the same kind. Flag Is_Generic should be set when the -- context denotes a generic instance. -------------- -- Decorate -- -------------- procedure Decorate (Asp : Node_Id; Prag : Node_Id) is begin Set_Aspect_Rep_Item (Asp, Prag); Set_Corresponding_Aspect (Prag, Asp); Set_From_Aspect_Specification (Prag); Set_Parent (Prag, Asp); end Decorate; ------------------- -- Insert_Pragma -- ------------------- procedure Insert_Pragma (Prag : Node_Id; Is_Instance : Boolean := False) is Aux : Node_Id; Decl : Node_Id; Decls : List_Id; Def : Node_Id; Inserted : Boolean := False; begin -- When the aspect appears on an entry, package, protected unit, -- subprogram, or task unit body, insert the generated pragma at the -- top of the body declarations to emulate the behavior of a source -- pragma. -- package body Pack with Aspect is -- package body Pack is -- pragma Prag; if Nkind_In (N, N_Entry_Body, N_Package_Body, N_Protected_Body, N_Subprogram_Body, N_Task_Body) then Decls := Declarations (N); if No (Decls) then Decls := New_List; Set_Declarations (N, Decls); end if; Prepend_To (Decls, Prag); -- When the aspect is associated with a [generic] package declaration -- insert the generated pragma at the top of the visible declarations -- to emulate the behavior of a source pragma. -- package Pack with Aspect is -- package Pack is -- pragma Prag; elsif Nkind_In (N, N_Generic_Package_Declaration, N_Package_Declaration) then Decls := Visible_Declarations (Specification (N)); if No (Decls) then Decls := New_List; Set_Visible_Declarations (Specification (N), Decls); end if; -- The visible declarations of a generic instance have the -- following structure: -- -- -- -- Insert the pragma before the first source declaration by -- skipping the instance "header" to ensure proper visibility of -- all formals. if Is_Instance then Decl := First (Decls); while Present (Decl) loop if Comes_From_Source (Decl) then Insert_Before (Decl, Prag); Inserted := True; exit; else Next (Decl); end if; end loop; -- The pragma is placed after the instance "header" if not Inserted then Append_To (Decls, Prag); end if; -- Otherwise this is not a generic instance else Prepend_To (Decls, Prag); end if; -- When the aspect is associated with a protected unit declaration, -- insert the generated pragma at the top of the visible declarations -- the emulate the behavior of a source pragma. -- protected [type] Prot with Aspect is -- protected [type] Prot is -- pragma Prag; elsif Nkind (N) = N_Protected_Type_Declaration then Def := Protected_Definition (N); if No (Def) then Def := Make_Protected_Definition (Sloc (N), Visible_Declarations => New_List, End_Label => Empty); Set_Protected_Definition (N, Def); end if; Decls := Visible_Declarations (Def); if No (Decls) then Decls := New_List; Set_Visible_Declarations (Def, Decls); end if; Prepend_To (Decls, Prag); -- When the aspect is associated with a task unit declaration, insert -- insert the generated pragma at the top of the visible declarations -- the emulate the behavior of a source pragma. -- task [type] Prot with Aspect is -- task [type] Prot is -- pragma Prag; elsif Nkind (N) = N_Task_Type_Declaration then Def := Task_Definition (N); if No (Def) then Def := Make_Task_Definition (Sloc (N), Visible_Declarations => New_List, End_Label => Empty); Set_Task_Definition (N, Def); end if; Decls := Visible_Declarations (Def); if No (Decls) then Decls := New_List; Set_Visible_Declarations (Def, Decls); end if; Prepend_To (Decls, Prag); -- When the context is a library unit, the pragma is added to the -- Pragmas_After list. elsif Nkind (Parent (N)) = N_Compilation_Unit then Aux := Aux_Decls_Node (Parent (N)); if No (Pragmas_After (Aux)) then Set_Pragmas_After (Aux, New_List); end if; Prepend (Prag, Pragmas_After (Aux)); -- Default, the pragma is inserted after the context else Insert_After (N, Prag); end if; end Insert_Pragma; -- Local variables Aspect : Node_Id; Aitem : Node_Id; Ent : Node_Id; L : constant List_Id := Aspect_Specifications (N); Ins_Node : Node_Id := N; -- Insert pragmas/attribute definition clause after this node when no -- delayed analysis is required. -- Start of processing for Analyze_Aspect_Specifications begin -- The general processing involves building an attribute definition -- clause or a pragma node that corresponds to the aspect. Then in order -- to delay the evaluation of this aspect to the freeze point, we attach -- the corresponding pragma/attribute definition clause to the aspect -- specification node, which is then placed in the Rep Item chain. In -- this case we mark the entity by setting the flag Has_Delayed_Aspects -- and we evaluate the rep item at the freeze point. When the aspect -- doesn't have a corresponding pragma/attribute definition clause, then -- its analysis is simply delayed at the freeze point. -- Some special cases don't require delay analysis, thus the aspect is -- analyzed right now. -- Note that there is a special handling for Pre, Post, Test_Case, -- Contract_Cases aspects. In these cases, we do not have to worry -- about delay issues, since the pragmas themselves deal with delay -- of visibility for the expression analysis. Thus, we just insert -- the pragma after the node N. pragma Assert (Present (L)); -- Loop through aspects Aspect := First (L); Aspect_Loop : while Present (Aspect) loop Analyze_One_Aspect : declare Expr : constant Node_Id := Expression (Aspect); Id : constant Node_Id := Identifier (Aspect); Loc : constant Source_Ptr := Sloc (Aspect); Nam : constant Name_Id := Chars (Id); A_Id : constant Aspect_Id := Get_Aspect_Id (Nam); Anod : Node_Id; Delay_Required : Boolean; -- Set False if delay is not required Eloc : Source_Ptr := No_Location; -- Source location of expression, modified when we split PPC's. It -- is set below when Expr is present. procedure Analyze_Aspect_Convention; -- Perform analysis of aspect Convention procedure Analyze_Aspect_Export_Import; -- Perform analysis of aspects Export or Import procedure Analyze_Aspect_External_Link_Name; -- Perform analysis of aspects External_Name or Link_Name procedure Analyze_Aspect_Implicit_Dereference; -- Perform analysis of the Implicit_Dereference aspects procedure Make_Aitem_Pragma (Pragma_Argument_Associations : List_Id; Pragma_Name : Name_Id); -- This is a wrapper for Make_Pragma used for converting aspects -- to pragmas. It takes care of Sloc (set from Loc) and building -- the pragma identifier from the given name. In addition the -- flags Class_Present and Split_PPC are set from the aspect -- node, as well as Is_Ignored. This routine also sets the -- From_Aspect_Specification in the resulting pragma node to -- True, and sets Corresponding_Aspect to point to the aspect. -- The resulting pragma is assigned to Aitem. ------------------------------- -- Analyze_Aspect_Convention -- ------------------------------- procedure Analyze_Aspect_Convention is Conv : Node_Id; Dummy_1 : Node_Id; Dummy_2 : Node_Id; Dummy_3 : Node_Id; Expo : Node_Id; Imp : Node_Id; begin -- Obtain all interfacing aspects that apply to the related -- entity. Get_Interfacing_Aspects (Iface_Asp => Aspect, Conv_Asp => Dummy_1, EN_Asp => Dummy_2, Expo_Asp => Expo, Imp_Asp => Imp, LN_Asp => Dummy_3, Do_Checks => True); -- The related entity is subject to aspect Export or Import. -- Do not process Convention now because it must be analysed -- as part of Export or Import. if Present (Expo) or else Present (Imp) then return; -- Otherwise Convention appears by itself else -- The aspect specifies a particular convention if Present (Expr) then Conv := New_Copy_Tree (Expr); -- Otherwise assume convention Ada else Conv := Make_Identifier (Loc, Name_Ada); end if; -- Generate: -- pragma Convention (, ); Make_Aitem_Pragma (Pragma_Name => Name_Convention, Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Conv), Make_Pragma_Argument_Association (Loc, Expression => New_Occurrence_Of (E, Loc)))); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); end if; end Analyze_Aspect_Convention; ---------------------------------- -- Analyze_Aspect_Export_Import -- ---------------------------------- procedure Analyze_Aspect_Export_Import is Dummy_1 : Node_Id; Dummy_2 : Node_Id; Dummy_3 : Node_Id; Expo : Node_Id; Imp : Node_Id; begin -- Obtain all interfacing aspects that apply to the related -- entity. Get_Interfacing_Aspects (Iface_Asp => Aspect, Conv_Asp => Dummy_1, EN_Asp => Dummy_2, Expo_Asp => Expo, Imp_Asp => Imp, LN_Asp => Dummy_3, Do_Checks => True); -- The related entity cannot be subject to both aspects Export -- and Import. if Present (Expo) and then Present (Imp) then Error_Msg_N ("incompatible interfacing aspects given for &", E); Error_Msg_Sloc := Sloc (Expo); Error_Msg_N ("\aspect `Export` #", E); Error_Msg_Sloc := Sloc (Imp); Error_Msg_N ("\aspect `Import` #", E); end if; -- A variable is most likely modified from the outside. Take -- Take the optimistic approach to avoid spurious errors. if Ekind (E) = E_Variable then Set_Never_Set_In_Source (E, False); end if; -- Resolve the expression of an Import or Export here, and -- require it to be of type Boolean and static. This is not -- quite right, because in general this should be delayed, -- but that seems tricky for these, because normally Boolean -- aspects are replaced with pragmas at the freeze point in -- Make_Pragma_From_Boolean_Aspect. if not Present (Expr) or else Is_True (Static_Boolean (Expr)) then if A_Id = Aspect_Import then Set_Has_Completion (E); Set_Is_Imported (E); -- An imported object cannot be explicitly initialized if Nkind (N) = N_Object_Declaration and then Present (Expression (N)) then Error_Msg_N ("imported entities cannot be initialized " & "(RM B.1(24))", Expression (N)); end if; else pragma Assert (A_Id = Aspect_Export); Set_Is_Exported (E); end if; -- Create the proper form of pragma Export or Import taking -- into account Conversion, External_Name, and Link_Name. Aitem := Build_Export_Import_Pragma (Aspect, E); -- Otherwise the expression is either False or erroneous. There -- is no corresponding pragma. else Aitem := Empty; end if; end Analyze_Aspect_Export_Import; --------------------------------------- -- Analyze_Aspect_External_Link_Name -- --------------------------------------- procedure Analyze_Aspect_External_Link_Name is Dummy_1 : Node_Id; Dummy_2 : Node_Id; Dummy_3 : Node_Id; Expo : Node_Id; Imp : Node_Id; begin -- Obtain all interfacing aspects that apply to the related -- entity. Get_Interfacing_Aspects (Iface_Asp => Aspect, Conv_Asp => Dummy_1, EN_Asp => Dummy_2, Expo_Asp => Expo, Imp_Asp => Imp, LN_Asp => Dummy_3, Do_Checks => True); -- Ensure that aspect External_Name applies to aspect Export or -- Import. if A_Id = Aspect_External_Name then if No (Expo) and then No (Imp) then Error_Msg_N ("aspect `External_Name` requires aspect `Import` or " & "`Export`", Aspect); end if; -- Otherwise ensure that aspect Link_Name applies to aspect -- Export or Import. else pragma Assert (A_Id = Aspect_Link_Name); if No (Expo) and then No (Imp) then Error_Msg_N ("aspect `Link_Name` requires aspect `Import` or " & "`Export`", Aspect); end if; end if; end Analyze_Aspect_External_Link_Name; ----------------------------------------- -- Analyze_Aspect_Implicit_Dereference -- ----------------------------------------- procedure Analyze_Aspect_Implicit_Dereference is Disc : Entity_Id; Parent_Disc : Entity_Id; begin if not Is_Type (E) or else not Has_Discriminants (E) then Error_Msg_N ("aspect must apply to a type with discriminants", Expr); elsif not Is_Entity_Name (Expr) then Error_Msg_N ("aspect must name a discriminant of current type", Expr); else Disc := First_Discriminant (E); while Present (Disc) loop if Chars (Expr) = Chars (Disc) and then Ekind (Etype (Disc)) = E_Anonymous_Access_Type then Set_Has_Implicit_Dereference (E); Set_Has_Implicit_Dereference (Disc); exit; end if; Next_Discriminant (Disc); end loop; -- Error if no proper access discriminant if No (Disc) then Error_Msg_NE ("not an access discriminant of&", Expr, E); return; end if; end if; -- For a type extension, check whether parent has a -- reference discriminant, to verify that use is proper. if Is_Derived_Type (E) and then Has_Discriminants (Etype (E)) then Parent_Disc := Get_Reference_Discriminant (Etype (E)); if Present (Parent_Disc) and then Corresponding_Discriminant (Disc) /= Parent_Disc then Error_Msg_N ("reference discriminant does not match discriminant " & "of parent type", Expr); end if; end if; end Analyze_Aspect_Implicit_Dereference; ----------------------- -- Make_Aitem_Pragma -- ----------------------- procedure Make_Aitem_Pragma (Pragma_Argument_Associations : List_Id; Pragma_Name : Name_Id) is Args : List_Id := Pragma_Argument_Associations; begin -- We should never get here if aspect was disabled pragma Assert (not Is_Disabled (Aspect)); -- Certain aspects allow for an optional name or expression. Do -- not generate a pragma with empty argument association list. if No (Args) or else No (Expression (First (Args))) then Args := No_List; end if; -- Build the pragma Aitem := Make_Pragma (Loc, Pragma_Argument_Associations => Args, Pragma_Identifier => Make_Identifier (Sloc (Id), Pragma_Name), Class_Present => Class_Present (Aspect), Split_PPC => Split_PPC (Aspect)); -- Set additional semantic fields if Is_Ignored (Aspect) then Set_Is_Ignored (Aitem); elsif Is_Checked (Aspect) then Set_Is_Checked (Aitem); end if; Set_Corresponding_Aspect (Aitem, Aspect); Set_From_Aspect_Specification (Aitem); end Make_Aitem_Pragma; -- Start of processing for Analyze_One_Aspect begin -- Skip aspect if already analyzed, to avoid looping in some cases if Analyzed (Aspect) then goto Continue; end if; -- Skip looking at aspect if it is totally disabled. Just mark it -- as such for later reference in the tree. This also sets the -- Is_Ignored and Is_Checked flags appropriately. Check_Applicable_Policy (Aspect); if Is_Disabled (Aspect) then goto Continue; end if; -- Set the source location of expression, used in the case of -- a failed precondition/postcondition or invariant. Note that -- the source location of the expression is not usually the best -- choice here. For example, it gets located on the last AND -- keyword in a chain of boolean expressiond AND'ed together. -- It is best to put the message on the first character of the -- assertion, which is the effect of the First_Node call here. if Present (Expr) then Eloc := Sloc (First_Node (Expr)); end if; -- Check restriction No_Implementation_Aspect_Specifications if Implementation_Defined_Aspect (A_Id) then Check_Restriction (No_Implementation_Aspect_Specifications, Aspect); end if; -- Check restriction No_Specification_Of_Aspect Check_Restriction_No_Specification_Of_Aspect (Aspect); -- Mark aspect analyzed (actual analysis is delayed till later) Set_Analyzed (Aspect); Set_Entity (Aspect, E); Ent := New_Occurrence_Of (E, Sloc (Id)); -- Check for duplicate aspect. Note that the Comes_From_Source -- test allows duplicate Pre/Post's that we generate internally -- to escape being flagged here. if No_Duplicates_Allowed (A_Id) then Anod := First (L); while Anod /= Aspect loop if Comes_From_Source (Aspect) and then Same_Aspect (A_Id, Get_Aspect_Id (Anod)) then Error_Msg_Name_1 := Nam; Error_Msg_Sloc := Sloc (Anod); -- Case of same aspect specified twice if Class_Present (Anod) = Class_Present (Aspect) then if not Class_Present (Anod) then Error_Msg_NE ("aspect% for & previously given#", Id, E); else Error_Msg_NE ("aspect `%''Class` for & previously given#", Id, E); end if; end if; end if; Next (Anod); end loop; end if; -- Check some general restrictions on language defined aspects if not Implementation_Defined_Aspect (A_Id) then Error_Msg_Name_1 := Nam; -- Not allowed for renaming declarations. Examine the original -- node because a subprogram renaming may have been rewritten -- as a body. if Nkind (Original_Node (N)) in N_Renaming_Declaration then Error_Msg_N ("aspect % not allowed for renaming declaration", Aspect); end if; -- Not allowed for formal type declarations if Nkind (N) = N_Formal_Type_Declaration then Error_Msg_N ("aspect % not allowed for formal type declaration", Aspect); end if; end if; -- Copy expression for later processing by the procedures -- Check_Aspect_At_[Freeze_Point | End_Of_Declarations] Set_Entity (Id, New_Copy_Tree (Expr)); -- Set Delay_Required as appropriate to aspect case Aspect_Delay (A_Id) is when Always_Delay => Delay_Required := True; when Never_Delay => Delay_Required := False; when Rep_Aspect => -- If expression has the form of an integer literal, then -- do not delay, since we know the value cannot change. -- This optimization catches most rep clause cases. -- For Boolean aspects, don't delay if no expression if A_Id in Boolean_Aspects and then No (Expr) then Delay_Required := False; -- For non-Boolean aspects, don't delay if integer literal elsif A_Id not in Boolean_Aspects and then Present (Expr) and then Nkind (Expr) = N_Integer_Literal then Delay_Required := False; -- All other cases are delayed else Delay_Required := True; Set_Has_Delayed_Rep_Aspects (E); end if; end case; -- Processing based on specific aspect case A_Id is when Aspect_Unimplemented => null; -- ??? temp for now -- No_Aspect should be impossible when No_Aspect => raise Program_Error; -- Case 1: Aspects corresponding to attribute definition -- clauses. when Aspect_Address | Aspect_Alignment | Aspect_Bit_Order | Aspect_Component_Size | Aspect_Constant_Indexing | Aspect_Default_Iterator | Aspect_Dispatching_Domain | Aspect_External_Tag | Aspect_Input | Aspect_Iterable | Aspect_Iterator_Element | Aspect_Machine_Radix | Aspect_Object_Size | Aspect_Output | Aspect_Read | Aspect_Scalar_Storage_Order | Aspect_Size | Aspect_Small | Aspect_Simple_Storage_Pool | Aspect_Storage_Pool | Aspect_Stream_Size | Aspect_Value_Size | Aspect_Variable_Indexing | Aspect_Write => -- Indexing aspects apply only to tagged type if (A_Id = Aspect_Constant_Indexing or else A_Id = Aspect_Variable_Indexing) and then not (Is_Type (E) and then Is_Tagged_Type (E)) then Error_Msg_N ("indexing aspect can only apply to a tagged type", Aspect); goto Continue; end if; -- For the case of aspect Address, we don't consider that we -- know the entity is never set in the source, since it is -- is likely aliasing is occurring. -- Note: one might think that the analysis of the resulting -- attribute definition clause would take care of that, but -- that's not the case since it won't be from source. if A_Id = Aspect_Address then Set_Never_Set_In_Source (E, False); end if; -- Correctness of the profile of a stream operation is -- verified at the freeze point, but we must detect the -- illegal specification of this aspect for a subtype now, -- to prevent malformed rep_item chains. if A_Id = Aspect_Input or else A_Id = Aspect_Output or else A_Id = Aspect_Read or else A_Id = Aspect_Write then if not Is_First_Subtype (E) then Error_Msg_N ("local name must be a first subtype", Aspect); goto Continue; -- If stream aspect applies to the class-wide type, -- the generated attribute definition applies to the -- class-wide type as well. elsif Class_Present (Aspect) then Ent := Make_Attribute_Reference (Loc, Prefix => Ent, Attribute_Name => Name_Class); end if; end if; -- Construct the attribute definition clause Aitem := Make_Attribute_Definition_Clause (Loc, Name => Ent, Chars => Chars (Id), Expression => Relocate_Node (Expr)); -- If the address is specified, then we treat the entity as -- referenced, to avoid spurious warnings. This is analogous -- to what is done with an attribute definition clause, but -- here we don't want to generate a reference because this -- is the point of definition of the entity. if A_Id = Aspect_Address then Set_Referenced (E); end if; -- Case 2: Aspects corresponding to pragmas -- Case 2a: Aspects corresponding to pragmas with two -- arguments, where the first argument is a local name -- referring to the entity, and the second argument is the -- aspect definition expression. -- Linker_Section/Suppress/Unsuppress when Aspect_Linker_Section | Aspect_Suppress | Aspect_Unsuppress => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => New_Occurrence_Of (E, Loc)), Make_Pragma_Argument_Association (Sloc (Expr), Expression => Relocate_Node (Expr))), Pragma_Name => Chars (Id)); -- Synchronization -- Corresponds to pragma Implemented, construct the pragma when Aspect_Synchronization => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => New_Occurrence_Of (E, Loc)), Make_Pragma_Argument_Association (Sloc (Expr), Expression => Relocate_Node (Expr))), Pragma_Name => Name_Implemented); -- Attach_Handler when Aspect_Attach_Handler => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Sloc (Ent), Expression => Ent), Make_Pragma_Argument_Association (Sloc (Expr), Expression => Relocate_Node (Expr))), Pragma_Name => Name_Attach_Handler); -- We need to insert this pragma into the tree to get proper -- processing and to look valid from a placement viewpoint. Insert_Pragma (Aitem); goto Continue; -- Dynamic_Predicate, Predicate, Static_Predicate when Aspect_Dynamic_Predicate | Aspect_Predicate | Aspect_Static_Predicate => -- These aspects apply only to subtypes if not Is_Type (E) then Error_Msg_N ("predicate can only be specified for a subtype", Aspect); goto Continue; elsif Is_Incomplete_Type (E) then Error_Msg_N ("predicate cannot apply to incomplete view", Aspect); goto Continue; end if; -- Construct the pragma (always a pragma Predicate, with -- flags recording whether it is static/dynamic). We also -- set flags recording this in the type itself. Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Sloc (Ent), Expression => Ent), Make_Pragma_Argument_Association (Sloc (Expr), Expression => Relocate_Node (Expr))), Pragma_Name => Name_Predicate); -- Mark type has predicates, and remember what kind of -- aspect lead to this predicate (we need this to access -- the right set of check policies later on). Set_Has_Predicates (E); if A_Id = Aspect_Dynamic_Predicate then Set_Has_Dynamic_Predicate_Aspect (E); elsif A_Id = Aspect_Static_Predicate then Set_Has_Static_Predicate_Aspect (E); end if; -- If the type is private, indicate that its completion -- has a freeze node, because that is the one that will -- be visible at freeze time. if Is_Private_Type (E) and then Present (Full_View (E)) then Set_Has_Predicates (Full_View (E)); if A_Id = Aspect_Dynamic_Predicate then Set_Has_Dynamic_Predicate_Aspect (Full_View (E)); elsif A_Id = Aspect_Static_Predicate then Set_Has_Static_Predicate_Aspect (Full_View (E)); end if; Set_Has_Delayed_Aspects (Full_View (E)); Ensure_Freeze_Node (Full_View (E)); end if; -- Predicate_Failure when Aspect_Predicate_Failure => -- This aspect applies only to subtypes if not Is_Type (E) then Error_Msg_N ("predicate can only be specified for a subtype", Aspect); goto Continue; elsif Is_Incomplete_Type (E) then Error_Msg_N ("predicate cannot apply to incomplete view", Aspect); goto Continue; end if; -- Construct the pragma Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Sloc (Ent), Expression => Ent), Make_Pragma_Argument_Association (Sloc (Expr), Expression => Relocate_Node (Expr))), Pragma_Name => Name_Predicate_Failure); Set_Has_Predicates (E); -- If the type is private, indicate that its completion -- has a freeze node, because that is the one that will -- be visible at freeze time. if Is_Private_Type (E) and then Present (Full_View (E)) then Set_Has_Predicates (Full_View (E)); Set_Has_Delayed_Aspects (Full_View (E)); Ensure_Freeze_Node (Full_View (E)); end if; -- Case 2b: Aspects corresponding to pragmas with two -- arguments, where the second argument is a local name -- referring to the entity, and the first argument is the -- aspect definition expression. -- Convention when Aspect_Convention => Analyze_Aspect_Convention; goto Continue; -- External_Name, Link_Name when Aspect_External_Name | Aspect_Link_Name => Analyze_Aspect_External_Link_Name; goto Continue; -- CPU, Interrupt_Priority, Priority -- These three aspects can be specified for a subprogram spec -- or body, in which case we analyze the expression and export -- the value of the aspect. -- Previously, we generated an equivalent pragma for bodies -- (note that the specs cannot contain these pragmas). The -- pragma was inserted ahead of local declarations, rather than -- after the body. This leads to a certain duplication between -- the processing performed for the aspect and the pragma, but -- given the straightforward handling required it is simpler -- to duplicate than to translate the aspect in the spec into -- a pragma in the declarative part of the body. when Aspect_CPU | Aspect_Interrupt_Priority | Aspect_Priority => if Nkind_In (N, N_Subprogram_Body, N_Subprogram_Declaration) then -- Analyze the aspect expression Analyze_And_Resolve (Expr, Standard_Integer); -- Interrupt_Priority aspect not allowed for main -- subprograms. RM D.1 does not forbid this explicitly, -- but RM J.15.11(6/3) does not permit pragma -- Interrupt_Priority for subprograms. if A_Id = Aspect_Interrupt_Priority then Error_Msg_N ("Interrupt_Priority aspect cannot apply to " & "subprogram", Expr); -- The expression must be static elsif not Is_OK_Static_Expression (Expr) then Flag_Non_Static_Expr ("aspect requires static expression!", Expr); -- Check whether this is the main subprogram. Issue a -- warning only if it is obviously not a main program -- (when it has parameters or when the subprogram is -- within a package). elsif Present (Parameter_Specifications (Specification (N))) or else not Is_Compilation_Unit (Defining_Entity (N)) then -- See RM D.1(14/3) and D.16(12/3) Error_Msg_N ("aspect applied to subprogram other than the " & "main subprogram has no effect??", Expr); -- Otherwise check in range and export the value -- For the CPU aspect elsif A_Id = Aspect_CPU then if Is_In_Range (Expr, RTE (RE_CPU_Range)) then -- Value is correct so we export the value to make -- it available at execution time. Set_Main_CPU (Main_Unit, UI_To_Int (Expr_Value (Expr))); else Error_Msg_N ("main subprogram CPU is out of range", Expr); end if; -- For the Priority aspect elsif A_Id = Aspect_Priority then if Is_In_Range (Expr, RTE (RE_Priority)) then -- Value is correct so we export the value to make -- it available at execution time. Set_Main_Priority (Main_Unit, UI_To_Int (Expr_Value (Expr))); -- Ignore pragma if Relaxed_RM_Semantics to support -- other targets/non GNAT compilers. elsif not Relaxed_RM_Semantics then Error_Msg_N ("main subprogram priority is out of range", Expr); end if; end if; -- Load an arbitrary entity from System.Tasking.Stages -- or System.Tasking.Restricted.Stages (depending on -- the supported profile) to make sure that one of these -- packages is implicitly with'ed, since we need to have -- the tasking run time active for the pragma Priority to -- have any effect. Previously we with'ed the package -- System.Tasking, but this package does not trigger the -- required initialization of the run-time library. declare Discard : Entity_Id; begin if Restricted_Profile then Discard := RTE (RE_Activate_Restricted_Tasks); else Discard := RTE (RE_Activate_Tasks); end if; end; -- Handling for these Aspects in subprograms is complete goto Continue; -- For tasks pass the aspect as an attribute else Aitem := Make_Attribute_Definition_Clause (Loc, Name => Ent, Chars => Chars (Id), Expression => Relocate_Node (Expr)); end if; -- Warnings when Aspect_Warnings => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Sloc (Expr), Expression => Relocate_Node (Expr)), Make_Pragma_Argument_Association (Loc, Expression => New_Occurrence_Of (E, Loc))), Pragma_Name => Chars (Id)); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Case 2c: Aspects corresponding to pragmas with three -- arguments. -- Invariant aspects have a first argument that references the -- entity, a second argument that is the expression and a third -- argument that is an appropriate message. -- Invariant, Type_Invariant when Aspect_Invariant | Aspect_Type_Invariant => -- Analysis of the pragma will verify placement legality: -- an invariant must apply to a private type, or appear in -- the private part of a spec and apply to a completion. Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Sloc (Ent), Expression => Ent), Make_Pragma_Argument_Association (Sloc (Expr), Expression => Relocate_Node (Expr))), Pragma_Name => Name_Invariant); -- Add message unless exception messages are suppressed if not Opt.Exception_Locations_Suppressed then Append_To (Pragma_Argument_Associations (Aitem), Make_Pragma_Argument_Association (Eloc, Chars => Name_Message, Expression => Make_String_Literal (Eloc, Strval => "failed invariant from " & Build_Location_String (Eloc)))); end if; -- For Invariant case, insert immediately after the entity -- declaration. We do not have to worry about delay issues -- since the pragma processing takes care of this. Delay_Required := False; -- Case 2d : Aspects that correspond to a pragma with one -- argument. -- Abstract_State -- Aspect Abstract_State introduces implicit declarations for -- all state abstraction entities it defines. To emulate this -- behavior, insert the pragma at the beginning of the visible -- declarations of the related package so that it is analyzed -- immediately. when Aspect_Abstract_State => Abstract_State : declare Context : Node_Id := N; begin -- When aspect Abstract_State appears on a generic package, -- it is propageted to the package instance. The context in -- this case is the instance spec. if Nkind (Context) = N_Package_Instantiation then Context := Instance_Spec (Context); end if; if Nkind_In (Context, N_Generic_Package_Declaration, N_Package_Declaration) then Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Abstract_State); Decorate (Aspect, Aitem); Insert_Pragma (Prag => Aitem, Is_Instance => Is_Generic_Instance (Defining_Entity (Context))); else Error_Msg_NE ("aspect & must apply to a package declaration", Aspect, Id); end if; goto Continue; end Abstract_State; -- Aspect Async_Readers is never delayed because it is -- equivalent to a source pragma which appears after the -- related object declaration. when Aspect_Async_Readers => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Async_Readers); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Aspect Async_Writers is never delayed because it is -- equivalent to a source pragma which appears after the -- related object declaration. when Aspect_Async_Writers => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Async_Writers); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Aspect Constant_After_Elaboration is never delayed because -- it is equivalent to a source pragma which appears after the -- related object declaration. when Aspect_Constant_After_Elaboration => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Constant_After_Elaboration); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Aspect Default_Internal_Condition is never delayed because -- it is equivalent to a source pragma which appears after the -- related private type. To deal with forward references, the -- generated pragma is stored in the rep chain of the related -- private type as types do not carry contracts. The pragma is -- wrapped inside of a procedure at the freeze point of the -- private type's full view. when Aspect_Default_Initial_Condition => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Default_Initial_Condition); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Default_Storage_Pool when Aspect_Default_Storage_Pool => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Default_Storage_Pool); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Depends -- Aspect Depends is never delayed because it is equivalent to -- a source pragma which appears after the related subprogram. -- To deal with forward references, the generated pragma is -- stored in the contract of the related subprogram and later -- analyzed at the end of the declarative region. See routine -- Analyze_Depends_In_Decl_Part for details. when Aspect_Depends => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Depends); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Aspect Effecitve_Reads is never delayed because it is -- equivalent to a source pragma which appears after the -- related object declaration. when Aspect_Effective_Reads => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Effective_Reads); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Aspect Effective_Writes is never delayed because it is -- equivalent to a source pragma which appears after the -- related object declaration. when Aspect_Effective_Writes => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Effective_Writes); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Aspect Extensions_Visible is never delayed because it is -- equivalent to a source pragma which appears after the -- related subprogram. when Aspect_Extensions_Visible => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Extensions_Visible); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Aspect Ghost is never delayed because it is equivalent to a -- source pragma which appears at the top of [generic] package -- declarations or after an object, a [generic] subprogram, or -- a type declaration. when Aspect_Ghost => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Ghost); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Global -- Aspect Global is never delayed because it is equivalent to -- a source pragma which appears after the related subprogram. -- To deal with forward references, the generated pragma is -- stored in the contract of the related subprogram and later -- analyzed at the end of the declarative region. See routine -- Analyze_Global_In_Decl_Part for details. when Aspect_Global => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Global); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Initial_Condition -- Aspect Initial_Condition is never delayed because it is -- equivalent to a source pragma which appears after the -- related package. To deal with forward references, the -- generated pragma is stored in the contract of the related -- package and later analyzed at the end of the declarative -- region. See routine Analyze_Initial_Condition_In_Decl_Part -- for details. when Aspect_Initial_Condition => Initial_Condition : declare Context : Node_Id := N; begin -- When aspect Initial_Condition appears on a generic -- package, it is propageted to the package instance. The -- context in this case is the instance spec. if Nkind (Context) = N_Package_Instantiation then Context := Instance_Spec (Context); end if; if Nkind_In (Context, N_Generic_Package_Declaration, N_Package_Declaration) then Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Initial_Condition); Decorate (Aspect, Aitem); Insert_Pragma (Prag => Aitem, Is_Instance => Is_Generic_Instance (Defining_Entity (Context))); -- Otherwise the context is illegal else Error_Msg_NE ("aspect & must apply to a package declaration", Aspect, Id); end if; goto Continue; end Initial_Condition; -- Initializes -- Aspect Initializes is never delayed because it is equivalent -- to a source pragma appearing after the related package. To -- deal with forward references, the generated pragma is stored -- in the contract of the related package and later analyzed at -- the end of the declarative region. For details, see routine -- Analyze_Initializes_In_Decl_Part. when Aspect_Initializes => Initializes : declare Context : Node_Id := N; begin -- When aspect Initializes appears on a generic package, -- it is propageted to the package instance. The context -- in this case is the instance spec. if Nkind (Context) = N_Package_Instantiation then Context := Instance_Spec (Context); end if; if Nkind_In (Context, N_Generic_Package_Declaration, N_Package_Declaration) then Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Initializes); Decorate (Aspect, Aitem); Insert_Pragma (Prag => Aitem, Is_Instance => Is_Generic_Instance (Defining_Entity (Context))); -- Otherwise the context is illegal else Error_Msg_NE ("aspect & must apply to a package declaration", Aspect, Id); end if; goto Continue; end Initializes; -- Obsolescent when Aspect_Obsolescent => declare Args : List_Id; begin if No (Expr) then Args := No_List; else Args := New_List ( Make_Pragma_Argument_Association (Sloc (Expr), Expression => Relocate_Node (Expr))); end if; Make_Aitem_Pragma (Pragma_Argument_Associations => Args, Pragma_Name => Chars (Id)); end; -- Part_Of when Aspect_Part_Of => if Nkind_In (N, N_Object_Declaration, N_Package_Instantiation) or else Is_Single_Concurrent_Type_Declaration (N) then Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Part_Of); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); else Error_Msg_NE ("aspect & must apply to package instantiation, " & "object, single protected type or single task type", Aspect, Id); end if; goto Continue; -- SPARK_Mode when Aspect_SPARK_Mode => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_SPARK_Mode); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Refined_Depends -- Aspect Refined_Depends is never delayed because it is -- equivalent to a source pragma which appears in the -- declarations of the related subprogram body. To deal with -- forward references, the generated pragma is stored in the -- contract of the related subprogram body and later analyzed -- at the end of the declarative region. For details, see -- routine Analyze_Refined_Depends_In_Decl_Part. when Aspect_Refined_Depends => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Refined_Depends); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Refined_Global -- Aspect Refined_Global is never delayed because it is -- equivalent to a source pragma which appears in the -- declarations of the related subprogram body. To deal with -- forward references, the generated pragma is stored in the -- contract of the related subprogram body and later analyzed -- at the end of the declarative region. For details, see -- routine Analyze_Refined_Global_In_Decl_Part. when Aspect_Refined_Global => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Refined_Global); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Refined_Post when Aspect_Refined_Post => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Refined_Post); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Refined_State when Aspect_Refined_State => -- The corresponding pragma for Refined_State is inserted in -- the declarations of the related package body. This action -- synchronizes both the source and from-aspect versions of -- the pragma. if Nkind (N) = N_Package_Body then Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Refined_State); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); -- Otherwise the context is illegal else Error_Msg_NE ("aspect & must apply to a package body", Aspect, Id); end if; goto Continue; -- Relative_Deadline when Aspect_Relative_Deadline => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Relative_Deadline); -- If the aspect applies to a task, the corresponding pragma -- must appear within its declarations, not after. if Nkind (N) = N_Task_Type_Declaration then declare Def : Node_Id; V : List_Id; begin if No (Task_Definition (N)) then Set_Task_Definition (N, Make_Task_Definition (Loc, Visible_Declarations => New_List, End_Label => Empty)); end if; Def := Task_Definition (N); V := Visible_Declarations (Def); if not Is_Empty_List (V) then Insert_Before (First (V), Aitem); else Set_Visible_Declarations (Def, New_List (Aitem)); end if; goto Continue; end; end if; -- Aspect Volatile_Function is never delayed because it is -- equivalent to a source pragma which appears after the -- related subprogram. when Aspect_Volatile_Function => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Volatile_Function); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Case 2e: Annotate aspect when Aspect_Annotate => declare Args : List_Id; Pargs : List_Id; Arg : Node_Id; begin -- The argument can be a single identifier if Nkind (Expr) = N_Identifier then -- One level of parens is allowed if Paren_Count (Expr) > 1 then Error_Msg_F ("extra parentheses ignored", Expr); end if; Set_Paren_Count (Expr, 0); -- Add the single item to the list Args := New_List (Expr); -- Otherwise we must have an aggregate elsif Nkind (Expr) = N_Aggregate then -- Must be positional if Present (Component_Associations (Expr)) then Error_Msg_F ("purely positional aggregate required", Expr); goto Continue; end if; -- Must not be parenthesized if Paren_Count (Expr) /= 0 then Error_Msg_F ("extra parentheses ignored", Expr); end if; -- List of arguments is list of aggregate expressions Args := Expressions (Expr); -- Anything else is illegal else Error_Msg_F ("wrong form for Annotate aspect", Expr); goto Continue; end if; -- Prepare pragma arguments Pargs := New_List; Arg := First (Args); while Present (Arg) loop Append_To (Pargs, Make_Pragma_Argument_Association (Sloc (Arg), Expression => Relocate_Node (Arg))); Next (Arg); end loop; Append_To (Pargs, Make_Pragma_Argument_Association (Sloc (Ent), Chars => Name_Entity, Expression => Ent)); Make_Aitem_Pragma (Pragma_Argument_Associations => Pargs, Pragma_Name => Name_Annotate); end; -- Case 3 : Aspects that don't correspond to pragma/attribute -- definition clause. -- Case 3a: The aspects listed below don't correspond to -- pragmas/attributes but do require delayed analysis. -- Default_Value can only apply to a scalar type when Aspect_Default_Value => if not Is_Scalar_Type (E) then Error_Msg_N ("aspect Default_Value must apply to a scalar type", N); end if; Aitem := Empty; -- Default_Component_Value can only apply to an array type -- with scalar components. when Aspect_Default_Component_Value => if not (Is_Array_Type (E) and then Is_Scalar_Type (Component_Type (E))) then Error_Msg_N ("aspect Default_Component_Value can only apply to an " & "array of scalar components", N); end if; Aitem := Empty; -- Case 3b: The aspects listed below don't correspond to -- pragmas/attributes and don't need delayed analysis. -- Implicit_Dereference -- For Implicit_Dereference, External_Name and Link_Name, only -- the legality checks are done during the analysis, thus no -- delay is required. when Aspect_Implicit_Dereference => Analyze_Aspect_Implicit_Dereference; goto Continue; -- Dimension when Aspect_Dimension => Analyze_Aspect_Dimension (N, Id, Expr); goto Continue; -- Dimension_System when Aspect_Dimension_System => Analyze_Aspect_Dimension_System (N, Id, Expr); goto Continue; -- Case 4: Aspects requiring special handling -- Pre/Post/Test_Case/Contract_Cases whose corresponding -- pragmas take care of the delay. -- Pre/Post -- Aspects Pre/Post generate Precondition/Postcondition pragmas -- with a first argument that is the expression, and a second -- argument that is an informative message if the test fails. -- This is inserted right after the declaration, to get the -- required pragma placement. The processing for the pragmas -- takes care of the required delay. when Pre_Post_Aspects => Pre_Post : declare Pname : Name_Id; begin if A_Id = Aspect_Pre or else A_Id = Aspect_Precondition then Pname := Name_Precondition; else Pname := Name_Postcondition; end if; -- Check that the class-wide predicate cannot be applied to -- an operation of a synchronized type that is not a tagged -- type. Other legality checks are performed when analyzing -- the contract of the operation. if Class_Present (Aspect) and then Is_Concurrent_Type (Current_Scope) and then not Is_Tagged_Type (Current_Scope) and then Ekind_In (E, E_Entry, E_Function, E_Procedure) then Error_Msg_Name_1 := Original_Aspect_Pragma_Name (Aspect); Error_Msg_N ("aspect % can only be specified for a primitive " & "operation of a tagged type", Aspect); goto Continue; end if; -- If the expressions is of the form A and then B, then -- we generate separate Pre/Post aspects for the separate -- clauses. Since we allow multiple pragmas, there is no -- problem in allowing multiple Pre/Post aspects internally. -- These should be treated in reverse order (B first and -- A second) since they are later inserted just after N in -- the order they are treated. This way, the pragma for A -- ends up preceding the pragma for B, which may have an -- importance for the error raised (either constraint error -- or precondition error). -- We do not do this for Pre'Class, since we have to put -- these conditions together in a complex OR expression. -- We do not do this in ASIS mode, as ASIS relies on the -- original node representing the complete expression, when -- retrieving it through the source aspect table. if not ASIS_Mode and then (Pname = Name_Postcondition or else not Class_Present (Aspect)) then while Nkind (Expr) = N_And_Then loop Insert_After (Aspect, Make_Aspect_Specification (Sloc (Left_Opnd (Expr)), Identifier => Identifier (Aspect), Expression => Relocate_Node (Left_Opnd (Expr)), Class_Present => Class_Present (Aspect), Split_PPC => True)); Rewrite (Expr, Relocate_Node (Right_Opnd (Expr))); Eloc := Sloc (Expr); end loop; end if; -- Build the precondition/postcondition pragma -- Add note about why we do NOT need Copy_Tree here??? Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Eloc, Chars => Name_Check, Expression => Relocate_Node (Expr))), Pragma_Name => Pname); -- Add message unless exception messages are suppressed if not Opt.Exception_Locations_Suppressed then Append_To (Pragma_Argument_Associations (Aitem), Make_Pragma_Argument_Association (Eloc, Chars => Name_Message, Expression => Make_String_Literal (Eloc, Strval => "failed " & Get_Name_String (Pname) & " from " & Build_Location_String (Eloc)))); end if; Set_Is_Delayed_Aspect (Aspect); -- For Pre/Post cases, insert immediately after the entity -- declaration, since that is the required pragma placement. -- Note that for these aspects, we do not have to worry -- about delay issues, since the pragmas themselves deal -- with delay of visibility for the expression analysis. Insert_Pragma (Aitem); goto Continue; end Pre_Post; -- Test_Case when Aspect_Test_Case => Test_Case : declare Args : List_Id; Comp_Expr : Node_Id; Comp_Assn : Node_Id; New_Expr : Node_Id; begin Args := New_List; if Nkind (Parent (N)) = N_Compilation_Unit then Error_Msg_Name_1 := Nam; Error_Msg_N ("incorrect placement of aspect `%`", E); goto Continue; end if; if Nkind (Expr) /= N_Aggregate then Error_Msg_Name_1 := Nam; Error_Msg_NE ("wrong syntax for aspect `%` for &", Id, E); goto Continue; end if; -- Make pragma expressions refer to the original aspect -- expressions through the Original_Node link. This is used -- in semantic analysis for ASIS mode, so that the original -- expression also gets analyzed. Comp_Expr := First (Expressions (Expr)); while Present (Comp_Expr) loop New_Expr := Relocate_Node (Comp_Expr); Append_To (Args, Make_Pragma_Argument_Association (Sloc (Comp_Expr), Expression => New_Expr)); Next (Comp_Expr); end loop; Comp_Assn := First (Component_Associations (Expr)); while Present (Comp_Assn) loop if List_Length (Choices (Comp_Assn)) /= 1 or else Nkind (First (Choices (Comp_Assn))) /= N_Identifier then Error_Msg_Name_1 := Nam; Error_Msg_NE ("wrong syntax for aspect `%` for &", Id, E); goto Continue; end if; Append_To (Args, Make_Pragma_Argument_Association (Sloc (Comp_Assn), Chars => Chars (First (Choices (Comp_Assn))), Expression => Relocate_Node (Expression (Comp_Assn)))); Next (Comp_Assn); end loop; -- Build the test-case pragma Make_Aitem_Pragma (Pragma_Argument_Associations => Args, Pragma_Name => Nam); end Test_Case; -- Contract_Cases when Aspect_Contract_Cases => Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Nam); Decorate (Aspect, Aitem); Insert_Pragma (Aitem); goto Continue; -- Case 5: Special handling for aspects with an optional -- boolean argument. -- In the delayed case, the corresponding pragma cannot be -- generated yet because the evaluation of the boolean needs -- to be delayed till the freeze point. when Boolean_Aspects | Library_Unit_Aspects => Set_Is_Boolean_Aspect (Aspect); -- Lock_Free aspect only apply to protected objects if A_Id = Aspect_Lock_Free then if Ekind (E) /= E_Protected_Type then Error_Msg_Name_1 := Nam; Error_Msg_N ("aspect % only applies to a protected object", Aspect); else -- Set the Uses_Lock_Free flag to True if there is no -- expression or if the expression is True. The -- evaluation of this aspect should be delayed to the -- freeze point (why???) if No (Expr) or else Is_True (Static_Boolean (Expr)) then Set_Uses_Lock_Free (E); end if; Record_Rep_Item (E, Aspect); end if; goto Continue; elsif A_Id = Aspect_Export or else A_Id = Aspect_Import then Analyze_Aspect_Export_Import; -- Disable_Controlled elsif A_Id = Aspect_Disable_Controlled then if Ekind (E) /= E_Record_Type or else not Is_Controlled (E) then Error_Msg_N ("aspect % requires controlled record type", Aspect); goto Continue; end if; -- If we're in a generic template, we don't want to try -- to disable controlled types, because typical usage is -- "Disable_Controlled => not 'Enabled", and -- the value of Enabled is not known until we see a -- particular instance. In such a context, we just need -- to preanalyze the expression for legality. if Expander_Active then Analyze_And_Resolve (Expr, Standard_Boolean); if not Present (Expr) or else Is_True (Static_Boolean (Expr)) then Set_Disable_Controlled (E); end if; elsif Serious_Errors_Detected = 0 then Preanalyze_And_Resolve (Expr, Standard_Boolean); end if; goto Continue; end if; -- Library unit aspects require special handling in the case -- of a package declaration, the pragma needs to be inserted -- in the list of declarations for the associated package. -- There is no issue of visibility delay for these aspects. if A_Id in Library_Unit_Aspects and then Nkind_In (N, N_Package_Declaration, N_Generic_Package_Declaration) and then Nkind (Parent (N)) /= N_Compilation_Unit -- Aspect is legal on a local instantiation of a library- -- level generic unit. and then not Is_Generic_Instance (Defining_Entity (N)) then Error_Msg_N ("incorrect context for library unit aspect&", Id); goto Continue; end if; -- Cases where we do not delay, includes all cases where the -- expression is missing other than the above cases. if not Delay_Required or else No (Expr) then -- Exclude aspects Export and Import because their pragma -- syntax does not map directly to a Boolean aspect. if A_Id /= Aspect_Export and then A_Id /= Aspect_Import then Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Sloc (Ent), Expression => Ent)), Pragma_Name => Chars (Id)); end if; Delay_Required := False; -- In general cases, the corresponding pragma/attribute -- definition clause will be inserted later at the freezing -- point, and we do not need to build it now. else Aitem := Empty; end if; -- Storage_Size -- This is special because for access types we need to generate -- an attribute definition clause. This also works for single -- task declarations, but it does not work for task type -- declarations, because we have the case where the expression -- references a discriminant of the task type. That can't use -- an attribute definition clause because we would not have -- visibility on the discriminant. For that case we must -- generate a pragma in the task definition. when Aspect_Storage_Size => -- Task type case if Ekind (E) = E_Task_Type then declare Decl : constant Node_Id := Declaration_Node (E); begin pragma Assert (Nkind (Decl) = N_Task_Type_Declaration); -- If no task definition, create one if No (Task_Definition (Decl)) then Set_Task_Definition (Decl, Make_Task_Definition (Loc, Visible_Declarations => Empty_List, End_Label => Empty)); end if; -- Create a pragma and put it at the start of the task -- definition for the task type declaration. Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Loc, Expression => Relocate_Node (Expr))), Pragma_Name => Name_Storage_Size); Prepend (Aitem, Visible_Declarations (Task_Definition (Decl))); goto Continue; end; -- All other cases, generate attribute definition else Aitem := Make_Attribute_Definition_Clause (Loc, Name => Ent, Chars => Chars (Id), Expression => Relocate_Node (Expr)); end if; end case; -- Attach the corresponding pragma/attribute definition clause to -- the aspect specification node. if Present (Aitem) then Set_From_Aspect_Specification (Aitem); end if; -- In the context of a compilation unit, we directly put the -- pragma in the Pragmas_After list of the N_Compilation_Unit_Aux -- node (no delay is required here) except for aspects on a -- subprogram body (see below) and a generic package, for which we -- need to introduce the pragma before building the generic copy -- (see sem_ch12), and for package instantiations, where the -- library unit pragmas are better handled early. if Nkind (Parent (N)) = N_Compilation_Unit and then (Present (Aitem) or else Is_Boolean_Aspect (Aspect)) then declare Aux : constant Node_Id := Aux_Decls_Node (Parent (N)); begin pragma Assert (Nkind (Aux) = N_Compilation_Unit_Aux); -- For a Boolean aspect, create the corresponding pragma if -- no expression or if the value is True. if Is_Boolean_Aspect (Aspect) and then No (Aitem) then if Is_True (Static_Boolean (Expr)) then Make_Aitem_Pragma (Pragma_Argument_Associations => New_List ( Make_Pragma_Argument_Association (Sloc (Ent), Expression => Ent)), Pragma_Name => Chars (Id)); Set_From_Aspect_Specification (Aitem, True); Set_Corresponding_Aspect (Aitem, Aspect); else goto Continue; end if; end if; -- If the aspect is on a subprogram body (relevant aspect -- is Inline), add the pragma in front of the declarations. if Nkind (N) = N_Subprogram_Body then if No (Declarations (N)) then Set_Declarations (N, New_List); end if; Prepend (Aitem, Declarations (N)); elsif Nkind (N) = N_Generic_Package_Declaration then if No (Visible_Declarations (Specification (N))) then Set_Visible_Declarations (Specification (N), New_List); end if; Prepend (Aitem, Visible_Declarations (Specification (N))); elsif Nkind (N) = N_Package_Instantiation then declare Spec : constant Node_Id := Specification (Instance_Spec (N)); begin if No (Visible_Declarations (Spec)) then Set_Visible_Declarations (Spec, New_List); end if; Prepend (Aitem, Visible_Declarations (Spec)); end; else if No (Pragmas_After (Aux)) then Set_Pragmas_After (Aux, New_List); end if; Append (Aitem, Pragmas_After (Aux)); end if; goto Continue; end; end if; -- The evaluation of the aspect is delayed to the freezing point. -- The pragma or attribute clause if there is one is then attached -- to the aspect specification which is put in the rep item list. if Delay_Required then if Present (Aitem) then Set_Is_Delayed_Aspect (Aitem); Set_Aspect_Rep_Item (Aspect, Aitem); Set_Parent (Aitem, Aspect); end if; Set_Is_Delayed_Aspect (Aspect); -- In the case of Default_Value, link the aspect to base type -- as well, even though it appears on a first subtype. This is -- mandated by the semantics of the aspect. Do not establish -- the link when processing the base type itself as this leads -- to a rep item circularity. Verify that we are dealing with -- a scalar type to prevent cascaded errors. if A_Id = Aspect_Default_Value and then Is_Scalar_Type (E) and then Base_Type (E) /= E then Set_Has_Delayed_Aspects (Base_Type (E)); Record_Rep_Item (Base_Type (E), Aspect); end if; Set_Has_Delayed_Aspects (E); Record_Rep_Item (E, Aspect); -- When delay is not required and the context is a package or a -- subprogram body, insert the pragma in the body declarations. elsif Nkind_In (N, N_Package_Body, N_Subprogram_Body) then if No (Declarations (N)) then Set_Declarations (N, New_List); end if; -- The pragma is added before source declarations Prepend_To (Declarations (N), Aitem); -- When delay is not required and the context is not a compilation -- unit, we simply insert the pragma/attribute definition clause -- in sequence. elsif Present (Aitem) then Insert_After (Ins_Node, Aitem); Ins_Node := Aitem; end if; end Analyze_One_Aspect; <> Next (Aspect); end loop Aspect_Loop; if Has_Delayed_Aspects (E) then Ensure_Freeze_Node (E); end if; end Analyze_Aspect_Specifications; --------------------------------------------------- -- Analyze_Aspect_Specifications_On_Body_Or_Stub -- --------------------------------------------------- procedure Analyze_Aspect_Specifications_On_Body_Or_Stub (N : Node_Id) is Body_Id : constant Entity_Id := Defining_Entity (N); procedure Diagnose_Misplaced_Aspects (Spec_Id : Entity_Id); -- Body [stub] N has aspects, but they are not properly placed. Emit an -- error message depending on the aspects involved. Spec_Id denotes the -- entity of the corresponding spec. -------------------------------- -- Diagnose_Misplaced_Aspects -- -------------------------------- procedure Diagnose_Misplaced_Aspects (Spec_Id : Entity_Id) is procedure Misplaced_Aspect_Error (Asp : Node_Id; Ref_Nam : Name_Id); -- Emit an error message concerning misplaced aspect Asp. Ref_Nam is -- the name of the refined version of the aspect. ---------------------------- -- Misplaced_Aspect_Error -- ---------------------------- procedure Misplaced_Aspect_Error (Asp : Node_Id; Ref_Nam : Name_Id) is Asp_Nam : constant Name_Id := Chars (Identifier (Asp)); Asp_Id : constant Aspect_Id := Get_Aspect_Id (Asp_Nam); begin -- The corresponding spec already contains the aspect in question -- and the one appearing on the body must be the refined form: -- procedure P with Global ...; -- procedure P with Global ... is ... end P; -- ^ -- Refined_Global if Has_Aspect (Spec_Id, Asp_Id) then Error_Msg_Name_1 := Asp_Nam; -- Subunits cannot carry aspects that apply to a subprogram -- declaration. if Nkind (Parent (N)) = N_Subunit then Error_Msg_N ("aspect % cannot apply to a subunit", Asp); -- Otherwise suggest the refined form else Error_Msg_Name_2 := Ref_Nam; Error_Msg_N ("aspect % should be %", Asp); end if; -- Otherwise the aspect must appear on the spec, not on the body -- procedure P; -- procedure P with Global ... is ... end P; else Error_Msg_N ("aspect specification must appear on initial declaration", Asp); end if; end Misplaced_Aspect_Error; -- Local variables Asp : Node_Id; Asp_Nam : Name_Id; -- Start of processing for Diagnose_Misplaced_Aspects begin -- Iterate over the aspect specifications and emit specific errors -- where applicable. Asp := First (Aspect_Specifications (N)); while Present (Asp) loop Asp_Nam := Chars (Identifier (Asp)); -- Do not emit errors on aspects that can appear on a subprogram -- body. This scenario occurs when the aspect specification list -- contains both misplaced and properly placed aspects. if Aspect_On_Body_Or_Stub_OK (Get_Aspect_Id (Asp_Nam)) then null; -- Special diagnostics for SPARK aspects elsif Asp_Nam = Name_Depends then Misplaced_Aspect_Error (Asp, Name_Refined_Depends); elsif Asp_Nam = Name_Global then Misplaced_Aspect_Error (Asp, Name_Refined_Global); elsif Asp_Nam = Name_Post then Misplaced_Aspect_Error (Asp, Name_Refined_Post); -- Otherwise a language-defined aspect is misplaced else Error_Msg_N ("aspect specification must appear on initial declaration", Asp); end if; Next (Asp); end loop; end Diagnose_Misplaced_Aspects; -- Local variables Spec_Id : constant Entity_Id := Unique_Defining_Entity (N); -- Start of processing for Analyze_Aspects_On_Body_Or_Stub begin -- Language-defined aspects cannot be associated with a subprogram body -- [stub] if the subprogram has a spec. Certain implementation defined -- aspects are allowed to break this rule (for all applicable cases, see -- table Aspects.Aspect_On_Body_Or_Stub_OK). if Spec_Id /= Body_Id and then not Aspects_On_Body_Or_Stub_OK (N) then Diagnose_Misplaced_Aspects (Spec_Id); else Analyze_Aspect_Specifications (N, Body_Id); end if; end Analyze_Aspect_Specifications_On_Body_Or_Stub; ----------------------- -- Analyze_At_Clause -- ----------------------- -- An at clause is replaced by the corresponding Address attribute -- definition clause that is the preferred approach in Ada 95. procedure Analyze_At_Clause (N : Node_Id) is CS : constant Boolean := Comes_From_Source (N); begin -- This is an obsolescent feature Check_Restriction (No_Obsolescent_Features, N); if Warn_On_Obsolescent_Feature then Error_Msg_N ("?j?at clause is an obsolescent feature (RM J.7(2))", N); Error_Msg_N ("\?j?use address attribute definition clause instead", N); end if; -- Rewrite as address clause Rewrite (N, Make_Attribute_Definition_Clause (Sloc (N), Name => Identifier (N), Chars => Name_Address, Expression => Expression (N))); -- We preserve Comes_From_Source, since logically the clause still comes -- from the source program even though it is changed in form. Set_Comes_From_Source (N, CS); -- Analyze rewritten clause Analyze_Attribute_Definition_Clause (N); end Analyze_At_Clause; ----------------------------------------- -- Analyze_Attribute_Definition_Clause -- ----------------------------------------- procedure Analyze_Attribute_Definition_Clause (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Nam : constant Node_Id := Name (N); Attr : constant Name_Id := Chars (N); Expr : constant Node_Id := Expression (N); Id : constant Attribute_Id := Get_Attribute_Id (Attr); Ent : Entity_Id; -- The entity of Nam after it is analyzed. In the case of an incomplete -- type, this is the underlying type. U_Ent : Entity_Id; -- The underlying entity to which the attribute applies. Generally this -- is the Underlying_Type of Ent, except in the case where the clause -- applies to the full view of an incomplete or private type, in which -- case U_Ent is just a copy of Ent. FOnly : Boolean := False; -- Reset to True for subtype specific attribute (Alignment, Size) -- and for stream attributes, i.e. those cases where in the call to -- Rep_Item_Too_Late, FOnly is set True so that only the freezing rules -- are checked. Note that the case of stream attributes is not clear -- from the RM, but see AI95-00137. Also, the RM seems to disallow -- Storage_Size for derived task types, but that is also clearly -- unintentional. procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type); -- Common processing for 'Read, 'Write, 'Input and 'Output attribute -- definition clauses. function Duplicate_Clause return Boolean; -- This routine checks if the aspect for U_Ent being given by attribute -- definition clause N is for an aspect that has already been specified, -- and if so gives an error message. If there is a duplicate, True is -- returned, otherwise if there is no error, False is returned. procedure Check_Indexing_Functions; -- Check that the function in Constant_Indexing or Variable_Indexing -- attribute has the proper type structure. If the name is overloaded, -- check that some interpretation is legal. procedure Check_Iterator_Functions; -- Check that there is a single function in Default_Iterator attribute -- has the proper type structure. function Check_Primitive_Function (Subp : Entity_Id) return Boolean; -- Common legality check for the previous two ----------------------------------- -- Analyze_Stream_TSS_Definition -- ----------------------------------- procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type) is Subp : Entity_Id := Empty; I : Interp_Index; It : Interp; Pnam : Entity_Id; Is_Read : constant Boolean := (TSS_Nam = TSS_Stream_Read); -- True for Read attribute, False for other attributes function Has_Good_Profile (Subp : Entity_Id; Report : Boolean := False) return Boolean; -- Return true if the entity is a subprogram with an appropriate -- profile for the attribute being defined. If result is False and -- Report is True, function emits appropriate error. ---------------------- -- Has_Good_Profile -- ---------------------- function Has_Good_Profile (Subp : Entity_Id; Report : Boolean := False) return Boolean is Expected_Ekind : constant array (Boolean) of Entity_Kind := (False => E_Procedure, True => E_Function); Is_Function : constant Boolean := (TSS_Nam = TSS_Stream_Input); F : Entity_Id; Typ : Entity_Id; begin if Ekind (Subp) /= Expected_Ekind (Is_Function) then return False; end if; F := First_Formal (Subp); if No (F) or else Ekind (Etype (F)) /= E_Anonymous_Access_Type or else Designated_Type (Etype (F)) /= Class_Wide_Type (RTE (RE_Root_Stream_Type)) then return False; end if; if not Is_Function then Next_Formal (F); declare Expected_Mode : constant array (Boolean) of Entity_Kind := (False => E_In_Parameter, True => E_Out_Parameter); begin if Parameter_Mode (F) /= Expected_Mode (Is_Read) then return False; end if; end; Typ := Etype (F); -- If the attribute specification comes from an aspect -- specification for a class-wide stream, the parameter must be -- a class-wide type of the entity to which the aspect applies. if From_Aspect_Specification (N) and then Class_Present (Parent (N)) and then Is_Class_Wide_Type (Typ) then Typ := Etype (Typ); end if; else Typ := Etype (Subp); end if; -- Verify that the prefix of the attribute and the local name for -- the type of the formal match, or one is the class-wide of the -- other, in the case of a class-wide stream operation. if Base_Type (Typ) = Base_Type (Ent) or else (Is_Class_Wide_Type (Typ) and then Typ = Class_Wide_Type (Base_Type (Ent))) or else (Is_Class_Wide_Type (Ent) and then Ent = Class_Wide_Type (Base_Type (Typ))) then null; else return False; end if; if Present (Next_Formal (F)) then return False; elsif not Is_Scalar_Type (Typ) and then not Is_First_Subtype (Typ) and then not Is_Class_Wide_Type (Typ) then if Report and not Is_First_Subtype (Typ) then Error_Msg_N ("subtype of formal in stream operation must be a first " & "subtype", Parameter_Type (Parent (F))); end if; return False; else return True; end if; end Has_Good_Profile; -- Start of processing for Analyze_Stream_TSS_Definition begin FOnly := True; if not Is_Type (U_Ent) then Error_Msg_N ("local name must be a subtype", Nam); return; elsif not Is_First_Subtype (U_Ent) then Error_Msg_N ("local name must be a first subtype", Nam); return; end if; Pnam := TSS (Base_Type (U_Ent), TSS_Nam); -- If Pnam is present, it can be either inherited from an ancestor -- type (in which case it is legal to redefine it for this type), or -- be a previous definition of the attribute for the same type (in -- which case it is illegal). -- In the first case, it will have been analyzed already, and we -- can check that its profile does not match the expected profile -- for a stream attribute of U_Ent. In the second case, either Pnam -- has been analyzed (and has the expected profile), or it has not -- been analyzed yet (case of a type that has not been frozen yet -- and for which the stream attribute has been set using Set_TSS). if Present (Pnam) and then (No (First_Entity (Pnam)) or else Has_Good_Profile (Pnam)) then Error_Msg_Sloc := Sloc (Pnam); Error_Msg_Name_1 := Attr; Error_Msg_N ("% attribute already defined #", Nam); return; end if; Analyze (Expr); if Is_Entity_Name (Expr) then if not Is_Overloaded (Expr) then if Has_Good_Profile (Entity (Expr), Report => True) then Subp := Entity (Expr); end if; else Get_First_Interp (Expr, I, It); while Present (It.Nam) loop if Has_Good_Profile (It.Nam) then Subp := It.Nam; exit; end if; Get_Next_Interp (I, It); end loop; end if; end if; if Present (Subp) then if Is_Abstract_Subprogram (Subp) then Error_Msg_N ("stream subprogram must not be abstract", Expr); return; -- A stream subprogram for an interface type must be a null -- procedure (RM 13.13.2 (38/3)). Note that the class-wide type -- of an interface is not an interface type (3.9.4 (6.b/2)). elsif Is_Interface (U_Ent) and then not Is_Class_Wide_Type (U_Ent) and then not Inside_A_Generic and then (Ekind (Subp) = E_Function or else not Null_Present (Specification (Unit_Declaration_Node (Ultimate_Alias (Subp))))) then Error_Msg_N ("stream subprogram for interface type must be null " & "procedure", Expr); end if; Set_Entity (Expr, Subp); Set_Etype (Expr, Etype (Subp)); New_Stream_Subprogram (N, U_Ent, Subp, TSS_Nam); else Error_Msg_Name_1 := Attr; Error_Msg_N ("incorrect expression for% attribute", Expr); end if; end Analyze_Stream_TSS_Definition; ------------------------------ -- Check_Indexing_Functions -- ------------------------------ procedure Check_Indexing_Functions is Indexing_Found : Boolean := False; procedure Check_Inherited_Indexing; -- For a derived type, check that no indexing aspect is specified -- for the type if it is also inherited procedure Check_One_Function (Subp : Entity_Id); -- Check one possible interpretation. Sets Indexing_Found True if a -- legal indexing function is found. procedure Illegal_Indexing (Msg : String); -- Diagnose illegal indexing function if not overloaded. In the -- overloaded case indicate that no legal interpretation exists. ------------------------------ -- Check_Inherited_Indexing -- ------------------------------ procedure Check_Inherited_Indexing is Inherited : Node_Id; begin if Attr = Name_Constant_Indexing then Inherited := Find_Aspect (Etype (Ent), Aspect_Constant_Indexing); else pragma Assert (Attr = Name_Variable_Indexing); Inherited := Find_Aspect (Etype (Ent), Aspect_Variable_Indexing); end if; if Present (Inherited) then if Debug_Flag_Dot_XX then null; -- OK if current attribute_definition_clause is expansion of -- inherited aspect. elsif Aspect_Rep_Item (Inherited) = N then null; -- Indicate the operation that must be overridden, rather than -- redefining the indexing aspect. else Illegal_Indexing ("indexing function already inherited from parent type"); Error_Msg_NE ("!override & instead", N, Entity (Expression (Inherited))); end if; end if; end Check_Inherited_Indexing; ------------------------ -- Check_One_Function -- ------------------------ procedure Check_One_Function (Subp : Entity_Id) is Default_Element : Node_Id; Ret_Type : constant Entity_Id := Etype (Subp); begin if not Is_Overloadable (Subp) then Illegal_Indexing ("illegal indexing function for type&"); return; elsif Scope (Subp) /= Scope (Ent) then if Nkind (Expr) = N_Expanded_Name then -- Indexing function can't be declared elsewhere Illegal_Indexing ("indexing function must be declared in scope of type&"); end if; return; elsif No (First_Formal (Subp)) then Illegal_Indexing ("Indexing requires a function that applies to type&"); return; elsif No (Next_Formal (First_Formal (Subp))) then Illegal_Indexing ("indexing function must have at least two parameters"); return; elsif Is_Derived_Type (Ent) then Check_Inherited_Indexing; end if; if not Check_Primitive_Function (Subp) then Illegal_Indexing ("Indexing aspect requires a function that applies to type&"); return; end if; -- If partial declaration exists, verify that it is not tagged. if Ekind (Current_Scope) = E_Package and then Has_Private_Declaration (Ent) and then From_Aspect_Specification (N) and then List_Containing (Parent (Ent)) = Private_Declarations (Specification (Unit_Declaration_Node (Current_Scope))) and then Nkind (N) = N_Attribute_Definition_Clause then declare Decl : Node_Id; begin Decl := First (Visible_Declarations (Specification (Unit_Declaration_Node (Current_Scope)))); while Present (Decl) loop if Nkind (Decl) = N_Private_Type_Declaration and then Ent = Full_View (Defining_Identifier (Decl)) and then Tagged_Present (Decl) and then No (Aspect_Specifications (Decl)) then Illegal_Indexing ("Indexing aspect cannot be specified on full view " & "if partial view is tagged"); return; end if; Next (Decl); end loop; end; end if; -- An indexing function must return either the default element of -- the container, or a reference type. For variable indexing it -- must be the latter. Default_Element := Find_Value_Of_Aspect (Etype (First_Formal (Subp)), Aspect_Iterator_Element); if Present (Default_Element) then Analyze (Default_Element); if Is_Entity_Name (Default_Element) and then not Covers (Entity (Default_Element), Ret_Type) and then False then Illegal_Indexing ("wrong return type for indexing function"); return; end if; end if; -- For variable_indexing the return type must be a reference type if Attr = Name_Variable_Indexing then if not Has_Implicit_Dereference (Ret_Type) then Illegal_Indexing ("variable indexing must return a reference type"); return; elsif Is_Access_Constant (Etype (First_Discriminant (Ret_Type))) then Illegal_Indexing ("variable indexing must return an access to variable"); return; end if; else if Has_Implicit_Dereference (Ret_Type) and then not Is_Access_Constant (Etype (First_Discriminant (Ret_Type))) then Illegal_Indexing ("constant indexing must return an access to constant"); return; elsif Is_Access_Type (Etype (First_Formal (Subp))) and then not Is_Access_Constant (Etype (First_Formal (Subp))) then Illegal_Indexing ("constant indexing must apply to an access to constant"); return; end if; end if; -- All checks succeeded. Indexing_Found := True; end Check_One_Function; ----------------------- -- Illegal_Indexing -- ----------------------- procedure Illegal_Indexing (Msg : String) is begin Error_Msg_NE (Msg, N, Ent); end Illegal_Indexing; -- Start of processing for Check_Indexing_Functions begin if In_Instance then Check_Inherited_Indexing; end if; Analyze (Expr); if not Is_Overloaded (Expr) then Check_One_Function (Entity (Expr)); else declare I : Interp_Index; It : Interp; begin Indexing_Found := False; Get_First_Interp (Expr, I, It); while Present (It.Nam) loop -- Note that analysis will have added the interpretation -- that corresponds to the dereference. We only check the -- subprogram itself. if Is_Overloadable (It.Nam) then Check_One_Function (It.Nam); end if; Get_Next_Interp (I, It); end loop; end; end if; if not Indexing_Found and then not Error_Posted (N) then Error_Msg_NE ("aspect Indexing requires a local function that " & "applies to type&", Expr, Ent); end if; end Check_Indexing_Functions; ------------------------------ -- Check_Iterator_Functions -- ------------------------------ procedure Check_Iterator_Functions is function Valid_Default_Iterator (Subp : Entity_Id) return Boolean; -- Check one possible interpretation for validity ---------------------------- -- Valid_Default_Iterator -- ---------------------------- function Valid_Default_Iterator (Subp : Entity_Id) return Boolean is Root_T : constant Entity_Id := Root_Type (Etype (Etype (Subp))); Formal : Entity_Id; begin if not Check_Primitive_Function (Subp) then return False; -- The return type must be derived from a type in an instance -- of Iterator.Interfaces, and thus its root type must have a -- predefined name. elsif Chars (Root_T) /= Name_Forward_Iterator and then Chars (Root_T) /= Name_Reversible_Iterator then return False; else Formal := First_Formal (Subp); end if; -- False if any subsequent formal has no default expression Formal := Next_Formal (Formal); while Present (Formal) loop if No (Expression (Parent (Formal))) then return False; end if; Next_Formal (Formal); end loop; -- True if all subsequent formals have default expressions return True; end Valid_Default_Iterator; -- Start of processing for Check_Iterator_Functions begin Analyze (Expr); if not Is_Entity_Name (Expr) then Error_Msg_N ("aspect Iterator must be a function name", Expr); end if; if not Is_Overloaded (Expr) then if not Check_Primitive_Function (Entity (Expr)) then Error_Msg_NE ("aspect Indexing requires a function that applies to type&", Entity (Expr), Ent); end if; -- Flag the default_iterator as well as the denoted function. if not Valid_Default_Iterator (Entity (Expr)) then Error_Msg_N ("improper function for default iterator!", Expr); end if; else declare Default : Entity_Id := Empty; I : Interp_Index; It : Interp; begin Get_First_Interp (Expr, I, It); while Present (It.Nam) loop if not Check_Primitive_Function (It.Nam) or else not Valid_Default_Iterator (It.Nam) then Remove_Interp (I); elsif Present (Default) then -- An explicit one should override an implicit one if Comes_From_Source (Default) = Comes_From_Source (It.Nam) then Error_Msg_N ("default iterator must be unique", Expr); Error_Msg_Sloc := Sloc (Default); Error_Msg_N ("\\possible interpretation#", Expr); Error_Msg_Sloc := Sloc (It.Nam); Error_Msg_N ("\\possible interpretation#", Expr); elsif Comes_From_Source (It.Nam) then Default := It.Nam; end if; else Default := It.Nam; end if; Get_Next_Interp (I, It); end loop; if Present (Default) then Set_Entity (Expr, Default); Set_Is_Overloaded (Expr, False); else Error_Msg_N ("no interpretation is a valid default iterator!", Expr); end if; end; end if; end Check_Iterator_Functions; ------------------------------- -- Check_Primitive_Function -- ------------------------------- function Check_Primitive_Function (Subp : Entity_Id) return Boolean is Ctrl : Entity_Id; begin if Ekind (Subp) /= E_Function then return False; end if; if No (First_Formal (Subp)) then return False; else Ctrl := Etype (First_Formal (Subp)); end if; -- To be a primitive operation subprogram has to be in same scope. if Scope (Ctrl) /= Scope (Subp) then return False; end if; -- Type of formal may be the class-wide type, an access to such, -- or an incomplete view. if Ctrl = Ent or else Ctrl = Class_Wide_Type (Ent) or else (Ekind (Ctrl) = E_Anonymous_Access_Type and then (Designated_Type (Ctrl) = Ent or else Designated_Type (Ctrl) = Class_Wide_Type (Ent))) or else (Ekind (Ctrl) = E_Incomplete_Type and then Full_View (Ctrl) = Ent) then null; else return False; end if; return True; end Check_Primitive_Function; ---------------------- -- Duplicate_Clause -- ---------------------- function Duplicate_Clause return Boolean is A : Node_Id; begin -- Nothing to do if this attribute definition clause comes from -- an aspect specification, since we could not be duplicating an -- explicit clause, and we dealt with the case of duplicated aspects -- in Analyze_Aspect_Specifications. if From_Aspect_Specification (N) then return False; end if; -- Otherwise current clause may duplicate previous clause, or a -- previously given pragma or aspect specification for the same -- aspect. A := Get_Rep_Item (U_Ent, Chars (N), Check_Parents => False); if Present (A) then Error_Msg_Name_1 := Chars (N); Error_Msg_Sloc := Sloc (A); Error_Msg_NE ("aspect% for & previously given#", N, U_Ent); return True; end if; return False; end Duplicate_Clause; -- Start of processing for Analyze_Attribute_Definition_Clause begin -- The following code is a defense against recursion. Not clear that -- this can happen legitimately, but perhaps some error situations can -- cause it, and we did see this recursion during testing. if Analyzed (N) then return; else Set_Analyzed (N, True); end if; Check_Restriction_No_Use_Of_Attribute (N); -- Ignore some selected attributes in CodePeer mode since they are not -- relevant in this context. if CodePeer_Mode then case Id is -- Ignore Component_Size in CodePeer mode, to avoid changing the -- internal representation of types by implicitly packing them. when Attribute_Component_Size => Rewrite (N, Make_Null_Statement (Sloc (N))); return; when others => null; end case; end if; -- Process Ignore_Rep_Clauses option if Ignore_Rep_Clauses then case Id is -- The following should be ignored. They do not affect legality -- and may be target dependent. The basic idea of -gnatI is to -- ignore any rep clauses that may be target dependent but do not -- affect legality (except possibly to be rejected because they -- are incompatible with the compilation target). when Attribute_Alignment | Attribute_Bit_Order | Attribute_Component_Size | Attribute_Machine_Radix | Attribute_Object_Size | Attribute_Size | Attribute_Small | Attribute_Stream_Size | Attribute_Value_Size => Kill_Rep_Clause (N); return; -- The following should not be ignored, because in the first place -- they are reasonably portable, and should not cause problems -- in compiling code from another target, and also they do affect -- legality, e.g. failing to provide a stream attribute for a type -- may make a program illegal. when Attribute_External_Tag | Attribute_Input | Attribute_Output | Attribute_Read | Attribute_Simple_Storage_Pool | Attribute_Storage_Pool | Attribute_Storage_Size | Attribute_Write => null; -- We do not do anything here with address clauses, they will be -- removed by Freeze later on, but for now, it works better to -- keep then in the tree. when Attribute_Address => null; -- Other cases are errors ("attribute& cannot be set with -- definition clause"), which will be caught below. when others => null; end case; end if; Analyze (Nam); Ent := Entity (Nam); if Rep_Item_Too_Early (Ent, N) then return; end if; -- Rep clause applies to full view of incomplete type or private type if -- we have one (if not, this is a premature use of the type). However, -- certain semantic checks need to be done on the specified entity (i.e. -- the private view), so we save it in Ent. if Is_Private_Type (Ent) and then Is_Derived_Type (Ent) and then not Is_Tagged_Type (Ent) and then No (Full_View (Ent)) then -- If this is a private type whose completion is a derivation from -- another private type, there is no full view, and the attribute -- belongs to the type itself, not its underlying parent. U_Ent := Ent; elsif Ekind (Ent) = E_Incomplete_Type then -- The attribute applies to the full view, set the entity of the -- attribute definition accordingly. Ent := Underlying_Type (Ent); U_Ent := Ent; Set_Entity (Nam, Ent); else U_Ent := Underlying_Type (Ent); end if; -- Avoid cascaded error if Etype (Nam) = Any_Type then return; -- Must be declared in current scope or in case of an aspect -- specification, must be visible in current scope. elsif Scope (Ent) /= Current_Scope and then not (From_Aspect_Specification (N) and then Scope_Within_Or_Same (Current_Scope, Scope (Ent))) then Error_Msg_N ("entity must be declared in this scope", Nam); return; -- Must not be a source renaming (we do have some cases where the -- expander generates a renaming, and those cases are OK, in such -- cases any attribute applies to the renamed object as well). elsif Is_Object (Ent) and then Present (Renamed_Object (Ent)) then -- Case of renamed object from source, this is an error if Comes_From_Source (Renamed_Object (Ent)) then Get_Name_String (Chars (N)); Error_Msg_Strlen := Name_Len; Error_Msg_String (1 .. Name_Len) := Name_Buffer (1 .. Name_Len); Error_Msg_N ("~ clause not allowed for a renaming declaration " & "(RM 13.1(6))", Nam); return; -- For the case of a compiler generated renaming, the attribute -- definition clause applies to the renamed object created by the -- expander. The easiest general way to handle this is to create a -- copy of the attribute definition clause for this object. elsif Is_Entity_Name (Renamed_Object (Ent)) then Insert_Action (N, Make_Attribute_Definition_Clause (Loc, Name => New_Occurrence_Of (Entity (Renamed_Object (Ent)), Loc), Chars => Chars (N), Expression => Duplicate_Subexpr (Expression (N)))); -- If the renamed object is not an entity, it must be a dereference -- of an unconstrained function call, and we must introduce a new -- declaration to capture the expression. This is needed in the case -- of 'Alignment, where the original declaration must be rewritten. else pragma Assert (Nkind (Renamed_Object (Ent)) = N_Explicit_Dereference); null; end if; -- If no underlying entity, use entity itself, applies to some -- previously detected error cases ??? elsif No (U_Ent) then U_Ent := Ent; -- Cannot specify for a subtype (exception Object/Value_Size) elsif Is_Type (U_Ent) and then not Is_First_Subtype (U_Ent) and then Id /= Attribute_Object_Size and then Id /= Attribute_Value_Size and then not From_At_Mod (N) then Error_Msg_N ("cannot specify attribute for subtype", Nam); return; end if; Set_Entity (N, U_Ent); -- Switch on particular attribute case Id is ------------- -- Address -- ------------- -- Address attribute definition clause when Attribute_Address => Address : begin -- A little error check, catch for X'Address use X'Address; if Nkind (Nam) = N_Identifier and then Nkind (Expr) = N_Attribute_Reference and then Attribute_Name (Expr) = Name_Address and then Nkind (Prefix (Expr)) = N_Identifier and then Chars (Nam) = Chars (Prefix (Expr)) then Error_Msg_NE ("address for & is self-referencing", Prefix (Expr), Ent); return; end if; -- Not that special case, carry on with analysis of expression Analyze_And_Resolve (Expr, RTE (RE_Address)); -- Even when ignoring rep clauses we need to indicate that the -- entity has an address clause and thus it is legal to declare -- it imported. Freeze will get rid of the address clause later. if Ignore_Rep_Clauses then if Ekind_In (U_Ent, E_Variable, E_Constant) then Record_Rep_Item (U_Ent, N); end if; return; end if; if Duplicate_Clause then null; -- Case of address clause for subprogram elsif Is_Subprogram (U_Ent) then if Has_Homonym (U_Ent) then Error_Msg_N ("address clause cannot be given for overloaded " & "subprogram", Nam); return; end if; -- For subprograms, all address clauses are permitted, and we -- mark the subprogram as having a deferred freeze so that Gigi -- will not elaborate it too soon. -- Above needs more comments, what is too soon about??? Set_Has_Delayed_Freeze (U_Ent); -- Case of address clause for entry elsif Ekind (U_Ent) = E_Entry then if Nkind (Parent (N)) = N_Task_Body then Error_Msg_N ("entry address must be specified in task spec", Nam); return; end if; -- For entries, we require a constant address Check_Constant_Address_Clause (Expr, U_Ent); -- Special checks for task types if Is_Task_Type (Scope (U_Ent)) and then Comes_From_Source (Scope (U_Ent)) then Error_Msg_N ("??entry address declared for entry in task type", N); Error_Msg_N ("\??only one task can be declared of this type", N); end if; -- Entry address clauses are obsolescent Check_Restriction (No_Obsolescent_Features, N); if Warn_On_Obsolescent_Feature then Error_Msg_N ("?j?attaching interrupt to task entry is an obsolescent " & "feature (RM J.7.1)", N); Error_Msg_N ("\?j?use interrupt procedure instead", N); end if; -- Case of an address clause for a controlled object which we -- consider to be erroneous. elsif Is_Controlled (Etype (U_Ent)) or else Has_Controlled_Component (Etype (U_Ent)) then Error_Msg_NE ("??controlled object& must not be overlaid", Nam, U_Ent); Error_Msg_N ("\??Program_Error will be raised at run time", Nam); Insert_Action (Declaration_Node (U_Ent), Make_Raise_Program_Error (Loc, Reason => PE_Overlaid_Controlled_Object)); return; -- Case of address clause for a (non-controlled) object elsif Ekind_In (U_Ent, E_Variable, E_Constant) then declare Expr : constant Node_Id := Expression (N); O_Ent : Entity_Id; Off : Boolean; begin -- Exported variables cannot have an address clause, because -- this cancels the effect of the pragma Export. if Is_Exported (U_Ent) then Error_Msg_N ("cannot export object with address clause", Nam); return; end if; Find_Overlaid_Entity (N, O_Ent, Off); if Present (O_Ent) then -- If the object overlays a constant object, mark it so if Is_Constant_Object (O_Ent) then Set_Overlays_Constant (U_Ent); end if; -- If the address clause is of the form: -- for X'Address use Y'Address; -- or -- C : constant Address := Y'Address; -- ... -- for X'Address use C; -- then we make an entry in the table to check the size -- and alignment of the overlaying variable. But we defer -- this check till after code generation to take full -- advantage of the annotation done by the back end. -- If the entity has a generic type, the check will be -- performed in the instance if the actual type justifies -- it, and we do not insert the clause in the table to -- prevent spurious warnings. -- Note: we used to test Comes_From_Source and only give -- this warning for source entities, but we have removed -- this test. It really seems bogus to generate overlays -- that would trigger this warning in generated code. -- Furthermore, by removing the test, we handle the -- aspect case properly. if Is_Object (O_Ent) and then not Is_Generic_Type (Etype (U_Ent)) and then Address_Clause_Overlay_Warnings then Address_Clause_Checks.Append ((N, U_Ent, No_Uint, O_Ent, Off)); end if; else -- If this is not an overlay, mark a variable as being -- volatile to prevent unwanted optimizations. It's a -- conservative interpretation of RM 13.3(19) for the -- cases where the compiler cannot detect potential -- aliasing issues easily and it also covers the case -- of an absolute address where the volatile aspect is -- kind of implicit. if Ekind (U_Ent) = E_Variable then Set_Treat_As_Volatile (U_Ent); end if; -- Make an entry in the table for an absolute address as -- above to check that the value is compatible with the -- alignment of the object. declare Addr : constant Node_Id := Address_Value (Expr); begin if Compile_Time_Known_Value (Addr) and then Address_Clause_Overlay_Warnings then Address_Clause_Checks.Append ((N, U_Ent, Expr_Value (Addr), Empty, False)); end if; end; end if; -- Overlaying controlled objects is erroneous. Emit warning -- but continue analysis because program is itself legal, -- and back end must see address clause. if Present (O_Ent) and then (Has_Controlled_Component (Etype (O_Ent)) or else Is_Controlled (Etype (O_Ent))) and then not Inside_A_Generic then Error_Msg_N ("??cannot use overlays with controlled objects", Expr); Error_Msg_N ("\??Program_Error will be raised at run time", Expr); Insert_Action (Declaration_Node (U_Ent), Make_Raise_Program_Error (Loc, Reason => PE_Overlaid_Controlled_Object)); -- Issue an unconditional warning for a constant overlaying -- a variable. For the reverse case, we will issue it only -- if the variable is modified. elsif Ekind (U_Ent) = E_Constant and then Present (O_Ent) and then not Overlays_Constant (U_Ent) and then Address_Clause_Overlay_Warnings then Error_Msg_N ("??constant overlays a variable", Expr); -- Imported variables can have an address clause, but then -- the import is pretty meaningless except to suppress -- initializations, so we do not need such variables to -- be statically allocated (and in fact it causes trouble -- if the address clause is a local value). elsif Is_Imported (U_Ent) then Set_Is_Statically_Allocated (U_Ent, False); end if; -- We mark a possible modification of a variable with an -- address clause, since it is likely aliasing is occurring. Note_Possible_Modification (Nam, Sure => False); -- Legality checks on the address clause for initialized -- objects is deferred until the freeze point, because -- a subsequent pragma might indicate that the object -- is imported and thus not initialized. Also, the address -- clause might involve entities that have yet to be -- elaborated. Set_Has_Delayed_Freeze (U_Ent); -- If an initialization call has been generated for this -- object, it needs to be deferred to after the freeze node -- we have just now added, otherwise GIGI will see a -- reference to the variable (as actual to the IP call) -- before its definition. declare Init_Call : constant Node_Id := Remove_Init_Call (U_Ent, N); begin if Present (Init_Call) then Append_Freeze_Action (U_Ent, Init_Call); -- Reset Initialization_Statements pointer so that -- if there is a pragma Import further down, it can -- clear any default initialization. Set_Initialization_Statements (U_Ent, Init_Call); end if; end; -- Entity has delayed freeze, so we will generate an -- alignment check at the freeze point unless suppressed. if not Range_Checks_Suppressed (U_Ent) and then not Alignment_Checks_Suppressed (U_Ent) then Set_Check_Address_Alignment (N); end if; -- Kill the size check code, since we are not allocating -- the variable, it is somewhere else. Kill_Size_Check_Code (U_Ent); end; -- Not a valid entity for an address clause else Error_Msg_N ("address cannot be given for &", Nam); end if; end Address; --------------- -- Alignment -- --------------- -- Alignment attribute definition clause when Attribute_Alignment => Alignment : declare Align : constant Uint := Get_Alignment_Value (Expr); Max_Align : constant Uint := UI_From_Int (Maximum_Alignment); begin FOnly := True; if not Is_Type (U_Ent) and then Ekind (U_Ent) /= E_Variable and then Ekind (U_Ent) /= E_Constant then Error_Msg_N ("alignment cannot be given for &", Nam); elsif Duplicate_Clause then null; elsif Align /= No_Uint then Set_Has_Alignment_Clause (U_Ent); -- Tagged type case, check for attempt to set alignment to a -- value greater than Max_Align, and reset if so. This error -- is suppressed in ASIS mode to allow for different ASIS -- back ends or ASIS-based tools to query the illegal clause. if Is_Tagged_Type (U_Ent) and then Align > Max_Align and then not ASIS_Mode then Error_Msg_N ("alignment for & set to Maximum_Aligment??", Nam); Set_Alignment (U_Ent, Max_Align); -- All other cases else Set_Alignment (U_Ent, Align); end if; -- For an array type, U_Ent is the first subtype. In that case, -- also set the alignment of the anonymous base type so that -- other subtypes (such as the itypes for aggregates of the -- type) also receive the expected alignment. if Is_Array_Type (U_Ent) then Set_Alignment (Base_Type (U_Ent), Align); end if; end if; end Alignment; --------------- -- Bit_Order -- --------------- -- Bit_Order attribute definition clause when Attribute_Bit_Order => Bit_Order : declare begin if not Is_Record_Type (U_Ent) then Error_Msg_N ("Bit_Order can only be defined for record type", Nam); elsif Duplicate_Clause then null; else Analyze_And_Resolve (Expr, RTE (RE_Bit_Order)); if Etype (Expr) = Any_Type then return; elsif not Is_OK_Static_Expression (Expr) then Flag_Non_Static_Expr ("Bit_Order requires static expression!", Expr); else if (Expr_Value (Expr) = 0) /= Bytes_Big_Endian then Set_Reverse_Bit_Order (Base_Type (U_Ent), True); end if; end if; end if; end Bit_Order; -------------------- -- Component_Size -- -------------------- -- Component_Size attribute definition clause when Attribute_Component_Size => Component_Size_Case : declare Csize : constant Uint := Static_Integer (Expr); Ctyp : Entity_Id; Btype : Entity_Id; Biased : Boolean; New_Ctyp : Entity_Id; Decl : Node_Id; begin if not Is_Array_Type (U_Ent) then Error_Msg_N ("component size requires array type", Nam); return; end if; Btype := Base_Type (U_Ent); Ctyp := Component_Type (Btype); if Duplicate_Clause then null; elsif Rep_Item_Too_Early (Btype, N) then null; elsif Csize /= No_Uint then Check_Size (Expr, Ctyp, Csize, Biased); -- For the biased case, build a declaration for a subtype that -- will be used to represent the biased subtype that reflects -- the biased representation of components. We need the subtype -- to get proper conversions on referencing elements of the -- array. if Biased then New_Ctyp := Make_Defining_Identifier (Loc, Chars => New_External_Name (Chars (U_Ent), 'C', 0, 'T')); Decl := Make_Subtype_Declaration (Loc, Defining_Identifier => New_Ctyp, Subtype_Indication => New_Occurrence_Of (Component_Type (Btype), Loc)); Set_Parent (Decl, N); Analyze (Decl, Suppress => All_Checks); Set_Has_Delayed_Freeze (New_Ctyp, False); Set_Esize (New_Ctyp, Csize); Set_RM_Size (New_Ctyp, Csize); Init_Alignment (New_Ctyp); Set_Is_Itype (New_Ctyp, True); Set_Associated_Node_For_Itype (New_Ctyp, U_Ent); Set_Component_Type (Btype, New_Ctyp); Set_Biased (New_Ctyp, N, "component size clause"); end if; Set_Component_Size (Btype, Csize); -- Deal with warning on overridden size if Warn_On_Overridden_Size and then Has_Size_Clause (Ctyp) and then RM_Size (Ctyp) /= Csize then Error_Msg_NE ("component size overrides size clause for&?S?", N, Ctyp); end if; Set_Has_Component_Size_Clause (Btype, True); Set_Has_Non_Standard_Rep (Btype, True); end if; end Component_Size_Case; ----------------------- -- Constant_Indexing -- ----------------------- when Attribute_Constant_Indexing => Check_Indexing_Functions; --------- -- CPU -- --------- when Attribute_CPU => CPU : begin -- CPU attribute definition clause not allowed except from aspect -- specification. if From_Aspect_Specification (N) then if not Is_Task_Type (U_Ent) then Error_Msg_N ("CPU can only be defined for task", Nam); elsif Duplicate_Clause then null; else -- The expression must be analyzed in the special manner -- described in "Handling of Default and Per-Object -- Expressions" in sem.ads. -- The visibility to the discriminants must be restored Push_Scope_And_Install_Discriminants (U_Ent); Preanalyze_Spec_Expression (Expr, RTE (RE_CPU_Range)); Uninstall_Discriminants_And_Pop_Scope (U_Ent); if not Is_OK_Static_Expression (Expr) then Check_Restriction (Static_Priorities, Expr); end if; end if; else Error_Msg_N ("attribute& cannot be set with definition clause", N); end if; end CPU; ---------------------- -- Default_Iterator -- ---------------------- when Attribute_Default_Iterator => Default_Iterator : declare Func : Entity_Id; Typ : Entity_Id; begin -- If target type is untagged, further checks are irrelevant if not Is_Tagged_Type (U_Ent) then Error_Msg_N ("aspect Default_Iterator applies to tagged type", Nam); return; end if; Check_Iterator_Functions; Analyze (Expr); if not Is_Entity_Name (Expr) or else Ekind (Entity (Expr)) /= E_Function then Error_Msg_N ("aspect Iterator must be a function", Expr); return; else Func := Entity (Expr); end if; -- The type of the first parameter must be T, T'class, or a -- corresponding access type (5.5.1 (8/3). If function is -- parameterless label type accordingly. if No (First_Formal (Func)) then Typ := Any_Type; else Typ := Etype (First_Formal (Func)); end if; if Typ = U_Ent or else Typ = Class_Wide_Type (U_Ent) or else (Is_Access_Type (Typ) and then Designated_Type (Typ) = U_Ent) or else (Is_Access_Type (Typ) and then Designated_Type (Typ) = Class_Wide_Type (U_Ent)) then null; else Error_Msg_NE ("Default Iterator must be a primitive of&", Func, U_Ent); end if; end Default_Iterator; ------------------------ -- Dispatching_Domain -- ------------------------ when Attribute_Dispatching_Domain => Dispatching_Domain : begin -- Dispatching_Domain attribute definition clause not allowed -- except from aspect specification. if From_Aspect_Specification (N) then if not Is_Task_Type (U_Ent) then Error_Msg_N ("Dispatching_Domain can only be defined for task", Nam); elsif Duplicate_Clause then null; else -- The expression must be analyzed in the special manner -- described in "Handling of Default and Per-Object -- Expressions" in sem.ads. -- The visibility to the discriminants must be restored Push_Scope_And_Install_Discriminants (U_Ent); Preanalyze_Spec_Expression (Expr, RTE (RE_Dispatching_Domain)); Uninstall_Discriminants_And_Pop_Scope (U_Ent); end if; else Error_Msg_N ("attribute& cannot be set with definition clause", N); end if; end Dispatching_Domain; ------------------ -- External_Tag -- ------------------ when Attribute_External_Tag => External_Tag : begin if not Is_Tagged_Type (U_Ent) then Error_Msg_N ("should be a tagged type", Nam); end if; if Duplicate_Clause then null; else Analyze_And_Resolve (Expr, Standard_String); if not Is_OK_Static_Expression (Expr) then Flag_Non_Static_Expr ("static string required for tag name!", Nam); end if; if not Is_Library_Level_Entity (U_Ent) then Error_Msg_NE ("??non-unique external tag supplied for &", N, U_Ent); Error_Msg_N ("\??same external tag applies to all subprogram calls", N); Error_Msg_N ("\??corresponding internal tag cannot be obtained", N); end if; end if; end External_Tag; -------------------------- -- Implicit_Dereference -- -------------------------- when Attribute_Implicit_Dereference => -- Legality checks already performed at the point of the type -- declaration, aspect is not delayed. null; ----------- -- Input -- ----------- when Attribute_Input => Analyze_Stream_TSS_Definition (TSS_Stream_Input); Set_Has_Specified_Stream_Input (Ent); ------------------------ -- Interrupt_Priority -- ------------------------ when Attribute_Interrupt_Priority => Interrupt_Priority : begin -- Interrupt_Priority attribute definition clause not allowed -- except from aspect specification. if From_Aspect_Specification (N) then if not Is_Concurrent_Type (U_Ent) then Error_Msg_N ("Interrupt_Priority can only be defined for task and " & "protected object", Nam); elsif Duplicate_Clause then null; else -- The expression must be analyzed in the special manner -- described in "Handling of Default and Per-Object -- Expressions" in sem.ads. -- The visibility to the discriminants must be restored Push_Scope_And_Install_Discriminants (U_Ent); Preanalyze_Spec_Expression (Expr, RTE (RE_Interrupt_Priority)); Uninstall_Discriminants_And_Pop_Scope (U_Ent); -- Check the No_Task_At_Interrupt_Priority restriction if Is_Task_Type (U_Ent) then Check_Restriction (No_Task_At_Interrupt_Priority, N); end if; end if; else Error_Msg_N ("attribute& cannot be set with definition clause", N); end if; end Interrupt_Priority; -------------- -- Iterable -- -------------- when Attribute_Iterable => Analyze (Expr); if Nkind (Expr) /= N_Aggregate then Error_Msg_N ("aspect Iterable must be an aggregate", Expr); end if; declare Assoc : Node_Id; begin Assoc := First (Component_Associations (Expr)); while Present (Assoc) loop if not Is_Entity_Name (Expression (Assoc)) then Error_Msg_N ("value must be a function", Assoc); end if; Next (Assoc); end loop; end; ---------------------- -- Iterator_Element -- ---------------------- when Attribute_Iterator_Element => Analyze (Expr); if not Is_Entity_Name (Expr) or else not Is_Type (Entity (Expr)) then Error_Msg_N ("aspect Iterator_Element must be a type", Expr); end if; ------------------- -- Machine_Radix -- ------------------- -- Machine radix attribute definition clause when Attribute_Machine_Radix => Machine_Radix : declare Radix : constant Uint := Static_Integer (Expr); begin if not Is_Decimal_Fixed_Point_Type (U_Ent) then Error_Msg_N ("decimal fixed-point type expected for &", Nam); elsif Duplicate_Clause then null; elsif Radix /= No_Uint then Set_Has_Machine_Radix_Clause (U_Ent); Set_Has_Non_Standard_Rep (Base_Type (U_Ent)); if Radix = 2 then null; elsif Radix = 10 then Set_Machine_Radix_10 (U_Ent); -- The following error is suppressed in ASIS mode to allow for -- different ASIS back ends or ASIS-based tools to query the -- illegal clause. elsif not ASIS_Mode then Error_Msg_N ("machine radix value must be 2 or 10", Expr); end if; end if; end Machine_Radix; ----------------- -- Object_Size -- ----------------- -- Object_Size attribute definition clause when Attribute_Object_Size => Object_Size : declare Size : constant Uint := Static_Integer (Expr); Biased : Boolean; pragma Warnings (Off, Biased); begin if not Is_Type (U_Ent) then Error_Msg_N ("Object_Size cannot be given for &", Nam); elsif Duplicate_Clause then null; else Check_Size (Expr, U_Ent, Size, Biased); -- The following errors are suppressed in ASIS mode to allow -- for different ASIS back ends or ASIS-based tools to query -- the illegal clause. if ASIS_Mode then null; elsif Is_Scalar_Type (U_Ent) then if Size /= 8 and then Size /= 16 and then Size /= 32 and then UI_Mod (Size, 64) /= 0 then Error_Msg_N ("Object_Size must be 8, 16, 32, or multiple of 64", Expr); end if; elsif Size mod 8 /= 0 then Error_Msg_N ("Object_Size must be a multiple of 8", Expr); end if; Set_Esize (U_Ent, Size); Set_Has_Object_Size_Clause (U_Ent); Alignment_Check_For_Size_Change (U_Ent, Size); end if; end Object_Size; ------------ -- Output -- ------------ when Attribute_Output => Analyze_Stream_TSS_Definition (TSS_Stream_Output); Set_Has_Specified_Stream_Output (Ent); -------------- -- Priority -- -------------- when Attribute_Priority => Priority : begin -- Priority attribute definition clause not allowed except from -- aspect specification. if From_Aspect_Specification (N) then if not (Is_Concurrent_Type (U_Ent) or else Ekind (U_Ent) = E_Procedure) then Error_Msg_N ("Priority can only be defined for task and protected " & "object", Nam); elsif Duplicate_Clause then null; else -- The expression must be analyzed in the special manner -- described in "Handling of Default and Per-Object -- Expressions" in sem.ads. -- The visibility to the discriminants must be restored Push_Scope_And_Install_Discriminants (U_Ent); Preanalyze_Spec_Expression (Expr, Standard_Integer); Uninstall_Discriminants_And_Pop_Scope (U_Ent); if not Is_OK_Static_Expression (Expr) then Check_Restriction (Static_Priorities, Expr); end if; end if; else Error_Msg_N ("attribute& cannot be set with definition clause", N); end if; end Priority; ---------- -- Read -- ---------- when Attribute_Read => Analyze_Stream_TSS_Definition (TSS_Stream_Read); Set_Has_Specified_Stream_Read (Ent); -------------------------- -- Scalar_Storage_Order -- -------------------------- -- Scalar_Storage_Order attribute definition clause when Attribute_Scalar_Storage_Order => Scalar_Storage_Order : declare begin if not (Is_Record_Type (U_Ent) or else Is_Array_Type (U_Ent)) then Error_Msg_N ("Scalar_Storage_Order can only be defined for record or " & "array type", Nam); elsif Duplicate_Clause then null; else Analyze_And_Resolve (Expr, RTE (RE_Bit_Order)); if Etype (Expr) = Any_Type then return; elsif not Is_OK_Static_Expression (Expr) then Flag_Non_Static_Expr ("Scalar_Storage_Order requires static expression!", Expr); elsif (Expr_Value (Expr) = 0) /= Bytes_Big_Endian then -- Here for the case of a non-default (i.e. non-confirming) -- Scalar_Storage_Order attribute definition. if Support_Nondefault_SSO_On_Target then Set_Reverse_Storage_Order (Base_Type (U_Ent), True); else Error_Msg_N ("non-default Scalar_Storage_Order not supported on " & "target", Expr); end if; end if; -- Clear SSO default indications since explicit setting of the -- order overrides the defaults. Set_SSO_Set_Low_By_Default (Base_Type (U_Ent), False); Set_SSO_Set_High_By_Default (Base_Type (U_Ent), False); end if; end Scalar_Storage_Order; ---------- -- Size -- ---------- -- Size attribute definition clause when Attribute_Size => Size : declare Size : constant Uint := Static_Integer (Expr); Etyp : Entity_Id; Biased : Boolean; begin FOnly := True; if Duplicate_Clause then null; elsif not Is_Type (U_Ent) and then Ekind (U_Ent) /= E_Variable and then Ekind (U_Ent) /= E_Constant then Error_Msg_N ("size cannot be given for &", Nam); elsif Is_Array_Type (U_Ent) and then not Is_Constrained (U_Ent) then Error_Msg_N ("size cannot be given for unconstrained array", Nam); elsif Size /= No_Uint then if Is_Type (U_Ent) then Etyp := U_Ent; else Etyp := Etype (U_Ent); end if; -- Check size, note that Gigi is in charge of checking that the -- size of an array or record type is OK. Also we do not check -- the size in the ordinary fixed-point case, since it is too -- early to do so (there may be subsequent small clause that -- affects the size). We can check the size if a small clause -- has already been given. if not Is_Ordinary_Fixed_Point_Type (U_Ent) or else Has_Small_Clause (U_Ent) then Check_Size (Expr, Etyp, Size, Biased); Set_Biased (U_Ent, N, "size clause", Biased); end if; -- For types set RM_Size and Esize if possible if Is_Type (U_Ent) then Set_RM_Size (U_Ent, Size); -- For elementary types, increase Object_Size to power of 2, -- but not less than a storage unit in any case (normally -- this means it will be byte addressable). -- For all other types, nothing else to do, we leave Esize -- (object size) unset, the back end will set it from the -- size and alignment in an appropriate manner. -- In both cases, we check whether the alignment must be -- reset in the wake of the size change. if Is_Elementary_Type (U_Ent) then if Size <= System_Storage_Unit then Init_Esize (U_Ent, System_Storage_Unit); elsif Size <= 16 then Init_Esize (U_Ent, 16); elsif Size <= 32 then Init_Esize (U_Ent, 32); else Set_Esize (U_Ent, (Size + 63) / 64 * 64); end if; Alignment_Check_For_Size_Change (U_Ent, Esize (U_Ent)); else Alignment_Check_For_Size_Change (U_Ent, Size); end if; -- For objects, set Esize only else -- The following error is suppressed in ASIS mode to allow -- for different ASIS back ends or ASIS-based tools to query -- the illegal clause. if Is_Elementary_Type (Etyp) and then Size /= System_Storage_Unit and then Size /= System_Storage_Unit * 2 and then Size /= System_Storage_Unit * 4 and then Size /= System_Storage_Unit * 8 and then not ASIS_Mode then Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit); Error_Msg_Uint_2 := Error_Msg_Uint_1 * 8; Error_Msg_N ("size for primitive object must be a power of 2 in " & "the range ^-^", N); end if; Set_Esize (U_Ent, Size); end if; Set_Has_Size_Clause (U_Ent); end if; end Size; ----------- -- Small -- ----------- -- Small attribute definition clause when Attribute_Small => Small : declare Implicit_Base : constant Entity_Id := Base_Type (U_Ent); Small : Ureal; begin Analyze_And_Resolve (Expr, Any_Real); if Etype (Expr) = Any_Type then return; elsif not Is_OK_Static_Expression (Expr) then Flag_Non_Static_Expr ("small requires static expression!", Expr); return; else Small := Expr_Value_R (Expr); if Small <= Ureal_0 then Error_Msg_N ("small value must be greater than zero", Expr); return; end if; end if; if not Is_Ordinary_Fixed_Point_Type (U_Ent) then Error_Msg_N ("small requires an ordinary fixed point type", Nam); elsif Has_Small_Clause (U_Ent) then Error_Msg_N ("small already given for &", Nam); elsif Small > Delta_Value (U_Ent) then Error_Msg_N ("small value must not be greater than delta value", Nam); else Set_Small_Value (U_Ent, Small); Set_Small_Value (Implicit_Base, Small); Set_Has_Small_Clause (U_Ent); Set_Has_Small_Clause (Implicit_Base); Set_Has_Non_Standard_Rep (Implicit_Base); end if; end Small; ------------------ -- Storage_Pool -- ------------------ -- Storage_Pool attribute definition clause when Attribute_Storage_Pool | Attribute_Simple_Storage_Pool => declare Pool : Entity_Id; T : Entity_Id; begin if Ekind (U_Ent) = E_Access_Subprogram_Type then Error_Msg_N ("storage pool cannot be given for access-to-subprogram type", Nam); return; elsif not Ekind_In (U_Ent, E_Access_Type, E_General_Access_Type) then Error_Msg_N ("storage pool can only be given for access types", Nam); return; elsif Is_Derived_Type (U_Ent) then Error_Msg_N ("storage pool cannot be given for a derived access type", Nam); elsif Duplicate_Clause then return; elsif Present (Associated_Storage_Pool (U_Ent)) then Error_Msg_N ("storage pool already given for &", Nam); return; end if; -- Check for Storage_Size previously given declare SS : constant Node_Id := Get_Attribute_Definition_Clause (U_Ent, Attribute_Storage_Size); begin if Present (SS) then Check_Pool_Size_Clash (U_Ent, N, SS); end if; end; -- Storage_Pool case if Id = Attribute_Storage_Pool then Analyze_And_Resolve (Expr, Class_Wide_Type (RTE (RE_Root_Storage_Pool))); -- In the Simple_Storage_Pool case, we allow a variable of any -- simple storage pool type, so we Resolve without imposing an -- expected type. else Analyze_And_Resolve (Expr); if not Present (Get_Rep_Pragma (Etype (Expr), Name_Simple_Storage_Pool_Type)) then Error_Msg_N ("expression must be of a simple storage pool type", Expr); end if; end if; if not Denotes_Variable (Expr) then Error_Msg_N ("storage pool must be a variable", Expr); return; end if; if Nkind (Expr) = N_Type_Conversion then T := Etype (Expression (Expr)); else T := Etype (Expr); end if; -- The Stack_Bounded_Pool is used internally for implementing -- access types with a Storage_Size. Since it only work properly -- when used on one specific type, we need to check that it is not -- hijacked improperly: -- type T is access Integer; -- for T'Storage_Size use n; -- type Q is access Float; -- for Q'Storage_Size use T'Storage_Size; -- incorrect if RTE_Available (RE_Stack_Bounded_Pool) and then Base_Type (T) = RTE (RE_Stack_Bounded_Pool) then Error_Msg_N ("non-shareable internal Pool", Expr); return; end if; -- If the argument is a name that is not an entity name, then -- we construct a renaming operation to define an entity of -- type storage pool. if not Is_Entity_Name (Expr) and then Is_Object_Reference (Expr) then Pool := Make_Temporary (Loc, 'P', Expr); declare Rnode : constant Node_Id := Make_Object_Renaming_Declaration (Loc, Defining_Identifier => Pool, Subtype_Mark => New_Occurrence_Of (Etype (Expr), Loc), Name => Expr); begin -- If the attribute definition clause comes from an aspect -- clause, then insert the renaming before the associated -- entity's declaration, since the attribute clause has -- not yet been appended to the declaration list. if From_Aspect_Specification (N) then Insert_Before (Parent (Entity (N)), Rnode); else Insert_Before (N, Rnode); end if; Analyze (Rnode); Set_Associated_Storage_Pool (U_Ent, Pool); end; elsif Is_Entity_Name (Expr) then Pool := Entity (Expr); -- If pool is a renamed object, get original one. This can -- happen with an explicit renaming, and within instances. while Present (Renamed_Object (Pool)) and then Is_Entity_Name (Renamed_Object (Pool)) loop Pool := Entity (Renamed_Object (Pool)); end loop; if Present (Renamed_Object (Pool)) and then Nkind (Renamed_Object (Pool)) = N_Type_Conversion and then Is_Entity_Name (Expression (Renamed_Object (Pool))) then Pool := Entity (Expression (Renamed_Object (Pool))); end if; Set_Associated_Storage_Pool (U_Ent, Pool); elsif Nkind (Expr) = N_Type_Conversion and then Is_Entity_Name (Expression (Expr)) and then Nkind (Original_Node (Expr)) = N_Attribute_Reference then Pool := Entity (Expression (Expr)); Set_Associated_Storage_Pool (U_Ent, Pool); else Error_Msg_N ("incorrect reference to a Storage Pool", Expr); return; end if; end; ------------------ -- Storage_Size -- ------------------ -- Storage_Size attribute definition clause when Attribute_Storage_Size => Storage_Size : declare Btype : constant Entity_Id := Base_Type (U_Ent); begin if Is_Task_Type (U_Ent) then -- Check obsolescent (but never obsolescent if from aspect) if not From_Aspect_Specification (N) then Check_Restriction (No_Obsolescent_Features, N); if Warn_On_Obsolescent_Feature then Error_Msg_N ("?j?storage size clause for task is an obsolescent " & "feature (RM J.9)", N); Error_Msg_N ("\?j?use Storage_Size pragma instead", N); end if; end if; FOnly := True; end if; if not Is_Access_Type (U_Ent) and then Ekind (U_Ent) /= E_Task_Type then Error_Msg_N ("storage size cannot be given for &", Nam); elsif Is_Access_Type (U_Ent) and Is_Derived_Type (U_Ent) then Error_Msg_N ("storage size cannot be given for a derived access type", Nam); elsif Duplicate_Clause then null; else Analyze_And_Resolve (Expr, Any_Integer); if Is_Access_Type (U_Ent) then -- Check for Storage_Pool previously given declare SP : constant Node_Id := Get_Attribute_Definition_Clause (U_Ent, Attribute_Storage_Pool); begin if Present (SP) then Check_Pool_Size_Clash (U_Ent, SP, N); end if; end; -- Special case of for x'Storage_Size use 0 if Is_OK_Static_Expression (Expr) and then Expr_Value (Expr) = 0 then Set_No_Pool_Assigned (Btype); end if; end if; Set_Has_Storage_Size_Clause (Btype); end if; end Storage_Size; ----------------- -- Stream_Size -- ----------------- when Attribute_Stream_Size => Stream_Size : declare Size : constant Uint := Static_Integer (Expr); begin if Ada_Version <= Ada_95 then Check_Restriction (No_Implementation_Attributes, N); end if; if Duplicate_Clause then null; elsif Is_Elementary_Type (U_Ent) then -- The following errors are suppressed in ASIS mode to allow -- for different ASIS back ends or ASIS-based tools to query -- the illegal clause. if ASIS_Mode then null; elsif Size /= System_Storage_Unit and then Size /= System_Storage_Unit * 2 and then Size /= System_Storage_Unit * 4 and then Size /= System_Storage_Unit * 8 then Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit); Error_Msg_N ("stream size for elementary type must be a power of 2 " & "and at least ^", N); elsif RM_Size (U_Ent) > Size then Error_Msg_Uint_1 := RM_Size (U_Ent); Error_Msg_N ("stream size for elementary type must be a power of 2 " & "and at least ^", N); end if; Set_Has_Stream_Size_Clause (U_Ent); else Error_Msg_N ("Stream_Size cannot be given for &", Nam); end if; end Stream_Size; ---------------- -- Value_Size -- ---------------- -- Value_Size attribute definition clause when Attribute_Value_Size => Value_Size : declare Size : constant Uint := Static_Integer (Expr); Biased : Boolean; begin if not Is_Type (U_Ent) then Error_Msg_N ("Value_Size cannot be given for &", Nam); elsif Duplicate_Clause then null; elsif Is_Array_Type (U_Ent) and then not Is_Constrained (U_Ent) then Error_Msg_N ("Value_Size cannot be given for unconstrained array", Nam); else if Is_Elementary_Type (U_Ent) then Check_Size (Expr, U_Ent, Size, Biased); Set_Biased (U_Ent, N, "value size clause", Biased); end if; Set_RM_Size (U_Ent, Size); end if; end Value_Size; ----------------------- -- Variable_Indexing -- ----------------------- when Attribute_Variable_Indexing => Check_Indexing_Functions; ----------- -- Write -- ----------- when Attribute_Write => Analyze_Stream_TSS_Definition (TSS_Stream_Write); Set_Has_Specified_Stream_Write (Ent); -- All other attributes cannot be set when others => Error_Msg_N ("attribute& cannot be set with definition clause", N); end case; -- The test for the type being frozen must be performed after any -- expression the clause has been analyzed since the expression itself -- might cause freezing that makes the clause illegal. if Rep_Item_Too_Late (U_Ent, N, FOnly) then return; end if; end Analyze_Attribute_Definition_Clause; ---------------------------- -- Analyze_Code_Statement -- ---------------------------- procedure Analyze_Code_Statement (N : Node_Id) is HSS : constant Node_Id := Parent (N); SBody : constant Node_Id := Parent (HSS); Subp : constant Entity_Id := Current_Scope; Stmt : Node_Id; Decl : Node_Id; StmtO : Node_Id; DeclO : Node_Id; begin -- Accept foreign code statements for CodePeer. The analysis is skipped -- to avoid rejecting unrecognized constructs. if CodePeer_Mode then Set_Analyzed (N); return; end if; -- Analyze and check we get right type, note that this implements the -- requirement (RM 13.8(1)) that Machine_Code be with'ed, since that is -- the only way that Asm_Insn could possibly be visible. Analyze_And_Resolve (Expression (N)); if Etype (Expression (N)) = Any_Type then return; elsif Etype (Expression (N)) /= RTE (RE_Asm_Insn) then Error_Msg_N ("incorrect type for code statement", N); return; end if; Check_Code_Statement (N); -- Make sure we appear in the handled statement sequence of a subprogram -- (RM 13.8(3)). if Nkind (HSS) /= N_Handled_Sequence_Of_Statements or else Nkind (SBody) /= N_Subprogram_Body then Error_Msg_N ("code statement can only appear in body of subprogram", N); return; end if; -- Do remaining checks (RM 13.8(3)) if not already done if not Is_Machine_Code_Subprogram (Subp) then Set_Is_Machine_Code_Subprogram (Subp); -- No exception handlers allowed if Present (Exception_Handlers (HSS)) then Error_Msg_N ("exception handlers not permitted in machine code subprogram", First (Exception_Handlers (HSS))); end if; -- No declarations other than use clauses and pragmas (we allow -- certain internally generated declarations as well). Decl := First (Declarations (SBody)); while Present (Decl) loop DeclO := Original_Node (Decl); if Comes_From_Source (DeclO) and not Nkind_In (DeclO, N_Pragma, N_Use_Package_Clause, N_Use_Type_Clause, N_Implicit_Label_Declaration) then Error_Msg_N ("this declaration not allowed in machine code subprogram", DeclO); end if; Next (Decl); end loop; -- No statements other than code statements, pragmas, and labels. -- Again we allow certain internally generated statements. -- In Ada 2012, qualified expressions are names, and the code -- statement is initially parsed as a procedure call. Stmt := First (Statements (HSS)); while Present (Stmt) loop StmtO := Original_Node (Stmt); -- A procedure call transformed into a code statement is OK if Ada_Version >= Ada_2012 and then Nkind (StmtO) = N_Procedure_Call_Statement and then Nkind (Name (StmtO)) = N_Qualified_Expression then null; elsif Comes_From_Source (StmtO) and then not Nkind_In (StmtO, N_Pragma, N_Label, N_Code_Statement) then Error_Msg_N ("this statement is not allowed in machine code subprogram", StmtO); end if; Next (Stmt); end loop; end if; end Analyze_Code_Statement; ----------------------------------------------- -- Analyze_Enumeration_Representation_Clause -- ----------------------------------------------- procedure Analyze_Enumeration_Representation_Clause (N : Node_Id) is Ident : constant Node_Id := Identifier (N); Aggr : constant Node_Id := Array_Aggregate (N); Enumtype : Entity_Id; Elit : Entity_Id; Expr : Node_Id; Assoc : Node_Id; Choice : Node_Id; Val : Uint; Err : Boolean := False; -- Set True to avoid cascade errors and crashes on incorrect source code Lo : constant Uint := Expr_Value (Type_Low_Bound (Universal_Integer)); Hi : constant Uint := Expr_Value (Type_High_Bound (Universal_Integer)); -- Allowed range of universal integer (= allowed range of enum lit vals) Min : Uint; Max : Uint; -- Minimum and maximum values of entries Max_Node : Node_Id; -- Pointer to node for literal providing max value begin if Ignore_Rep_Clauses then Kill_Rep_Clause (N); return; end if; -- Ignore enumeration rep clauses by default in CodePeer mode, -- unless -gnatd.I is specified, as a work around for potential false -- positive messages. if CodePeer_Mode and not Debug_Flag_Dot_II then return; end if; -- First some basic error checks Find_Type (Ident); Enumtype := Entity (Ident); if Enumtype = Any_Type or else Rep_Item_Too_Early (Enumtype, N) then return; else Enumtype := Underlying_Type (Enumtype); end if; if not Is_Enumeration_Type (Enumtype) then Error_Msg_NE ("enumeration type required, found}", Ident, First_Subtype (Enumtype)); return; end if; -- Ignore rep clause on generic actual type. This will already have -- been flagged on the template as an error, and this is the safest -- way to ensure we don't get a junk cascaded message in the instance. if Is_Generic_Actual_Type (Enumtype) then return; -- Type must be in current scope elsif Scope (Enumtype) /= Current_Scope then Error_Msg_N ("type must be declared in this scope", Ident); return; -- Type must be a first subtype elsif not Is_First_Subtype (Enumtype) then Error_Msg_N ("cannot give enumeration rep clause for subtype", N); return; -- Ignore duplicate rep clause elsif Has_Enumeration_Rep_Clause (Enumtype) then Error_Msg_N ("duplicate enumeration rep clause ignored", N); return; -- Don't allow rep clause for standard [wide_[wide_]]character elsif Is_Standard_Character_Type (Enumtype) then Error_Msg_N ("enumeration rep clause not allowed for this type", N); return; -- Check that the expression is a proper aggregate (no parentheses) elsif Paren_Count (Aggr) /= 0 then Error_Msg ("extra parentheses surrounding aggregate not allowed", First_Sloc (Aggr)); return; -- All tests passed, so set rep clause in place else Set_Has_Enumeration_Rep_Clause (Enumtype); Set_Has_Enumeration_Rep_Clause (Base_Type (Enumtype)); end if; -- Now we process the aggregate. Note that we don't use the normal -- aggregate code for this purpose, because we don't want any of the -- normal expansion activities, and a number of special semantic -- rules apply (including the component type being any integer type) Elit := First_Literal (Enumtype); -- First the positional entries if any if Present (Expressions (Aggr)) then Expr := First (Expressions (Aggr)); while Present (Expr) loop if No (Elit) then Error_Msg_N ("too many entries in aggregate", Expr); return; end if; Val := Static_Integer (Expr); -- Err signals that we found some incorrect entries processing -- the list. The final checks for completeness and ordering are -- skipped in this case. if Val = No_Uint then Err := True; elsif Val < Lo or else Hi < Val then Error_Msg_N ("value outside permitted range", Expr); Err := True; end if; Set_Enumeration_Rep (Elit, Val); Set_Enumeration_Rep_Expr (Elit, Expr); Next (Expr); Next (Elit); end loop; end if; -- Now process the named entries if present if Present (Component_Associations (Aggr)) then Assoc := First (Component_Associations (Aggr)); while Present (Assoc) loop Choice := First (Choices (Assoc)); if Present (Next (Choice)) then Error_Msg_N ("multiple choice not allowed here", Next (Choice)); Err := True; end if; if Nkind (Choice) = N_Others_Choice then Error_Msg_N ("others choice not allowed here", Choice); Err := True; elsif Nkind (Choice) = N_Range then -- ??? should allow zero/one element range here Error_Msg_N ("range not allowed here", Choice); Err := True; else Analyze_And_Resolve (Choice, Enumtype); if Error_Posted (Choice) then Err := True; end if; if not Err then if Is_Entity_Name (Choice) and then Is_Type (Entity (Choice)) then Error_Msg_N ("subtype name not allowed here", Choice); Err := True; -- ??? should allow static subtype with zero/one entry elsif Etype (Choice) = Base_Type (Enumtype) then if not Is_OK_Static_Expression (Choice) then Flag_Non_Static_Expr ("non-static expression used for choice!", Choice); Err := True; else Elit := Expr_Value_E (Choice); if Present (Enumeration_Rep_Expr (Elit)) then Error_Msg_Sloc := Sloc (Enumeration_Rep_Expr (Elit)); Error_Msg_NE ("representation for& previously given#", Choice, Elit); Err := True; end if; Set_Enumeration_Rep_Expr (Elit, Expression (Assoc)); Expr := Expression (Assoc); Val := Static_Integer (Expr); if Val = No_Uint then Err := True; elsif Val < Lo or else Hi < Val then Error_Msg_N ("value outside permitted range", Expr); Err := True; end if; Set_Enumeration_Rep (Elit, Val); end if; end if; end if; end if; Next (Assoc); end loop; end if; -- Aggregate is fully processed. Now we check that a full set of -- representations was given, and that they are in range and in order. -- These checks are only done if no other errors occurred. if not Err then Min := No_Uint; Max := No_Uint; Elit := First_Literal (Enumtype); while Present (Elit) loop if No (Enumeration_Rep_Expr (Elit)) then Error_Msg_NE ("missing representation for&!", N, Elit); else Val := Enumeration_Rep (Elit); if Min = No_Uint then Min := Val; end if; if Val /= No_Uint then if Max /= No_Uint and then Val <= Max then Error_Msg_NE ("enumeration value for& not ordered!", Enumeration_Rep_Expr (Elit), Elit); end if; Max_Node := Enumeration_Rep_Expr (Elit); Max := Val; end if; -- If there is at least one literal whose representation is not -- equal to the Pos value, then note that this enumeration type -- has a non-standard representation. if Val /= Enumeration_Pos (Elit) then Set_Has_Non_Standard_Rep (Base_Type (Enumtype)); end if; end if; Next (Elit); end loop; -- Now set proper size information declare Minsize : Uint := UI_From_Int (Minimum_Size (Enumtype)); begin if Has_Size_Clause (Enumtype) then -- All OK, if size is OK now if RM_Size (Enumtype) >= Minsize then null; else -- Try if we can get by with biasing Minsize := UI_From_Int (Minimum_Size (Enumtype, Biased => True)); -- Error message if even biasing does not work if RM_Size (Enumtype) < Minsize then Error_Msg_Uint_1 := RM_Size (Enumtype); Error_Msg_Uint_2 := Max; Error_Msg_N ("previously given size (^) is too small " & "for this value (^)", Max_Node); -- If biasing worked, indicate that we now have biased rep else Set_Biased (Enumtype, Size_Clause (Enumtype), "size clause"); end if; end if; else Set_RM_Size (Enumtype, Minsize); Set_Enum_Esize (Enumtype); end if; Set_RM_Size (Base_Type (Enumtype), RM_Size (Enumtype)); Set_Esize (Base_Type (Enumtype), Esize (Enumtype)); Set_Alignment (Base_Type (Enumtype), Alignment (Enumtype)); end; end if; -- We repeat the too late test in case it froze itself if Rep_Item_Too_Late (Enumtype, N) then null; end if; end Analyze_Enumeration_Representation_Clause; ---------------------------- -- Analyze_Free_Statement -- ---------------------------- procedure Analyze_Free_Statement (N : Node_Id) is begin Analyze (Expression (N)); end Analyze_Free_Statement; --------------------------- -- Analyze_Freeze_Entity -- --------------------------- procedure Analyze_Freeze_Entity (N : Node_Id) is begin Freeze_Entity_Checks (N); end Analyze_Freeze_Entity; ----------------------------------- -- Analyze_Freeze_Generic_Entity -- ----------------------------------- procedure Analyze_Freeze_Generic_Entity (N : Node_Id) is E : constant Entity_Id := Entity (N); begin if not Is_Frozen (E) and then Has_Delayed_Aspects (E) then Analyze_Aspects_At_Freeze_Point (E); end if; Freeze_Entity_Checks (N); end Analyze_Freeze_Generic_Entity; ------------------------------------------ -- Analyze_Record_Representation_Clause -- ------------------------------------------ -- Note: we check as much as we can here, but we can't do any checks -- based on the position values (e.g. overlap checks) until freeze time -- because especially in Ada 2005 (machine scalar mode), the processing -- for non-standard bit order can substantially change the positions. -- See procedure Check_Record_Representation_Clause (called from Freeze) -- for the remainder of this processing. procedure Analyze_Record_Representation_Clause (N : Node_Id) is Ident : constant Node_Id := Identifier (N); Biased : Boolean; CC : Node_Id; Comp : Entity_Id; Fbit : Uint; Hbit : Uint := Uint_0; Lbit : Uint; Ocomp : Entity_Id; Posit : Uint; Rectype : Entity_Id; Recdef : Node_Id; function Is_Inherited (Comp : Entity_Id) return Boolean; -- True if Comp is an inherited component in a record extension ------------------ -- Is_Inherited -- ------------------ function Is_Inherited (Comp : Entity_Id) return Boolean is Comp_Base : Entity_Id; begin if Ekind (Rectype) = E_Record_Subtype then Comp_Base := Original_Record_Component (Comp); else Comp_Base := Comp; end if; return Comp_Base /= Original_Record_Component (Comp_Base); end Is_Inherited; -- Local variables Is_Record_Extension : Boolean; -- True if Rectype is a record extension CR_Pragma : Node_Id := Empty; -- Points to N_Pragma node if Complete_Representation pragma present -- Start of processing for Analyze_Record_Representation_Clause begin if Ignore_Rep_Clauses then Kill_Rep_Clause (N); return; end if; Find_Type (Ident); Rectype := Entity (Ident); if Rectype = Any_Type or else Rep_Item_Too_Early (Rectype, N) then return; else Rectype := Underlying_Type (Rectype); end if; -- First some basic error checks if not Is_Record_Type (Rectype) then Error_Msg_NE ("record type required, found}", Ident, First_Subtype (Rectype)); return; elsif Scope (Rectype) /= Current_Scope then Error_Msg_N ("type must be declared in this scope", N); return; elsif not Is_First_Subtype (Rectype) then Error_Msg_N ("cannot give record rep clause for subtype", N); return; elsif Has_Record_Rep_Clause (Rectype) then Error_Msg_N ("duplicate record rep clause ignored", N); return; elsif Rep_Item_Too_Late (Rectype, N) then return; end if; -- We know we have a first subtype, now possibly go to the anonymous -- base type to determine whether Rectype is a record extension. Recdef := Type_Definition (Declaration_Node (Base_Type (Rectype))); Is_Record_Extension := Nkind (Recdef) = N_Derived_Type_Definition and then Present (Record_Extension_Part (Recdef)); if Present (Mod_Clause (N)) then declare Loc : constant Source_Ptr := Sloc (N); M : constant Node_Id := Mod_Clause (N); P : constant List_Id := Pragmas_Before (M); AtM_Nod : Node_Id; Mod_Val : Uint; pragma Warnings (Off, Mod_Val); begin Check_Restriction (No_Obsolescent_Features, Mod_Clause (N)); if Warn_On_Obsolescent_Feature then Error_Msg_N ("?j?mod clause is an obsolescent feature (RM J.8)", N); Error_Msg_N ("\?j?use alignment attribute definition clause instead", N); end if; if Present (P) then Analyze_List (P); end if; -- In ASIS_Mode mode, expansion is disabled, but we must convert -- the Mod clause into an alignment clause anyway, so that the -- back end can compute and back-annotate properly the size and -- alignment of types that may include this record. -- This seems dubious, this destroys the source tree in a manner -- not detectable by ASIS ??? if Operating_Mode = Check_Semantics and then ASIS_Mode then AtM_Nod := Make_Attribute_Definition_Clause (Loc, Name => New_Occurrence_Of (Base_Type (Rectype), Loc), Chars => Name_Alignment, Expression => Relocate_Node (Expression (M))); Set_From_At_Mod (AtM_Nod); Insert_After (N, AtM_Nod); Mod_Val := Get_Alignment_Value (Expression (AtM_Nod)); Set_Mod_Clause (N, Empty); else -- Get the alignment value to perform error checking Mod_Val := Get_Alignment_Value (Expression (M)); end if; end; end if; -- For untagged types, clear any existing component clauses for the -- type. If the type is derived, this is what allows us to override -- a rep clause for the parent. For type extensions, the representation -- of the inherited components is inherited, so we want to keep previous -- component clauses for completeness. if not Is_Tagged_Type (Rectype) then Comp := First_Component_Or_Discriminant (Rectype); while Present (Comp) loop Set_Component_Clause (Comp, Empty); Next_Component_Or_Discriminant (Comp); end loop; end if; -- All done if no component clauses CC := First (Component_Clauses (N)); if No (CC) then return; end if; -- A representation like this applies to the base type Set_Has_Record_Rep_Clause (Base_Type (Rectype)); Set_Has_Non_Standard_Rep (Base_Type (Rectype)); Set_Has_Specified_Layout (Base_Type (Rectype)); -- Process the component clauses while Present (CC) loop -- Pragma if Nkind (CC) = N_Pragma then Analyze (CC); -- The only pragma of interest is Complete_Representation if Pragma_Name (CC) = Name_Complete_Representation then CR_Pragma := CC; end if; -- Processing for real component clause else Posit := Static_Integer (Position (CC)); Fbit := Static_Integer (First_Bit (CC)); Lbit := Static_Integer (Last_Bit (CC)); if Posit /= No_Uint and then Fbit /= No_Uint and then Lbit /= No_Uint then if Posit < 0 then Error_Msg_N ("position cannot be negative", Position (CC)); elsif Fbit < 0 then Error_Msg_N ("first bit cannot be negative", First_Bit (CC)); -- The Last_Bit specified in a component clause must not be -- less than the First_Bit minus one (RM-13.5.1(10)). elsif Lbit < Fbit - 1 then Error_Msg_N ("last bit cannot be less than first bit minus one", Last_Bit (CC)); -- Values look OK, so find the corresponding record component -- Even though the syntax allows an attribute reference for -- implementation-defined components, GNAT does not allow the -- tag to get an explicit position. elsif Nkind (Component_Name (CC)) = N_Attribute_Reference then if Attribute_Name (Component_Name (CC)) = Name_Tag then Error_Msg_N ("position of tag cannot be specified", CC); else Error_Msg_N ("illegal component name", CC); end if; else Comp := First_Entity (Rectype); while Present (Comp) loop exit when Chars (Comp) = Chars (Component_Name (CC)); Next_Entity (Comp); end loop; if No (Comp) then -- Maybe component of base type that is absent from -- statically constrained first subtype. Comp := First_Entity (Base_Type (Rectype)); while Present (Comp) loop exit when Chars (Comp) = Chars (Component_Name (CC)); Next_Entity (Comp); end loop; end if; if No (Comp) then Error_Msg_N ("component clause is for non-existent field", CC); -- Ada 2012 (AI05-0026): Any name that denotes a -- discriminant of an object of an unchecked union type -- shall not occur within a record_representation_clause. -- The general restriction of using record rep clauses on -- Unchecked_Union types has now been lifted. Since it is -- possible to introduce a record rep clause which mentions -- the discriminant of an Unchecked_Union in non-Ada 2012 -- code, this check is applied to all versions of the -- language. elsif Ekind (Comp) = E_Discriminant and then Is_Unchecked_Union (Rectype) then Error_Msg_N ("cannot reference discriminant of unchecked union", Component_Name (CC)); elsif Is_Record_Extension and then Is_Inherited (Comp) then Error_Msg_NE ("component clause not allowed for inherited " & "component&", CC, Comp); elsif Present (Component_Clause (Comp)) then -- Diagnose duplicate rep clause, or check consistency -- if this is an inherited component. In a double fault, -- there may be a duplicate inconsistent clause for an -- inherited component. if Scope (Original_Record_Component (Comp)) = Rectype or else Parent (Component_Clause (Comp)) = N then Error_Msg_Sloc := Sloc (Component_Clause (Comp)); Error_Msg_N ("component clause previously given#", CC); else declare Rep1 : constant Node_Id := Component_Clause (Comp); begin if Intval (Position (Rep1)) /= Intval (Position (CC)) or else Intval (First_Bit (Rep1)) /= Intval (First_Bit (CC)) or else Intval (Last_Bit (Rep1)) /= Intval (Last_Bit (CC)) then Error_Msg_N ("component clause inconsistent with " & "representation of ancestor", CC); elsif Warn_On_Redundant_Constructs then Error_Msg_N ("?r?redundant confirming component clause " & "for component!", CC); end if; end; end if; -- Normal case where this is the first component clause we -- have seen for this entity, so set it up properly. else -- Make reference for field in record rep clause and set -- appropriate entity field in the field identifier. Generate_Reference (Comp, Component_Name (CC), Set_Ref => False); Set_Entity (Component_Name (CC), Comp); -- Update Fbit and Lbit to the actual bit number Fbit := Fbit + UI_From_Int (SSU) * Posit; Lbit := Lbit + UI_From_Int (SSU) * Posit; if Has_Size_Clause (Rectype) and then RM_Size (Rectype) <= Lbit then Error_Msg_N ("bit number out of range of specified size", Last_Bit (CC)); else Set_Component_Clause (Comp, CC); Set_Component_Bit_Offset (Comp, Fbit); Set_Esize (Comp, 1 + (Lbit - Fbit)); Set_Normalized_First_Bit (Comp, Fbit mod SSU); Set_Normalized_Position (Comp, Fbit / SSU); if Warn_On_Overridden_Size and then Has_Size_Clause (Etype (Comp)) and then RM_Size (Etype (Comp)) /= Esize (Comp) then Error_Msg_NE ("?S?component size overrides size clause for&", Component_Name (CC), Etype (Comp)); end if; -- This information is also set in the corresponding -- component of the base type, found by accessing the -- Original_Record_Component link if it is present. Ocomp := Original_Record_Component (Comp); if Hbit < Lbit then Hbit := Lbit; end if; Check_Size (Component_Name (CC), Etype (Comp), Esize (Comp), Biased); Set_Biased (Comp, First_Node (CC), "component clause", Biased); if Present (Ocomp) then Set_Component_Clause (Ocomp, CC); Set_Component_Bit_Offset (Ocomp, Fbit); Set_Normalized_First_Bit (Ocomp, Fbit mod SSU); Set_Normalized_Position (Ocomp, Fbit / SSU); Set_Esize (Ocomp, 1 + (Lbit - Fbit)); Set_Normalized_Position_Max (Ocomp, Normalized_Position (Ocomp)); -- Note: we don't use Set_Biased here, because we -- already gave a warning above if needed, and we -- would get a duplicate for the same name here. Set_Has_Biased_Representation (Ocomp, Has_Biased_Representation (Comp)); end if; if Esize (Comp) < 0 then Error_Msg_N ("component size is negative", CC); end if; end if; end if; end if; end if; end if; Next (CC); end loop; -- Check missing components if Complete_Representation pragma appeared if Present (CR_Pragma) then Comp := First_Component_Or_Discriminant (Rectype); while Present (Comp) loop if No (Component_Clause (Comp)) then Error_Msg_NE ("missing component clause for &", CR_Pragma, Comp); end if; Next_Component_Or_Discriminant (Comp); end loop; -- Give missing components warning if required elsif Warn_On_Unrepped_Components then declare Num_Repped_Components : Nat := 0; Num_Unrepped_Components : Nat := 0; begin -- First count number of repped and unrepped components Comp := First_Component_Or_Discriminant (Rectype); while Present (Comp) loop if Present (Component_Clause (Comp)) then Num_Repped_Components := Num_Repped_Components + 1; else Num_Unrepped_Components := Num_Unrepped_Components + 1; end if; Next_Component_Or_Discriminant (Comp); end loop; -- We are only interested in the case where there is at least one -- unrepped component, and at least half the components have rep -- clauses. We figure that if less than half have them, then the -- partial rep clause is really intentional. If the component -- type has no underlying type set at this point (as for a generic -- formal type), we don't know enough to give a warning on the -- component. if Num_Unrepped_Components > 0 and then Num_Unrepped_Components < Num_Repped_Components then Comp := First_Component_Or_Discriminant (Rectype); while Present (Comp) loop if No (Component_Clause (Comp)) and then Comes_From_Source (Comp) and then Present (Underlying_Type (Etype (Comp))) and then (Is_Scalar_Type (Underlying_Type (Etype (Comp))) or else Size_Known_At_Compile_Time (Underlying_Type (Etype (Comp)))) and then not Has_Warnings_Off (Rectype) -- Ignore discriminant in unchecked union, since it is -- not there, and cannot have a component clause. and then (not Is_Unchecked_Union (Rectype) or else Ekind (Comp) /= E_Discriminant) then Error_Msg_Sloc := Sloc (Comp); Error_Msg_NE ("?C?no component clause given for & declared #", N, Comp); end if; Next_Component_Or_Discriminant (Comp); end loop; end if; end; end if; end Analyze_Record_Representation_Clause; ------------------------------------- -- Build_Discrete_Static_Predicate -- ------------------------------------- procedure Build_Discrete_Static_Predicate (Typ : Entity_Id; Expr : Node_Id; Nam : Name_Id) is Loc : constant Source_Ptr := Sloc (Expr); Non_Static : exception; -- Raised if something non-static is found Btyp : constant Entity_Id := Base_Type (Typ); BLo : constant Uint := Expr_Value (Type_Low_Bound (Btyp)); BHi : constant Uint := Expr_Value (Type_High_Bound (Btyp)); -- Low bound and high bound value of base type of Typ TLo : Uint; THi : Uint; -- Bounds for constructing the static predicate. We use the bound of the -- subtype if it is static, otherwise the corresponding base type bound. -- Note: a non-static subtype can have a static predicate. type REnt is record Lo, Hi : Uint; end record; -- One entry in a Rlist value, a single REnt (range entry) value denotes -- one range from Lo to Hi. To represent a single value range Lo = Hi = -- value. type RList is array (Nat range <>) of REnt; -- A list of ranges. The ranges are sorted in increasing order, and are -- disjoint (there is a gap of at least one value between each range in -- the table). A value is in the set of ranges in Rlist if it lies -- within one of these ranges. False_Range : constant RList := RList'(1 .. 0 => REnt'(No_Uint, No_Uint)); -- An empty set of ranges represents a range list that can never be -- satisfied, since there are no ranges in which the value could lie, -- so it does not lie in any of them. False_Range is a canonical value -- for this empty set, but general processing should test for an Rlist -- with length zero (see Is_False predicate), since other null ranges -- may appear which must be treated as False. True_Range : constant RList := RList'(1 => REnt'(BLo, BHi)); -- Range representing True, value must be in the base range function "and" (Left : RList; Right : RList) return RList; -- And's together two range lists, returning a range list. This is a set -- intersection operation. function "or" (Left : RList; Right : RList) return RList; -- Or's together two range lists, returning a range list. This is a set -- union operation. function "not" (Right : RList) return RList; -- Returns complement of a given range list, i.e. a range list -- representing all the values in TLo .. THi that are not in the input -- operand Right. function Build_Val (V : Uint) return Node_Id; -- Return an analyzed N_Identifier node referencing this value, suitable -- for use as an entry in the Static_Discrte_Predicate list. This node -- is typed with the base type. function Build_Range (Lo : Uint; Hi : Uint) return Node_Id; -- Return an analyzed N_Range node referencing this range, suitable for -- use as an entry in the Static_Discrete_Predicate list. This node is -- typed with the base type. function Get_RList (Exp : Node_Id) return RList; -- This is a recursive routine that converts the given expression into a -- list of ranges, suitable for use in building the static predicate. function Is_False (R : RList) return Boolean; pragma Inline (Is_False); -- Returns True if the given range list is empty, and thus represents a -- False list of ranges that can never be satisfied. function Is_True (R : RList) return Boolean; -- Returns True if R trivially represents the True predicate by having a -- single range from BLo to BHi. function Is_Type_Ref (N : Node_Id) return Boolean; pragma Inline (Is_Type_Ref); -- Returns if True if N is a reference to the type for the predicate in -- the expression (i.e. if it is an identifier whose Chars field matches -- the Nam given in the call). N must not be parenthesized, if the type -- name appears in parens, this routine will return False. function Lo_Val (N : Node_Id) return Uint; -- Given an entry from a Static_Discrete_Predicate list that is either -- a static expression or static range, gets either the expression value -- or the low bound of the range. function Hi_Val (N : Node_Id) return Uint; -- Given an entry from a Static_Discrete_Predicate list that is either -- a static expression or static range, gets either the expression value -- or the high bound of the range. function Membership_Entry (N : Node_Id) return RList; -- Given a single membership entry (range, value, or subtype), returns -- the corresponding range list. Raises Static_Error if not static. function Membership_Entries (N : Node_Id) return RList; -- Given an element on an alternatives list of a membership operation, -- returns the range list corresponding to this entry and all following -- entries (i.e. returns the "or" of this list of values). function Stat_Pred (Typ : Entity_Id) return RList; -- Given a type, if it has a static predicate, then return the predicate -- as a range list, otherwise raise Non_Static. ----------- -- "and" -- ----------- function "and" (Left : RList; Right : RList) return RList is FEnt : REnt; -- First range of result SLeft : Nat := Left'First; -- Start of rest of left entries SRight : Nat := Right'First; -- Start of rest of right entries begin -- If either range is True, return the other if Is_True (Left) then return Right; elsif Is_True (Right) then return Left; end if; -- If either range is False, return False if Is_False (Left) or else Is_False (Right) then return False_Range; end if; -- Loop to remove entries at start that are disjoint, and thus just -- get discarded from the result entirely. loop -- If no operands left in either operand, result is false if SLeft > Left'Last or else SRight > Right'Last then return False_Range; -- Discard first left operand entry if disjoint with right elsif Left (SLeft).Hi < Right (SRight).Lo then SLeft := SLeft + 1; -- Discard first right operand entry if disjoint with left elsif Right (SRight).Hi < Left (SLeft).Lo then SRight := SRight + 1; -- Otherwise we have an overlapping entry else exit; end if; end loop; -- Now we have two non-null operands, and first entries overlap. The -- first entry in the result will be the overlapping part of these -- two entries. FEnt := REnt'(Lo => UI_Max (Left (SLeft).Lo, Right (SRight).Lo), Hi => UI_Min (Left (SLeft).Hi, Right (SRight).Hi)); -- Now we can remove the entry that ended at a lower value, since its -- contribution is entirely contained in Fent. if Left (SLeft).Hi <= Right (SRight).Hi then SLeft := SLeft + 1; else SRight := SRight + 1; end if; -- Compute result by concatenating this first entry with the "and" of -- the remaining parts of the left and right operands. Note that if -- either of these is empty, "and" will yield empty, so that we will -- end up with just Fent, which is what we want in that case. return FEnt & (Left (SLeft .. Left'Last) and Right (SRight .. Right'Last)); end "and"; ----------- -- "not" -- ----------- function "not" (Right : RList) return RList is begin -- Return True if False range if Is_False (Right) then return True_Range; end if; -- Return False if True range if Is_True (Right) then return False_Range; end if; -- Here if not trivial case declare Result : RList (1 .. Right'Length + 1); -- May need one more entry for gap at beginning and end Count : Nat := 0; -- Number of entries stored in Result begin -- Gap at start if Right (Right'First).Lo > TLo then Count := Count + 1; Result (Count) := REnt'(TLo, Right (Right'First).Lo - 1); end if; -- Gaps between ranges for J in Right'First .. Right'Last - 1 loop Count := Count + 1; Result (Count) := REnt'(Right (J).Hi + 1, Right (J + 1).Lo - 1); end loop; -- Gap at end if Right (Right'Last).Hi < THi then Count := Count + 1; Result (Count) := REnt'(Right (Right'Last).Hi + 1, THi); end if; return Result (1 .. Count); end; end "not"; ---------- -- "or" -- ---------- function "or" (Left : RList; Right : RList) return RList is FEnt : REnt; -- First range of result SLeft : Nat := Left'First; -- Start of rest of left entries SRight : Nat := Right'First; -- Start of rest of right entries begin -- If either range is True, return True if Is_True (Left) or else Is_True (Right) then return True_Range; end if; -- If either range is False (empty), return the other if Is_False (Left) then return Right; elsif Is_False (Right) then return Left; end if; -- Initialize result first entry from left or right operand depending -- on which starts with the lower range. if Left (SLeft).Lo < Right (SRight).Lo then FEnt := Left (SLeft); SLeft := SLeft + 1; else FEnt := Right (SRight); SRight := SRight + 1; end if; -- This loop eats ranges from left and right operands that are -- contiguous with the first range we are gathering. loop -- Eat first entry in left operand if contiguous or overlapped by -- gathered first operand of result. if SLeft <= Left'Last and then Left (SLeft).Lo <= FEnt.Hi + 1 then FEnt.Hi := UI_Max (FEnt.Hi, Left (SLeft).Hi); SLeft := SLeft + 1; -- Eat first entry in right operand if contiguous or overlapped by -- gathered right operand of result. elsif SRight <= Right'Last and then Right (SRight).Lo <= FEnt.Hi + 1 then FEnt.Hi := UI_Max (FEnt.Hi, Right (SRight).Hi); SRight := SRight + 1; -- All done if no more entries to eat else exit; end if; end loop; -- Obtain result as the first entry we just computed, concatenated -- to the "or" of the remaining results (if one operand is empty, -- this will just concatenate with the other return FEnt & (Left (SLeft .. Left'Last) or Right (SRight .. Right'Last)); end "or"; ----------------- -- Build_Range -- ----------------- function Build_Range (Lo : Uint; Hi : Uint) return Node_Id is Result : Node_Id; begin Result := Make_Range (Loc, Low_Bound => Build_Val (Lo), High_Bound => Build_Val (Hi)); Set_Etype (Result, Btyp); Set_Analyzed (Result); return Result; end Build_Range; --------------- -- Build_Val -- --------------- function Build_Val (V : Uint) return Node_Id is Result : Node_Id; begin if Is_Enumeration_Type (Typ) then Result := Get_Enum_Lit_From_Pos (Typ, V, Loc); else Result := Make_Integer_Literal (Loc, V); end if; Set_Etype (Result, Btyp); Set_Is_Static_Expression (Result); Set_Analyzed (Result); return Result; end Build_Val; --------------- -- Get_RList -- --------------- function Get_RList (Exp : Node_Id) return RList is Op : Node_Kind; Val : Uint; begin -- Static expression can only be true or false if Is_OK_Static_Expression (Exp) then if Expr_Value (Exp) = 0 then return False_Range; else return True_Range; end if; end if; -- Otherwise test node type Op := Nkind (Exp); case Op is -- And when N_Op_And | N_And_Then => return Get_RList (Left_Opnd (Exp)) and Get_RList (Right_Opnd (Exp)); -- Or when N_Op_Or | N_Or_Else => return Get_RList (Left_Opnd (Exp)) or Get_RList (Right_Opnd (Exp)); -- Not when N_Op_Not => return not Get_RList (Right_Opnd (Exp)); -- Comparisons of type with static value when N_Op_Compare => -- Type is left operand if Is_Type_Ref (Left_Opnd (Exp)) and then Is_OK_Static_Expression (Right_Opnd (Exp)) then Val := Expr_Value (Right_Opnd (Exp)); -- Typ is right operand elsif Is_Type_Ref (Right_Opnd (Exp)) and then Is_OK_Static_Expression (Left_Opnd (Exp)) then Val := Expr_Value (Left_Opnd (Exp)); -- Invert sense of comparison case Op is when N_Op_Gt => Op := N_Op_Lt; when N_Op_Lt => Op := N_Op_Gt; when N_Op_Ge => Op := N_Op_Le; when N_Op_Le => Op := N_Op_Ge; when others => null; end case; -- Other cases are non-static else raise Non_Static; end if; -- Construct range according to comparison operation case Op is when N_Op_Eq => return RList'(1 => REnt'(Val, Val)); when N_Op_Ge => return RList'(1 => REnt'(Val, BHi)); when N_Op_Gt => return RList'(1 => REnt'(Val + 1, BHi)); when N_Op_Le => return RList'(1 => REnt'(BLo, Val)); when N_Op_Lt => return RList'(1 => REnt'(BLo, Val - 1)); when N_Op_Ne => return RList'(REnt'(BLo, Val - 1), REnt'(Val + 1, BHi)); when others => raise Program_Error; end case; -- Membership (IN) when N_In => if not Is_Type_Ref (Left_Opnd (Exp)) then raise Non_Static; end if; if Present (Right_Opnd (Exp)) then return Membership_Entry (Right_Opnd (Exp)); else return Membership_Entries (First (Alternatives (Exp))); end if; -- Negative membership (NOT IN) when N_Not_In => if not Is_Type_Ref (Left_Opnd (Exp)) then raise Non_Static; end if; if Present (Right_Opnd (Exp)) then return not Membership_Entry (Right_Opnd (Exp)); else return not Membership_Entries (First (Alternatives (Exp))); end if; -- Function call, may be call to static predicate when N_Function_Call => if Is_Entity_Name (Name (Exp)) then declare Ent : constant Entity_Id := Entity (Name (Exp)); begin if Is_Predicate_Function (Ent) or else Is_Predicate_Function_M (Ent) then return Stat_Pred (Etype (First_Formal (Ent))); end if; end; end if; -- Other function call cases are non-static raise Non_Static; -- Qualified expression, dig out the expression when N_Qualified_Expression => return Get_RList (Expression (Exp)); when N_Case_Expression => declare Alt : Node_Id; Choices : List_Id; Dep : Node_Id; begin if not Is_Entity_Name (Expression (Expr)) or else Etype (Expression (Expr)) /= Typ then Error_Msg_N ("expression must denaote subtype", Expression (Expr)); return False_Range; end if; -- Collect discrete choices in all True alternatives Choices := New_List; Alt := First (Alternatives (Exp)); while Present (Alt) loop Dep := Expression (Alt); if not Is_OK_Static_Expression (Dep) then raise Non_Static; elsif Is_True (Expr_Value (Dep)) then Append_List_To (Choices, New_Copy_List (Discrete_Choices (Alt))); end if; Next (Alt); end loop; return Membership_Entries (First (Choices)); end; -- Expression with actions: if no actions, dig out expression when N_Expression_With_Actions => if Is_Empty_List (Actions (Exp)) then return Get_RList (Expression (Exp)); else raise Non_Static; end if; -- Xor operator when N_Op_Xor => return (Get_RList (Left_Opnd (Exp)) and not Get_RList (Right_Opnd (Exp))) or (Get_RList (Right_Opnd (Exp)) and not Get_RList (Left_Opnd (Exp))); -- Any other node type is non-static when others => raise Non_Static; end case; end Get_RList; ------------ -- Hi_Val -- ------------ function Hi_Val (N : Node_Id) return Uint is begin if Is_OK_Static_Expression (N) then return Expr_Value (N); else pragma Assert (Nkind (N) = N_Range); return Expr_Value (High_Bound (N)); end if; end Hi_Val; -------------- -- Is_False -- -------------- function Is_False (R : RList) return Boolean is begin return R'Length = 0; end Is_False; ------------- -- Is_True -- ------------- function Is_True (R : RList) return Boolean is begin return R'Length = 1 and then R (R'First).Lo = BLo and then R (R'First).Hi = BHi; end Is_True; ----------------- -- Is_Type_Ref -- ----------------- function Is_Type_Ref (N : Node_Id) return Boolean is begin return Nkind (N) = N_Identifier and then Chars (N) = Nam and then Paren_Count (N) = 0; end Is_Type_Ref; ------------ -- Lo_Val -- ------------ function Lo_Val (N : Node_Id) return Uint is begin if Is_OK_Static_Expression (N) then return Expr_Value (N); else pragma Assert (Nkind (N) = N_Range); return Expr_Value (Low_Bound (N)); end if; end Lo_Val; ------------------------ -- Membership_Entries -- ------------------------ function Membership_Entries (N : Node_Id) return RList is begin if No (Next (N)) then return Membership_Entry (N); else return Membership_Entry (N) or Membership_Entries (Next (N)); end if; end Membership_Entries; ---------------------- -- Membership_Entry -- ---------------------- function Membership_Entry (N : Node_Id) return RList is Val : Uint; SLo : Uint; SHi : Uint; begin -- Range case if Nkind (N) = N_Range then if not Is_OK_Static_Expression (Low_Bound (N)) or else not Is_OK_Static_Expression (High_Bound (N)) then raise Non_Static; else SLo := Expr_Value (Low_Bound (N)); SHi := Expr_Value (High_Bound (N)); return RList'(1 => REnt'(SLo, SHi)); end if; -- Static expression case elsif Is_OK_Static_Expression (N) then Val := Expr_Value (N); return RList'(1 => REnt'(Val, Val)); -- Identifier (other than static expression) case else pragma Assert (Nkind (N) = N_Identifier); -- Type case if Is_Type (Entity (N)) then -- If type has predicates, process them if Has_Predicates (Entity (N)) then return Stat_Pred (Entity (N)); -- For static subtype without predicates, get range elsif Is_OK_Static_Subtype (Entity (N)) then SLo := Expr_Value (Type_Low_Bound (Entity (N))); SHi := Expr_Value (Type_High_Bound (Entity (N))); return RList'(1 => REnt'(SLo, SHi)); -- Any other type makes us non-static else raise Non_Static; end if; -- Any other kind of identifier in predicate (e.g. a non-static -- expression value) means this is not a static predicate. else raise Non_Static; end if; end if; end Membership_Entry; --------------- -- Stat_Pred -- --------------- function Stat_Pred (Typ : Entity_Id) return RList is begin -- Not static if type does not have static predicates if not Has_Static_Predicate (Typ) then raise Non_Static; end if; -- Otherwise we convert the predicate list to a range list declare Spred : constant List_Id := Static_Discrete_Predicate (Typ); Result : RList (1 .. List_Length (Spred)); P : Node_Id; begin P := First (Static_Discrete_Predicate (Typ)); for J in Result'Range loop Result (J) := REnt'(Lo_Val (P), Hi_Val (P)); Next (P); end loop; return Result; end; end Stat_Pred; -- Start of processing for Build_Discrete_Static_Predicate begin -- Establish bounds for the predicate if Compile_Time_Known_Value (Type_Low_Bound (Typ)) then TLo := Expr_Value (Type_Low_Bound (Typ)); else TLo := BLo; end if; if Compile_Time_Known_Value (Type_High_Bound (Typ)) then THi := Expr_Value (Type_High_Bound (Typ)); else THi := BHi; end if; -- Analyze the expression to see if it is a static predicate declare Ranges : constant RList := Get_RList (Expr); -- Range list from expression if it is static Plist : List_Id; begin -- Convert range list into a form for the static predicate. In the -- Ranges array, we just have raw ranges, these must be converted -- to properly typed and analyzed static expressions or range nodes. -- Note: here we limit ranges to the ranges of the subtype, so that -- a predicate is always false for values outside the subtype. That -- seems fine, such values are invalid anyway, and considering them -- to fail the predicate seems allowed and friendly, and furthermore -- simplifies processing for case statements and loops. Plist := New_List; for J in Ranges'Range loop declare Lo : Uint := Ranges (J).Lo; Hi : Uint := Ranges (J).Hi; begin -- Ignore completely out of range entry if Hi < TLo or else Lo > THi then null; -- Otherwise process entry else -- Adjust out of range value to subtype range if Lo < TLo then Lo := TLo; end if; if Hi > THi then Hi := THi; end if; -- Convert range into required form Append_To (Plist, Build_Range (Lo, Hi)); end if; end; end loop; -- Processing was successful and all entries were static, so now we -- can store the result as the predicate list. Set_Static_Discrete_Predicate (Typ, Plist); -- The processing for static predicates put the expression into -- canonical form as a series of ranges. It also eliminated -- duplicates and collapsed and combined ranges. We might as well -- replace the alternatives list of the right operand of the -- membership test with the static predicate list, which will -- usually be more efficient. declare New_Alts : constant List_Id := New_List; Old_Node : Node_Id; New_Node : Node_Id; begin Old_Node := First (Plist); while Present (Old_Node) loop New_Node := New_Copy (Old_Node); if Nkind (New_Node) = N_Range then Set_Low_Bound (New_Node, New_Copy (Low_Bound (Old_Node))); Set_High_Bound (New_Node, New_Copy (High_Bound (Old_Node))); end if; Append_To (New_Alts, New_Node); Next (Old_Node); end loop; -- If empty list, replace by False if Is_Empty_List (New_Alts) then Rewrite (Expr, New_Occurrence_Of (Standard_False, Loc)); -- Else replace by set membership test else Rewrite (Expr, Make_In (Loc, Left_Opnd => Make_Identifier (Loc, Nam), Right_Opnd => Empty, Alternatives => New_Alts)); -- Resolve new expression in function context Install_Formals (Predicate_Function (Typ)); Push_Scope (Predicate_Function (Typ)); Analyze_And_Resolve (Expr, Standard_Boolean); Pop_Scope; end if; end; end; -- If non-static, return doing nothing exception when Non_Static => return; end Build_Discrete_Static_Predicate; -------------------------------- -- Build_Export_Import_Pragma -- -------------------------------- function Build_Export_Import_Pragma (Asp : Node_Id; Id : Entity_Id) return Node_Id is Asp_Id : constant Aspect_Id := Get_Aspect_Id (Asp); Expr : constant Node_Id := Expression (Asp); Loc : constant Source_Ptr := Sloc (Asp); Args : List_Id; Conv : Node_Id; Conv_Arg : Node_Id; Dummy_1 : Node_Id; Dummy_2 : Node_Id; EN : Node_Id; LN : Node_Id; Prag : Node_Id; Create_Pragma : Boolean := False; -- This flag is set when the aspect form is such that it warrants the -- creation of a corresponding pragma. begin if Present (Expr) then if Error_Posted (Expr) then null; elsif Is_True (Expr_Value (Expr)) then Create_Pragma := True; end if; -- Otherwise the aspect defaults to True else Create_Pragma := True; end if; -- Nothing to do when the expression is False or is erroneous if not Create_Pragma then return Empty; end if; -- Obtain all interfacing aspects that apply to the related entity Get_Interfacing_Aspects (Iface_Asp => Asp, Conv_Asp => Conv, EN_Asp => EN, Expo_Asp => Dummy_1, Imp_Asp => Dummy_2, LN_Asp => LN); Args := New_List; -- Handle the convention argument if Present (Conv) then Conv_Arg := New_Copy_Tree (Expression (Conv)); -- Assume convention "Ada' when aspect Convention is missing else Conv_Arg := Make_Identifier (Loc, Name_Ada); end if; Append_To (Args, Make_Pragma_Argument_Association (Loc, Chars => Name_Convention, Expression => Conv_Arg)); -- Handle the entity argument Append_To (Args, Make_Pragma_Argument_Association (Loc, Chars => Name_Entity, Expression => New_Occurrence_Of (Id, Loc))); -- Handle the External_Name argument if Present (EN) then Append_To (Args, Make_Pragma_Argument_Association (Loc, Chars => Name_External_Name, Expression => New_Copy_Tree (Expression (EN)))); end if; -- Handle the Link_Name argument if Present (LN) then Append_To (Args, Make_Pragma_Argument_Association (Loc, Chars => Name_Link_Name, Expression => New_Copy_Tree (Expression (LN)))); end if; -- Generate: -- pragma Export/Import -- (Convention => /Ada, -- Entity => , -- [External_Name => ,] -- [Link_Name => ]); Prag := Make_Pragma (Loc, Pragma_Identifier => Make_Identifier (Loc, Chars (Identifier (Asp))), Pragma_Argument_Associations => Args); -- Decorate the relevant aspect and the pragma Set_Aspect_Rep_Item (Asp, Prag); Set_Corresponding_Aspect (Prag, Asp); Set_From_Aspect_Specification (Prag); Set_Parent (Prag, Asp); if Asp_Id = Aspect_Import and then Is_Subprogram (Id) then Set_Import_Pragma (Id, Prag); end if; return Prag; end Build_Export_Import_Pragma; ------------------------------- -- Build_Predicate_Functions -- ------------------------------- -- The procedures that are constructed here have the form: -- function typPredicate (Ixxx : typ) return Boolean is -- begin -- return -- typ1Predicate (typ1 (Ixxx)) -- and then typ2Predicate (typ2 (Ixxx)) -- and then ...; -- exp1 and then exp2 and then ... -- end typPredicate; -- Here exp1, and exp2 are expressions from Predicate pragmas. Note that -- this is the point at which these expressions get analyzed, providing the -- required delay, and typ1, typ2, are entities from which predicates are -- inherited. Note that we do NOT generate Check pragmas, that's because we -- use this function even if checks are off, e.g. for membership tests. -- Note that the inherited predicates are evaluated first, as required by -- AI12-0071-1. -- Note that Sem_Eval.Real_Or_String_Static_Predicate_Matches depends on -- the form of this return expression. -- If the expression has at least one Raise_Expression, then we also build -- the typPredicateM version of the function, in which any occurrence of a -- Raise_Expression is converted to "return False". procedure Build_Predicate_Functions (Typ : Entity_Id; N : Node_Id) is Loc : constant Source_Ptr := Sloc (Typ); Expr : Node_Id; -- This is the expression for the result of the function. It is -- is build by connecting the component predicates with AND THEN. Expr_M : Node_Id; -- This is the corresponding return expression for the Predicate_M -- function. It differs in that raise expressions are marked for -- special expansion (see Process_REs). Object_Name : Name_Id; -- Name for argument of Predicate procedure. Note that we use the same -- name for both predicate functions. That way the reference within the -- predicate expression is the same in both functions. Object_Entity : Entity_Id; -- Entity for argument of Predicate procedure Object_Entity_M : Entity_Id; -- Entity for argument of separate Predicate procedure when exceptions -- are present in expression. FDecl : Node_Id; -- The function declaration SId : Entity_Id; -- Its entity Raise_Expression_Present : Boolean := False; -- Set True if Expr has at least one Raise_Expression procedure Add_Condition (Cond : Node_Id); -- Append Cond to Expr using "and then" (or just copy Cond to Expr if -- Expr is empty). procedure Add_Predicates; -- Appends expressions for any Predicate pragmas in the rep item chain -- Typ to Expr. Note that we look only at items for this exact entity. -- Inheritance of predicates for the parent type is done by calling the -- Predicate_Function of the parent type, using Add_Call above. procedure Add_Call (T : Entity_Id); -- Includes a call to the predicate function for type T in Expr if T -- has predicates and Predicate_Function (T) is non-empty. function Process_RE (N : Node_Id) return Traverse_Result; -- Used in Process REs, tests if node N is a raise expression, and if -- so, marks it to be converted to return False. procedure Process_REs is new Traverse_Proc (Process_RE); -- Marks any raise expressions in Expr_M to return False function Test_RE (N : Node_Id) return Traverse_Result; -- Used in Test_REs, tests one node for being a raise expression, and if -- so sets Raise_Expression_Present True. procedure Test_REs is new Traverse_Proc (Test_RE); -- Tests to see if Expr contains any raise expressions -------------- -- Add_Call -- -------------- procedure Add_Call (T : Entity_Id) is Exp : Node_Id; begin if Present (T) and then Present (Predicate_Function (T)) then Set_Has_Predicates (Typ); -- Build the call to the predicate function of T Exp := Make_Predicate_Call (T, Convert_To (T, Make_Identifier (Loc, Object_Name))); -- "and"-in the call to evolving expression Add_Condition (Exp); -- Output info message on inheritance if required. Note we do not -- give this information for generic actual types, since it is -- unwelcome noise in that case in instantiations. We also -- generally suppress the message in instantiations, and also -- if it involves internal names. if Opt.List_Inherited_Aspects and then not Is_Generic_Actual_Type (Typ) and then Instantiation_Depth (Sloc (Typ)) = 0 and then not Is_Internal_Name (Chars (T)) and then not Is_Internal_Name (Chars (Typ)) then Error_Msg_Sloc := Sloc (Predicate_Function (T)); Error_Msg_Node_2 := T; Error_Msg_N ("info: & inherits predicate from & #?L?", Typ); end if; end if; end Add_Call; ------------------- -- Add_Condition -- ------------------- procedure Add_Condition (Cond : Node_Id) is begin -- This is the first predicate expression if No (Expr) then Expr := Cond; -- Otherwise concatenate to the existing predicate expressions by -- using "and then". else Expr := Make_And_Then (Loc, Left_Opnd => Relocate_Node (Expr), Right_Opnd => Cond); end if; end Add_Condition; -------------------- -- Add_Predicates -- -------------------- procedure Add_Predicates is procedure Add_Predicate (Prag : Node_Id); -- Concatenate the expression of predicate pragma Prag to Expr by -- using a short circuit "and then" operator. ------------------- -- Add_Predicate -- ------------------- procedure Add_Predicate (Prag : Node_Id) is procedure Replace_Type_Reference (N : Node_Id); -- Replace a single occurrence N of the subtype name with a -- reference to the formal of the predicate function. N can be an -- identifier referencing the subtype, or a selected component, -- representing an appropriately qualified occurrence of the -- subtype name. procedure Replace_Type_References is new Replace_Type_References_Generic (Replace_Type_Reference); -- Traverse an expression changing every occurrence of an -- identifier whose name matches the name of the subtype with a -- reference to the formal parameter of the predicate function. ---------------------------- -- Replace_Type_Reference -- ---------------------------- procedure Replace_Type_Reference (N : Node_Id) is begin Rewrite (N, Make_Identifier (Sloc (N), Object_Name)); -- Use the Sloc of the usage name, not the defining name Set_Etype (N, Typ); Set_Entity (N, Object_Entity); -- We want to treat the node as if it comes from source, so -- that ASIS will not ignore it. Set_Comes_From_Source (N, True); end Replace_Type_Reference; -- Local variables Asp : constant Node_Id := Corresponding_Aspect (Prag); Arg1 : Node_Id; Arg2 : Node_Id; -- Start of processing for Add_Predicate begin -- Extract the arguments of the pragma. The expression itself -- is copied for use in the predicate function, to preserve the -- original version for ASIS use. Arg1 := First (Pragma_Argument_Associations (Prag)); Arg2 := Next (Arg1); Arg1 := Get_Pragma_Arg (Arg1); Arg2 := New_Copy_Tree (Get_Pragma_Arg (Arg2)); -- When the predicate pragma applies to the current type or its -- full view, replace all occurrences of the subtype name with -- references to the formal parameter of the predicate function. if Entity (Arg1) = Typ or else Full_View (Entity (Arg1)) = Typ then Replace_Type_References (Arg2, Typ); -- If the predicate pragma comes from an aspect, replace the -- saved expression because we need the subtype references -- replaced for the calls to Preanalyze_Spec_Expression in -- Check_Aspect_At_xxx routines. if Present (Asp) then Set_Entity (Identifier (Asp), New_Copy_Tree (Arg2)); end if; -- "and"-in the Arg2 condition to evolving expression Add_Condition (Relocate_Node (Arg2)); end if; end Add_Predicate; -- Local variables Ritem : Node_Id; -- Start of processing for Add_Predicates begin Ritem := First_Rep_Item (Typ); while Present (Ritem) loop if Nkind (Ritem) = N_Pragma and then Pragma_Name (Ritem) = Name_Predicate then Add_Predicate (Ritem); -- If the type is declared in an inner package it may be frozen -- outside of the package, and the generated pragma has not been -- analyzed yet, so capture the expression for the predicate -- function at this point. elsif Nkind (Ritem) = N_Aspect_Specification and then Present (Aspect_Rep_Item (Ritem)) and then Scope (Typ) /= Current_Scope then declare Prag : constant Node_Id := Aspect_Rep_Item (Ritem); begin if Nkind (Prag) = N_Pragma and then Pragma_Name (Prag) = Name_Predicate then Add_Predicate (Prag); end if; end; end if; Next_Rep_Item (Ritem); end loop; end Add_Predicates; ---------------- -- Process_RE -- ---------------- function Process_RE (N : Node_Id) return Traverse_Result is begin if Nkind (N) = N_Raise_Expression then Set_Convert_To_Return_False (N); return Skip; else return OK; end if; end Process_RE; ------------- -- Test_RE -- ------------- function Test_RE (N : Node_Id) return Traverse_Result is begin if Nkind (N) = N_Raise_Expression then Raise_Expression_Present := True; return Abandon; else return OK; end if; end Test_RE; -- Local variables Save_Ghost_Mode : constant Ghost_Mode_Type := Ghost_Mode; -- Start of processing for Build_Predicate_Functions begin -- Return if already built or if type does not have predicates SId := Predicate_Function (Typ); if not Has_Predicates (Typ) or else (Present (SId) and then Has_Completion (SId)) then return; end if; -- The related type may be subject to pragma Ghost. Set the mode now to -- ensure that the predicate functions are properly marked as Ghost. Set_Ghost_Mode_From_Entity (Typ); -- Prepare to construct predicate expression Expr := Empty; if Present (SId) then FDecl := Unit_Declaration_Node (SId); else FDecl := Build_Predicate_Function_Declaration (Typ); SId := Defining_Entity (FDecl); end if; -- Recover name of formal parameter of function that replaces references -- to the type in predicate expressions. Object_Entity := Defining_Identifier (First (Parameter_Specifications (Specification (FDecl)))); Object_Name := Chars (Object_Entity); Object_Entity_M := Make_Defining_Identifier (Loc, Chars => Object_Name); -- Add predicates for ancestor if present. These must come before the -- ones for the current type, as required by AI12-0071-1. declare Atyp : constant Entity_Id := Nearest_Ancestor (Typ); begin if Present (Atyp) then Add_Call (Atyp); end if; end; -- Add Predicates for the current type Add_Predicates; -- Case where predicates are present if Present (Expr) then -- Test for raise expression present Test_REs (Expr); -- If raise expression is present, capture a copy of Expr for use -- in building the predicateM function version later on. For this -- copy we replace references to Object_Entity by Object_Entity_M. if Raise_Expression_Present then declare Map : constant Elist_Id := New_Elmt_List; New_V : Entity_Id := Empty; -- The unanalyzed expression will be copied and appear in -- both functions. Normally expressions do not declare new -- entities, but quantified expressions do, so we need to -- create new entities for their bound variables, to prevent -- multiple definitions in gigi. function Reset_Loop_Variable (N : Node_Id) return Traverse_Result; procedure Collect_Loop_Variables is new Traverse_Proc (Reset_Loop_Variable); ------------------------ -- Reset_Loop_Variable -- ------------------------ function Reset_Loop_Variable (N : Node_Id) return Traverse_Result is begin if Nkind (N) = N_Iterator_Specification then New_V := Make_Defining_Identifier (Sloc (N), Chars (Defining_Identifier (N))); Set_Defining_Identifier (N, New_V); end if; return OK; end Reset_Loop_Variable; begin Append_Elmt (Object_Entity, Map); Append_Elmt (Object_Entity_M, Map); Expr_M := New_Copy_Tree (Expr, Map => Map); Collect_Loop_Variables (Expr_M); end; end if; -- Build the main predicate function declare SIdB : constant Entity_Id := Make_Defining_Identifier (Loc, Chars => New_External_Name (Chars (Typ), "Predicate")); -- The entity for the function body Spec : Node_Id; FBody : Node_Id; begin -- The predicate function is shared between views of a type if Is_Private_Type (Typ) and then Present (Full_View (Typ)) then Set_Predicate_Function (Full_View (Typ), SId); end if; -- Mark the predicate function explicitly as Ghost because it does -- not come from source. if Ghost_Mode > None then Set_Is_Ghost_Entity (SId); end if; -- Build function body Spec := Make_Function_Specification (Loc, Defining_Unit_Name => SIdB, Parameter_Specifications => New_List ( Make_Parameter_Specification (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Object_Name), Parameter_Type => New_Occurrence_Of (Typ, Loc))), Result_Definition => New_Occurrence_Of (Standard_Boolean, Loc)); FBody := Make_Subprogram_Body (Loc, Specification => Spec, Declarations => Empty_List, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List ( Make_Simple_Return_Statement (Loc, Expression => Expr)))); -- If declaration has not been analyzed yet, Insert declaration -- before freeze node. Insert body itself after freeze node. if not Analyzed (FDecl) then Insert_Before_And_Analyze (N, FDecl); end if; Insert_After_And_Analyze (N, FBody); -- Static predicate functions are always side-effect free, and -- in most cases dynamic predicate functions are as well. Mark -- them as such whenever possible, so redundant predicate checks -- can be optimized. If there is a variable reference within the -- expression, the function is not pure. if Expander_Active then Set_Is_Pure (SId, Side_Effect_Free (Expr, Variable_Ref => True)); Set_Is_Inlined (SId); end if; end; -- Test for raise expressions present and if so build M version if Raise_Expression_Present then declare SId : constant Entity_Id := Make_Defining_Identifier (Loc, Chars => New_External_Name (Chars (Typ), "PredicateM")); -- The entity for the function spec SIdB : constant Entity_Id := Make_Defining_Identifier (Loc, Chars => New_External_Name (Chars (Typ), "PredicateM")); -- The entity for the function body Spec : Node_Id; FBody : Node_Id; FDecl : Node_Id; BTemp : Entity_Id; begin -- Mark any raise expressions for special expansion Process_REs (Expr_M); -- Build function declaration Set_Ekind (SId, E_Function); Set_Is_Predicate_Function_M (SId); Set_Predicate_Function_M (Typ, SId); -- The predicate function is shared between views of a type if Is_Private_Type (Typ) and then Present (Full_View (Typ)) then Set_Predicate_Function_M (Full_View (Typ), SId); end if; -- Mark the predicate function explicitly as Ghost because it -- does not come from source. if Ghost_Mode > None then Set_Is_Ghost_Entity (SId); end if; Spec := Make_Function_Specification (Loc, Defining_Unit_Name => SId, Parameter_Specifications => New_List ( Make_Parameter_Specification (Loc, Defining_Identifier => Object_Entity_M, Parameter_Type => New_Occurrence_Of (Typ, Loc))), Result_Definition => New_Occurrence_Of (Standard_Boolean, Loc)); FDecl := Make_Subprogram_Declaration (Loc, Specification => Spec); -- Build function body Spec := Make_Function_Specification (Loc, Defining_Unit_Name => SIdB, Parameter_Specifications => New_List ( Make_Parameter_Specification (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Object_Name), Parameter_Type => New_Occurrence_Of (Typ, Loc))), Result_Definition => New_Occurrence_Of (Standard_Boolean, Loc)); -- Build the body, we declare the boolean expression before -- doing the return, because we are not really confident of -- what happens if a return appears within a return. BTemp := Make_Defining_Identifier (Loc, Chars => New_Internal_Name ('B')); FBody := Make_Subprogram_Body (Loc, Specification => Spec, Declarations => New_List ( Make_Object_Declaration (Loc, Defining_Identifier => BTemp, Constant_Present => True, Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc), Expression => Expr_M)), Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List ( Make_Simple_Return_Statement (Loc, Expression => New_Occurrence_Of (BTemp, Loc))))); -- Insert declaration before freeze node and body after Insert_Before_And_Analyze (N, FDecl); Insert_After_And_Analyze (N, FBody); end; end if; -- See if we have a static predicate. Note that the answer may be -- yes even if we have an explicit Dynamic_Predicate present. declare PS : Boolean; EN : Node_Id; begin if not Is_Scalar_Type (Typ) and then not Is_String_Type (Typ) then PS := False; else PS := Is_Predicate_Static (Expr, Object_Name); end if; -- Case where we have a predicate-static aspect if PS then -- We don't set Has_Static_Predicate_Aspect, since we can have -- any of the three cases (Predicate, Dynamic_Predicate, or -- Static_Predicate) generating a predicate with an expression -- that is predicate-static. We just indicate that we have a -- predicate that can be treated as static. Set_Has_Static_Predicate (Typ); -- For discrete subtype, build the static predicate list if Is_Discrete_Type (Typ) then Build_Discrete_Static_Predicate (Typ, Expr, Object_Name); -- If we don't get a static predicate list, it means that we -- have a case where this is not possible, most typically in -- the case where we inherit a dynamic predicate. We do not -- consider this an error, we just leave the predicate as -- dynamic. But if we do succeed in building the list, then -- we mark the predicate as static. if No (Static_Discrete_Predicate (Typ)) then Set_Has_Static_Predicate (Typ, False); end if; -- For real or string subtype, save predicate expression elsif Is_Real_Type (Typ) or else Is_String_Type (Typ) then Set_Static_Real_Or_String_Predicate (Typ, Expr); end if; -- Case of dynamic predicate (expression is not predicate-static) else -- Again, we don't set Has_Dynamic_Predicate_Aspect, since that -- is only set if we have an explicit Dynamic_Predicate aspect -- given. Here we may simply have a Predicate aspect where the -- expression happens not to be predicate-static. -- Emit an error when the predicate is categorized as static -- but its expression is not predicate-static. -- First a little fiddling to get a nice location for the -- message. If the expression is of the form (A and then B), -- where A is an inherited predicate, then use the right -- operand for the Sloc. This avoids getting confused by a call -- to an inherited predicate with a less convenient source -- location. EN := Expr; while Nkind (EN) = N_And_Then and then Nkind (Left_Opnd (EN)) = N_Function_Call and then Is_Predicate_Function (Entity (Name (Left_Opnd (EN)))) loop EN := Right_Opnd (EN); end loop; -- Now post appropriate message if Has_Static_Predicate_Aspect (Typ) then if Is_Scalar_Type (Typ) or else Is_String_Type (Typ) then Error_Msg_F ("expression is not predicate-static (RM 3.2.4(16-22))", EN); else Error_Msg_F ("static predicate requires scalar or string type", EN); end if; end if; end if; end; end if; Ghost_Mode := Save_Ghost_Mode; end Build_Predicate_Functions; ------------------------------------------ -- Build_Predicate_Function_Declaration -- ------------------------------------------ function Build_Predicate_Function_Declaration (Typ : Entity_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (Typ); Object_Entity : constant Entity_Id := Make_Defining_Identifier (Loc, Chars => New_Internal_Name ('I')); -- The formal parameter of the function SId : constant Entity_Id := Make_Defining_Identifier (Loc, Chars => New_External_Name (Chars (Typ), "Predicate")); -- The entity for the function spec FDecl : Node_Id; Spec : Node_Id; begin Spec := Make_Function_Specification (Loc, Defining_Unit_Name => SId, Parameter_Specifications => New_List ( Make_Parameter_Specification (Loc, Defining_Identifier => Object_Entity, Parameter_Type => New_Occurrence_Of (Typ, Loc))), Result_Definition => New_Occurrence_Of (Standard_Boolean, Loc)); FDecl := Make_Subprogram_Declaration (Loc, Specification => Spec); Set_Ekind (SId, E_Function); Set_Etype (SId, Standard_Boolean); Set_Is_Internal (SId); Set_Is_Predicate_Function (SId); Set_Predicate_Function (Typ, SId); Insert_After (Parent (Typ), FDecl); Analyze (FDecl); return FDecl; end Build_Predicate_Function_Declaration; ----------------------------------------- -- Check_Aspect_At_End_Of_Declarations -- ----------------------------------------- procedure Check_Aspect_At_End_Of_Declarations (ASN : Node_Id) is Ent : constant Entity_Id := Entity (ASN); Ident : constant Node_Id := Identifier (ASN); A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident)); End_Decl_Expr : constant Node_Id := Entity (Ident); -- Expression to be analyzed at end of declarations Freeze_Expr : constant Node_Id := Expression (ASN); -- Expression from call to Check_Aspect_At_Freeze_Point T : constant Entity_Id := Etype (Freeze_Expr); -- Type required for preanalyze call Err : Boolean; -- Set False if error -- On entry to this procedure, Entity (Ident) contains a copy of the -- original expression from the aspect, saved for this purpose, and -- but Expression (Ident) is a preanalyzed copy of the expression, -- preanalyzed just after the freeze point. procedure Check_Overloaded_Name; -- For aspects whose expression is simply a name, this routine checks if -- the name is overloaded or not. If so, it verifies there is an -- interpretation that matches the entity obtained at the freeze point, -- otherwise the compiler complains. --------------------------- -- Check_Overloaded_Name -- --------------------------- procedure Check_Overloaded_Name is begin if not Is_Overloaded (End_Decl_Expr) then Err := not Is_Entity_Name (End_Decl_Expr) or else Entity (End_Decl_Expr) /= Entity (Freeze_Expr); else Err := True; declare Index : Interp_Index; It : Interp; begin Get_First_Interp (End_Decl_Expr, Index, It); while Present (It.Typ) loop if It.Nam = Entity (Freeze_Expr) then Err := False; exit; end if; Get_Next_Interp (Index, It); end loop; end; end if; end Check_Overloaded_Name; -- Start of processing for Check_Aspect_At_End_Of_Declarations begin -- In an instance we do not perform the consistency check between freeze -- point and end of declarations, because it was done already in the -- analysis of the generic. Furthermore, the delayed analysis of an -- aspect of the instance may produce spurious errors when the generic -- is a child unit that references entities in the parent (which might -- not be in scope at the freeze point of the instance). if In_Instance then return; -- Case of aspects Dimension, Dimension_System and Synchronization elsif A_Id = Aspect_Synchronization then return; -- Case of stream attributes, just have to compare entities. However, -- the expression is just a name (possibly overloaded), and there may -- be stream operations declared for unrelated types, so we just need -- to verify that one of these interpretations is the one available at -- at the freeze point. elsif A_Id = Aspect_Input or else A_Id = Aspect_Output or else A_Id = Aspect_Read or else A_Id = Aspect_Write then Analyze (End_Decl_Expr); Check_Overloaded_Name; elsif A_Id = Aspect_Variable_Indexing or else A_Id = Aspect_Constant_Indexing or else A_Id = Aspect_Default_Iterator or else A_Id = Aspect_Iterator_Element then -- Make type unfrozen before analysis, to prevent spurious errors -- about late attributes. Set_Is_Frozen (Ent, False); Analyze (End_Decl_Expr); Set_Is_Frozen (Ent, True); -- If the end of declarations comes before any other freeze -- point, the Freeze_Expr is not analyzed: no check needed. if Analyzed (Freeze_Expr) and then not In_Instance then Check_Overloaded_Name; else Err := False; end if; -- All other cases else -- Indicate that the expression comes from an aspect specification, -- which is used in subsequent analysis even if expansion is off. Set_Parent (End_Decl_Expr, ASN); -- In a generic context the aspect expressions have not been -- preanalyzed, so do it now. There are no conformance checks -- to perform in this case. if No (T) then Check_Aspect_At_Freeze_Point (ASN); return; -- The default values attributes may be defined in the private part, -- and the analysis of the expression may take place when only the -- partial view is visible. The expression must be scalar, so use -- the full view to resolve. elsif (A_Id = Aspect_Default_Value or else A_Id = Aspect_Default_Component_Value) and then Is_Private_Type (T) then Preanalyze_Spec_Expression (End_Decl_Expr, Full_View (T)); else Preanalyze_Spec_Expression (End_Decl_Expr, T); end if; Err := not Fully_Conformant_Expressions (End_Decl_Expr, Freeze_Expr); end if; -- Output error message if error. Force error on aspect specification -- even if there is an error on the expression itself. if Err then Error_Msg_NE ("!visibility of aspect for& changes after freeze point", ASN, Ent); Error_Msg_NE ("info: & is frozen here, aspects evaluated at this point??", Freeze_Node (Ent), Ent); end if; end Check_Aspect_At_End_Of_Declarations; ---------------------------------- -- Check_Aspect_At_Freeze_Point -- ---------------------------------- procedure Check_Aspect_At_Freeze_Point (ASN : Node_Id) is Ident : constant Node_Id := Identifier (ASN); -- Identifier (use Entity field to save expression) A_Id : constant Aspect_Id := Get_Aspect_Id (Chars (Ident)); T : Entity_Id := Empty; -- Type required for preanalyze call begin -- On entry to this procedure, Entity (Ident) contains a copy of the -- original expression from the aspect, saved for this purpose. -- On exit from this procedure Entity (Ident) is unchanged, still -- containing that copy, but Expression (Ident) is a preanalyzed copy -- of the expression, preanalyzed just after the freeze point. -- Make a copy of the expression to be preanalyzed Set_Expression (ASN, New_Copy_Tree (Entity (Ident))); -- Find type for preanalyze call case A_Id is -- No_Aspect should be impossible when No_Aspect => raise Program_Error; -- Aspects taking an optional boolean argument when Boolean_Aspects | Library_Unit_Aspects => T := Standard_Boolean; -- Aspects corresponding to attribute definition clauses when Aspect_Address => T := RTE (RE_Address); when Aspect_Attach_Handler => T := RTE (RE_Interrupt_ID); when Aspect_Bit_Order | Aspect_Scalar_Storage_Order => T := RTE (RE_Bit_Order); when Aspect_Convention => return; when Aspect_CPU => T := RTE (RE_CPU_Range); -- Default_Component_Value is resolved with the component type when Aspect_Default_Component_Value => T := Component_Type (Entity (ASN)); when Aspect_Default_Storage_Pool => T := Class_Wide_Type (RTE (RE_Root_Storage_Pool)); -- Default_Value is resolved with the type entity in question when Aspect_Default_Value => T := Entity (ASN); when Aspect_Dispatching_Domain => T := RTE (RE_Dispatching_Domain); when Aspect_External_Tag => T := Standard_String; when Aspect_External_Name => T := Standard_String; when Aspect_Link_Name => T := Standard_String; when Aspect_Priority | Aspect_Interrupt_Priority => T := Standard_Integer; when Aspect_Relative_Deadline => T := RTE (RE_Time_Span); when Aspect_Small => T := Universal_Real; -- For a simple storage pool, we have to retrieve the type of the -- pool object associated with the aspect's corresponding attribute -- definition clause. when Aspect_Simple_Storage_Pool => T := Etype (Expression (Aspect_Rep_Item (ASN))); when Aspect_Storage_Pool => T := Class_Wide_Type (RTE (RE_Root_Storage_Pool)); when Aspect_Alignment | Aspect_Component_Size | Aspect_Machine_Radix | Aspect_Object_Size | Aspect_Size | Aspect_Storage_Size | Aspect_Stream_Size | Aspect_Value_Size => T := Any_Integer; when Aspect_Linker_Section => T := Standard_String; when Aspect_Synchronization => return; -- Special case, the expression of these aspects is just an entity -- that does not need any resolution, so just analyze. when Aspect_Input | Aspect_Output | Aspect_Read | Aspect_Suppress | Aspect_Unsuppress | Aspect_Warnings | Aspect_Write => Analyze (Expression (ASN)); return; -- Same for Iterator aspects, where the expression is a function -- name. Legality rules are checked separately. when Aspect_Constant_Indexing | Aspect_Default_Iterator | Aspect_Iterator_Element | Aspect_Variable_Indexing => Analyze (Expression (ASN)); return; -- Ditto for Iterable, legality checks in Validate_Iterable_Aspect. when Aspect_Iterable => T := Entity (ASN); declare Cursor : constant Entity_Id := Get_Cursor_Type (ASN, T); Assoc : Node_Id; Expr : Node_Id; begin if Cursor = Any_Type then return; end if; Assoc := First (Component_Associations (Expression (ASN))); while Present (Assoc) loop Expr := Expression (Assoc); Analyze (Expr); if not Error_Posted (Expr) then Resolve_Iterable_Operation (Expr, Cursor, T, Chars (First (Choices (Assoc)))); end if; Next (Assoc); end loop; end; return; -- Invariant/Predicate take boolean expressions when Aspect_Dynamic_Predicate | Aspect_Invariant | Aspect_Predicate | Aspect_Static_Predicate | Aspect_Type_Invariant => T := Standard_Boolean; when Aspect_Predicate_Failure => T := Standard_String; -- Here is the list of aspects that don't require delay analysis when Aspect_Abstract_State | Aspect_Annotate | Aspect_Async_Readers | Aspect_Async_Writers | Aspect_Constant_After_Elaboration | Aspect_Contract_Cases | Aspect_Default_Initial_Condition | Aspect_Depends | Aspect_Dimension | Aspect_Dimension_System | Aspect_Effective_Reads | Aspect_Effective_Writes | Aspect_Extensions_Visible | Aspect_Ghost | Aspect_Global | Aspect_Implicit_Dereference | Aspect_Initial_Condition | Aspect_Initializes | Aspect_Obsolescent | Aspect_Part_Of | Aspect_Post | Aspect_Postcondition | Aspect_Pre | Aspect_Precondition | Aspect_Refined_Depends | Aspect_Refined_Global | Aspect_Refined_Post | Aspect_Refined_State | Aspect_SPARK_Mode | Aspect_Test_Case | Aspect_Unimplemented | Aspect_Volatile_Function => raise Program_Error; end case; -- Do the preanalyze call Preanalyze_Spec_Expression (Expression (ASN), T); end Check_Aspect_At_Freeze_Point; ----------------------------------- -- Check_Constant_Address_Clause -- ----------------------------------- procedure Check_Constant_Address_Clause (Expr : Node_Id; U_Ent : Entity_Id) is procedure Check_At_Constant_Address (Nod : Node_Id); -- Checks that the given node N represents a name whose 'Address is -- constant (in the same sense as OK_Constant_Address_Clause, i.e. the -- address value is the same at the point of declaration of U_Ent and at -- the time of elaboration of the address clause. procedure Check_Expr_Constants (Nod : Node_Id); -- Checks that Nod meets the requirements for a constant address clause -- in the sense of the enclosing procedure. procedure Check_List_Constants (Lst : List_Id); -- Check that all elements of list Lst meet the requirements for a -- constant address clause in the sense of the enclosing procedure. ------------------------------- -- Check_At_Constant_Address -- ------------------------------- procedure Check_At_Constant_Address (Nod : Node_Id) is begin if Is_Entity_Name (Nod) then if Present (Address_Clause (Entity ((Nod)))) then Error_Msg_NE ("invalid address clause for initialized object &!", Nod, U_Ent); Error_Msg_NE ("address for& cannot" & " depend on another address clause! (RM 13.1(22))!", Nod, U_Ent); elsif In_Same_Source_Unit (Entity (Nod), U_Ent) and then Sloc (U_Ent) < Sloc (Entity (Nod)) then Error_Msg_NE ("invalid address clause for initialized object &!", Nod, U_Ent); Error_Msg_Node_2 := U_Ent; Error_Msg_NE ("\& must be defined before & (RM 13.1(22))!", Nod, Entity (Nod)); end if; elsif Nkind (Nod) = N_Selected_Component then declare T : constant Entity_Id := Etype (Prefix (Nod)); begin if (Is_Record_Type (T) and then Has_Discriminants (T)) or else (Is_Access_Type (T) and then Is_Record_Type (Designated_Type (T)) and then Has_Discriminants (Designated_Type (T))) then Error_Msg_NE ("invalid address clause for initialized object &!", Nod, U_Ent); Error_Msg_N ("\address cannot depend on component" & " of discriminated record (RM 13.1(22))!", Nod); else Check_At_Constant_Address (Prefix (Nod)); end if; end; elsif Nkind (Nod) = N_Indexed_Component then Check_At_Constant_Address (Prefix (Nod)); Check_List_Constants (Expressions (Nod)); else Check_Expr_Constants (Nod); end if; end Check_At_Constant_Address; -------------------------- -- Check_Expr_Constants -- -------------------------- procedure Check_Expr_Constants (Nod : Node_Id) is Loc_U_Ent : constant Source_Ptr := Sloc (U_Ent); Ent : Entity_Id := Empty; begin if Nkind (Nod) in N_Has_Etype and then Etype (Nod) = Any_Type then return; end if; case Nkind (Nod) is when N_Empty | N_Error => return; when N_Identifier | N_Expanded_Name => Ent := Entity (Nod); -- We need to look at the original node if it is different -- from the node, since we may have rewritten things and -- substituted an identifier representing the rewrite. if Original_Node (Nod) /= Nod then Check_Expr_Constants (Original_Node (Nod)); -- If the node is an object declaration without initial -- value, some code has been expanded, and the expression -- is not constant, even if the constituents might be -- acceptable, as in A'Address + offset. if Ekind (Ent) = E_Variable and then Nkind (Declaration_Node (Ent)) = N_Object_Declaration and then No (Expression (Declaration_Node (Ent))) then Error_Msg_NE ("invalid address clause for initialized object &!", Nod, U_Ent); -- If entity is constant, it may be the result of expanding -- a check. We must verify that its declaration appears -- before the object in question, else we also reject the -- address clause. elsif Ekind (Ent) = E_Constant and then In_Same_Source_Unit (Ent, U_Ent) and then Sloc (Ent) > Loc_U_Ent then Error_Msg_NE ("invalid address clause for initialized object &!", Nod, U_Ent); end if; return; end if; -- Otherwise look at the identifier and see if it is OK if Ekind_In (Ent, E_Named_Integer, E_Named_Real) or else Is_Type (Ent) then return; elsif Ekind_In (Ent, E_Constant, E_In_Parameter) then -- This is the case where we must have Ent defined before -- U_Ent. Clearly if they are in different units this -- requirement is met since the unit containing Ent is -- already processed. if not In_Same_Source_Unit (Ent, U_Ent) then return; -- Otherwise location of Ent must be before the location -- of U_Ent, that's what prior defined means. elsif Sloc (Ent) < Loc_U_Ent then return; else Error_Msg_NE ("invalid address clause for initialized object &!", Nod, U_Ent); Error_Msg_Node_2 := U_Ent; Error_Msg_NE ("\& must be defined before & (RM 13.1(22))!", Nod, Ent); end if; elsif Nkind (Original_Node (Nod)) = N_Function_Call then Check_Expr_Constants (Original_Node (Nod)); else Error_Msg_NE ("invalid address clause for initialized object &!", Nod, U_Ent); if Comes_From_Source (Ent) then Error_Msg_NE ("\reference to variable& not allowed" & " (RM 13.1(22))!", Nod, Ent); else Error_Msg_N ("non-static expression not allowed" & " (RM 13.1(22))!", Nod); end if; end if; when N_Integer_Literal => -- If this is a rewritten unchecked conversion, in a system -- where Address is an integer type, always use the base type -- for a literal value. This is user-friendly and prevents -- order-of-elaboration issues with instances of unchecked -- conversion. if Nkind (Original_Node (Nod)) = N_Function_Call then Set_Etype (Nod, Base_Type (Etype (Nod))); end if; when N_Real_Literal | N_String_Literal | N_Character_Literal => return; when N_Range => Check_Expr_Constants (Low_Bound (Nod)); Check_Expr_Constants (High_Bound (Nod)); when N_Explicit_Dereference => Check_Expr_Constants (Prefix (Nod)); when N_Indexed_Component => Check_Expr_Constants (Prefix (Nod)); Check_List_Constants (Expressions (Nod)); when N_Slice => Check_Expr_Constants (Prefix (Nod)); Check_Expr_Constants (Discrete_Range (Nod)); when N_Selected_Component => Check_Expr_Constants (Prefix (Nod)); when N_Attribute_Reference => if Nam_In (Attribute_Name (Nod), Name_Address, Name_Access, Name_Unchecked_Access, Name_Unrestricted_Access) then Check_At_Constant_Address (Prefix (Nod)); else Check_Expr_Constants (Prefix (Nod)); Check_List_Constants (Expressions (Nod)); end if; when N_Aggregate => Check_List_Constants (Component_Associations (Nod)); Check_List_Constants (Expressions (Nod)); when N_Component_Association => Check_Expr_Constants (Expression (Nod)); when N_Extension_Aggregate => Check_Expr_Constants (Ancestor_Part (Nod)); Check_List_Constants (Component_Associations (Nod)); Check_List_Constants (Expressions (Nod)); when N_Null => return; when N_Binary_Op | N_Short_Circuit | N_Membership_Test => Check_Expr_Constants (Left_Opnd (Nod)); Check_Expr_Constants (Right_Opnd (Nod)); when N_Unary_Op => Check_Expr_Constants (Right_Opnd (Nod)); when N_Type_Conversion | N_Qualified_Expression | N_Allocator | N_Unchecked_Type_Conversion => Check_Expr_Constants (Expression (Nod)); when N_Function_Call => if not Is_Pure (Entity (Name (Nod))) then Error_Msg_NE ("invalid address clause for initialized object &!", Nod, U_Ent); Error_Msg_NE ("\function & is not pure (RM 13.1(22))!", Nod, Entity (Name (Nod))); else Check_List_Constants (Parameter_Associations (Nod)); end if; when N_Parameter_Association => Check_Expr_Constants (Explicit_Actual_Parameter (Nod)); when others => Error_Msg_NE ("invalid address clause for initialized object &!", Nod, U_Ent); Error_Msg_NE ("\must be constant defined before& (RM 13.1(22))!", Nod, U_Ent); end case; end Check_Expr_Constants; -------------------------- -- Check_List_Constants -- -------------------------- procedure Check_List_Constants (Lst : List_Id) is Nod1 : Node_Id; begin if Present (Lst) then Nod1 := First (Lst); while Present (Nod1) loop Check_Expr_Constants (Nod1); Next (Nod1); end loop; end if; end Check_List_Constants; -- Start of processing for Check_Constant_Address_Clause begin -- If rep_clauses are to be ignored, no need for legality checks. In -- particular, no need to pester user about rep clauses that violate the -- rule on constant addresses, given that these clauses will be removed -- by Freeze before they reach the back end. Similarly in CodePeer mode, -- we want to relax these checks. if not Ignore_Rep_Clauses and not CodePeer_Mode then Check_Expr_Constants (Expr); end if; end Check_Constant_Address_Clause; --------------------------- -- Check_Pool_Size_Clash -- --------------------------- procedure Check_Pool_Size_Clash (Ent : Entity_Id; SP, SS : Node_Id) is Post : Node_Id; begin -- We need to find out which one came first. Note that in the case of -- aspects mixed with pragmas there are cases where the processing order -- is reversed, which is why we do the check here. if Sloc (SP) < Sloc (SS) then Error_Msg_Sloc := Sloc (SP); Post := SS; Error_Msg_NE ("Storage_Pool previously given for&#", Post, Ent); else Error_Msg_Sloc := Sloc (SS); Post := SP; Error_Msg_NE ("Storage_Size previously given for&#", Post, Ent); end if; Error_Msg_N ("\cannot have Storage_Size and Storage_Pool (RM 13.11(3))", Post); end Check_Pool_Size_Clash; ---------------------------------------- -- Check_Record_Representation_Clause -- ---------------------------------------- procedure Check_Record_Representation_Clause (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Ident : constant Node_Id := Identifier (N); Rectype : Entity_Id; Fent : Entity_Id; CC : Node_Id; Fbit : Uint; Lbit : Uint; Hbit : Uint := Uint_0; Comp : Entity_Id; Pcomp : Entity_Id; Max_Bit_So_Far : Uint; -- Records the maximum bit position so far. If all field positions -- are monotonically increasing, then we can skip the circuit for -- checking for overlap, since no overlap is possible. Tagged_Parent : Entity_Id := Empty; -- This is set in the case of a derived tagged type for which we have -- Is_Fully_Repped_Tagged_Type True (indicating that all components are -- positioned by record representation clauses). In this case we must -- check for overlap between components of this tagged type, and the -- components of its parent. Tagged_Parent will point to this parent -- type. For all other cases Tagged_Parent is left set to Empty. Parent_Last_Bit : Uint; -- Relevant only if Tagged_Parent is set, Parent_Last_Bit indicates the -- last bit position for any field in the parent type. We only need to -- check overlap for fields starting below this point. Overlap_Check_Required : Boolean; -- Used to keep track of whether or not an overlap check is required Overlap_Detected : Boolean := False; -- Set True if an overlap is detected Ccount : Natural := 0; -- Number of component clauses in record rep clause procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id); -- Given two entities for record components or discriminants, checks -- if they have overlapping component clauses and issues errors if so. procedure Find_Component; -- Finds component entity corresponding to current component clause (in -- CC), and sets Comp to the entity, and Fbit/Lbit to the zero origin -- start/stop bits for the field. If there is no matching component or -- if the matching component does not have a component clause, then -- that's an error and Comp is set to Empty, but no error message is -- issued, since the message was already given. Comp is also set to -- Empty if the current "component clause" is in fact a pragma. ----------------------------- -- Check_Component_Overlap -- ----------------------------- procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id) is CC1 : constant Node_Id := Component_Clause (C1_Ent); CC2 : constant Node_Id := Component_Clause (C2_Ent); begin if Present (CC1) and then Present (CC2) then -- Exclude odd case where we have two tag components in the same -- record, both at location zero. This seems a bit strange, but -- it seems to happen in some circumstances, perhaps on an error. if Nam_In (Chars (C1_Ent), Name_uTag, Name_uTag) then return; end if; -- Here we check if the two fields overlap declare S1 : constant Uint := Component_Bit_Offset (C1_Ent); S2 : constant Uint := Component_Bit_Offset (C2_Ent); E1 : constant Uint := S1 + Esize (C1_Ent); E2 : constant Uint := S2 + Esize (C2_Ent); begin if E2 <= S1 or else E1 <= S2 then null; else Error_Msg_Node_2 := Component_Name (CC2); Error_Msg_Sloc := Sloc (Error_Msg_Node_2); Error_Msg_Node_1 := Component_Name (CC1); Error_Msg_N ("component& overlaps & #", Component_Name (CC1)); Overlap_Detected := True; end if; end; end if; end Check_Component_Overlap; -------------------- -- Find_Component -- -------------------- procedure Find_Component is procedure Search_Component (R : Entity_Id); -- Search components of R for a match. If found, Comp is set ---------------------- -- Search_Component -- ---------------------- procedure Search_Component (R : Entity_Id) is begin Comp := First_Component_Or_Discriminant (R); while Present (Comp) loop -- Ignore error of attribute name for component name (we -- already gave an error message for this, so no need to -- complain here) if Nkind (Component_Name (CC)) = N_Attribute_Reference then null; else exit when Chars (Comp) = Chars (Component_Name (CC)); end if; Next_Component_Or_Discriminant (Comp); end loop; end Search_Component; -- Start of processing for Find_Component begin -- Return with Comp set to Empty if we have a pragma if Nkind (CC) = N_Pragma then Comp := Empty; return; end if; -- Search current record for matching component Search_Component (Rectype); -- If not found, maybe component of base type discriminant that is -- absent from statically constrained first subtype. if No (Comp) then Search_Component (Base_Type (Rectype)); end if; -- If no component, or the component does not reference the component -- clause in question, then there was some previous error for which -- we already gave a message, so just return with Comp Empty. if No (Comp) or else Component_Clause (Comp) /= CC then Check_Error_Detected; Comp := Empty; -- Normal case where we have a component clause else Fbit := Component_Bit_Offset (Comp); Lbit := Fbit + Esize (Comp) - 1; end if; end Find_Component; -- Start of processing for Check_Record_Representation_Clause begin Find_Type (Ident); Rectype := Entity (Ident); if Rectype = Any_Type then return; else Rectype := Underlying_Type (Rectype); end if; -- See if we have a fully repped derived tagged type declare PS : constant Entity_Id := Parent_Subtype (Rectype); begin if Present (PS) and then Is_Fully_Repped_Tagged_Type (PS) then Tagged_Parent := PS; -- Find maximum bit of any component of the parent type Parent_Last_Bit := UI_From_Int (System_Address_Size - 1); Pcomp := First_Entity (Tagged_Parent); while Present (Pcomp) loop if Ekind_In (Pcomp, E_Discriminant, E_Component) then if Component_Bit_Offset (Pcomp) /= No_Uint and then Known_Static_Esize (Pcomp) then Parent_Last_Bit := UI_Max (Parent_Last_Bit, Component_Bit_Offset (Pcomp) + Esize (Pcomp) - 1); end if; else -- Skip anonymous types generated for constrained array -- or record components. null; end if; Next_Entity (Pcomp); end loop; end if; end; -- All done if no component clauses CC := First (Component_Clauses (N)); if No (CC) then return; end if; -- If a tag is present, then create a component clause that places it -- at the start of the record (otherwise gigi may place it after other -- fields that have rep clauses). Fent := First_Entity (Rectype); if Nkind (Fent) = N_Defining_Identifier and then Chars (Fent) = Name_uTag then Set_Component_Bit_Offset (Fent, Uint_0); Set_Normalized_Position (Fent, Uint_0); Set_Normalized_First_Bit (Fent, Uint_0); Set_Normalized_Position_Max (Fent, Uint_0); Init_Esize (Fent, System_Address_Size); Set_Component_Clause (Fent, Make_Component_Clause (Loc, Component_Name => Make_Identifier (Loc, Name_uTag), Position => Make_Integer_Literal (Loc, Uint_0), First_Bit => Make_Integer_Literal (Loc, Uint_0), Last_Bit => Make_Integer_Literal (Loc, UI_From_Int (System_Address_Size)))); Ccount := Ccount + 1; end if; Max_Bit_So_Far := Uint_Minus_1; Overlap_Check_Required := False; -- Process the component clauses while Present (CC) loop Find_Component; if Present (Comp) then Ccount := Ccount + 1; -- We need a full overlap check if record positions non-monotonic if Fbit <= Max_Bit_So_Far then Overlap_Check_Required := True; end if; Max_Bit_So_Far := Lbit; -- Check bit position out of range of specified size if Has_Size_Clause (Rectype) and then RM_Size (Rectype) <= Lbit then Error_Msg_N ("bit number out of range of specified size", Last_Bit (CC)); -- Check for overlap with tag component else if Is_Tagged_Type (Rectype) and then Fbit < System_Address_Size then Error_Msg_NE ("component overlaps tag field of&", Component_Name (CC), Rectype); Overlap_Detected := True; end if; if Hbit < Lbit then Hbit := Lbit; end if; end if; -- Check parent overlap if component might overlap parent field if Present (Tagged_Parent) and then Fbit <= Parent_Last_Bit then Pcomp := First_Component_Or_Discriminant (Tagged_Parent); while Present (Pcomp) loop if not Is_Tag (Pcomp) and then Chars (Pcomp) /= Name_uParent then Check_Component_Overlap (Comp, Pcomp); end if; Next_Component_Or_Discriminant (Pcomp); end loop; end if; end if; Next (CC); end loop; -- Now that we have processed all the component clauses, check for -- overlap. We have to leave this till last, since the components can -- appear in any arbitrary order in the representation clause. -- We do not need this check if all specified ranges were monotonic, -- as recorded by Overlap_Check_Required being False at this stage. -- This first section checks if there are any overlapping entries at -- all. It does this by sorting all entries and then seeing if there are -- any overlaps. If there are none, then that is decisive, but if there -- are overlaps, they may still be OK (they may result from fields in -- different variants). if Overlap_Check_Required then Overlap_Check1 : declare OC_Fbit : array (0 .. Ccount) of Uint; -- First-bit values for component clauses, the value is the offset -- of the first bit of the field from start of record. The zero -- entry is for use in sorting. OC_Lbit : array (0 .. Ccount) of Uint; -- Last-bit values for component clauses, the value is the offset -- of the last bit of the field from start of record. The zero -- entry is for use in sorting. OC_Count : Natural := 0; -- Count of entries in OC_Fbit and OC_Lbit function OC_Lt (Op1, Op2 : Natural) return Boolean; -- Compare routine for Sort procedure OC_Move (From : Natural; To : Natural); -- Move routine for Sort package Sorting is new GNAT.Heap_Sort_G (OC_Move, OC_Lt); ----------- -- OC_Lt -- ----------- function OC_Lt (Op1, Op2 : Natural) return Boolean is begin return OC_Fbit (Op1) < OC_Fbit (Op2); end OC_Lt; ------------- -- OC_Move -- ------------- procedure OC_Move (From : Natural; To : Natural) is begin OC_Fbit (To) := OC_Fbit (From); OC_Lbit (To) := OC_Lbit (From); end OC_Move; -- Start of processing for Overlap_Check begin CC := First (Component_Clauses (N)); while Present (CC) loop -- Exclude component clause already marked in error if not Error_Posted (CC) then Find_Component; if Present (Comp) then OC_Count := OC_Count + 1; OC_Fbit (OC_Count) := Fbit; OC_Lbit (OC_Count) := Lbit; end if; end if; Next (CC); end loop; Sorting.Sort (OC_Count); Overlap_Check_Required := False; for J in 1 .. OC_Count - 1 loop if OC_Lbit (J) >= OC_Fbit (J + 1) then Overlap_Check_Required := True; exit; end if; end loop; end Overlap_Check1; end if; -- If Overlap_Check_Required is still True, then we have to do the full -- scale overlap check, since we have at least two fields that do -- overlap, and we need to know if that is OK since they are in -- different variant, or whether we have a definite problem. if Overlap_Check_Required then Overlap_Check2 : declare C1_Ent, C2_Ent : Entity_Id; -- Entities of components being checked for overlap Clist : Node_Id; -- Component_List node whose Component_Items are being checked Citem : Node_Id; -- Component declaration for component being checked begin C1_Ent := First_Entity (Base_Type (Rectype)); -- Loop through all components in record. For each component check -- for overlap with any of the preceding elements on the component -- list containing the component and also, if the component is in -- a variant, check against components outside the case structure. -- This latter test is repeated recursively up the variant tree. Main_Component_Loop : while Present (C1_Ent) loop if not Ekind_In (C1_Ent, E_Component, E_Discriminant) then goto Continue_Main_Component_Loop; end if; -- Skip overlap check if entity has no declaration node. This -- happens with discriminants in constrained derived types. -- Possibly we are missing some checks as a result, but that -- does not seem terribly serious. if No (Declaration_Node (C1_Ent)) then goto Continue_Main_Component_Loop; end if; Clist := Parent (List_Containing (Declaration_Node (C1_Ent))); -- Loop through component lists that need checking. Check the -- current component list and all lists in variants above us. Component_List_Loop : loop -- If derived type definition, go to full declaration -- If at outer level, check discriminants if there are any. if Nkind (Clist) = N_Derived_Type_Definition then Clist := Parent (Clist); end if; -- Outer level of record definition, check discriminants if Nkind_In (Clist, N_Full_Type_Declaration, N_Private_Type_Declaration) then if Has_Discriminants (Defining_Identifier (Clist)) then C2_Ent := First_Discriminant (Defining_Identifier (Clist)); while Present (C2_Ent) loop exit when C1_Ent = C2_Ent; Check_Component_Overlap (C1_Ent, C2_Ent); Next_Discriminant (C2_Ent); end loop; end if; -- Record extension case elsif Nkind (Clist) = N_Derived_Type_Definition then Clist := Empty; -- Otherwise check one component list else Citem := First (Component_Items (Clist)); while Present (Citem) loop if Nkind (Citem) = N_Component_Declaration then C2_Ent := Defining_Identifier (Citem); exit when C1_Ent = C2_Ent; Check_Component_Overlap (C1_Ent, C2_Ent); end if; Next (Citem); end loop; end if; -- Check for variants above us (the parent of the Clist can -- be a variant, in which case its parent is a variant part, -- and the parent of the variant part is a component list -- whose components must all be checked against the current -- component for overlap). if Nkind (Parent (Clist)) = N_Variant then Clist := Parent (Parent (Parent (Clist))); -- Check for possible discriminant part in record, this -- is treated essentially as another level in the -- recursion. For this case the parent of the component -- list is the record definition, and its parent is the -- full type declaration containing the discriminant -- specifications. elsif Nkind (Parent (Clist)) = N_Record_Definition then Clist := Parent (Parent ((Clist))); -- If neither of these two cases, we are at the top of -- the tree. else exit Component_List_Loop; end if; end loop Component_List_Loop; <> Next_Entity (C1_Ent); end loop Main_Component_Loop; end Overlap_Check2; end if; -- The following circuit deals with warning on record holes (gaps). We -- skip this check if overlap was detected, since it makes sense for the -- programmer to fix this illegality before worrying about warnings. if not Overlap_Detected and Warn_On_Record_Holes then Record_Hole_Check : declare Decl : constant Node_Id := Declaration_Node (Base_Type (Rectype)); -- Full declaration of record type procedure Check_Component_List (CL : Node_Id; Sbit : Uint; DS : List_Id); -- Check component list CL for holes. The starting bit should be -- Sbit. which is zero for the main record component list and set -- appropriately for recursive calls for variants. DS is set to -- a list of discriminant specifications to be included in the -- consideration of components. It is No_List if none to consider. -------------------------- -- Check_Component_List -- -------------------------- procedure Check_Component_List (CL : Node_Id; Sbit : Uint; DS : List_Id) is Compl : Integer; begin Compl := Integer (List_Length (Component_Items (CL))); if DS /= No_List then Compl := Compl + Integer (List_Length (DS)); end if; declare Comps : array (Natural range 0 .. Compl) of Entity_Id; -- Gather components (zero entry is for sort routine) Ncomps : Natural := 0; -- Number of entries stored in Comps (starting at Comps (1)) Citem : Node_Id; -- One component item or discriminant specification Nbit : Uint; -- Starting bit for next component CEnt : Entity_Id; -- Component entity Variant : Node_Id; -- One variant function Lt (Op1, Op2 : Natural) return Boolean; -- Compare routine for Sort procedure Move (From : Natural; To : Natural); -- Move routine for Sort package Sorting is new GNAT.Heap_Sort_G (Move, Lt); -------- -- Lt -- -------- function Lt (Op1, Op2 : Natural) return Boolean is begin return Component_Bit_Offset (Comps (Op1)) < Component_Bit_Offset (Comps (Op2)); end Lt; ---------- -- Move -- ---------- procedure Move (From : Natural; To : Natural) is begin Comps (To) := Comps (From); end Move; begin -- Gather discriminants into Comp if DS /= No_List then Citem := First (DS); while Present (Citem) loop if Nkind (Citem) = N_Discriminant_Specification then declare Ent : constant Entity_Id := Defining_Identifier (Citem); begin if Ekind (Ent) = E_Discriminant then Ncomps := Ncomps + 1; Comps (Ncomps) := Ent; end if; end; end if; Next (Citem); end loop; end if; -- Gather component entities into Comp Citem := First (Component_Items (CL)); while Present (Citem) loop if Nkind (Citem) = N_Component_Declaration then Ncomps := Ncomps + 1; Comps (Ncomps) := Defining_Identifier (Citem); end if; Next (Citem); end loop; -- Now sort the component entities based on the first bit. -- Note we already know there are no overlapping components. Sorting.Sort (Ncomps); -- Loop through entries checking for holes Nbit := Sbit; for J in 1 .. Ncomps loop CEnt := Comps (J); Error_Msg_Uint_1 := Component_Bit_Offset (CEnt) - Nbit; if Error_Msg_Uint_1 > 0 then Error_Msg_NE ("?H?^-bit gap before component&", Component_Name (Component_Clause (CEnt)), CEnt); end if; Nbit := Component_Bit_Offset (CEnt) + Esize (CEnt); end loop; -- Process variant parts recursively if present if Present (Variant_Part (CL)) then Variant := First (Variants (Variant_Part (CL))); while Present (Variant) loop Check_Component_List (Component_List (Variant), Nbit, No_List); Next (Variant); end loop; end if; end; end Check_Component_List; -- Start of processing for Record_Hole_Check begin declare Sbit : Uint; begin if Is_Tagged_Type (Rectype) then Sbit := UI_From_Int (System_Address_Size); else Sbit := Uint_0; end if; if Nkind (Decl) = N_Full_Type_Declaration and then Nkind (Type_Definition (Decl)) = N_Record_Definition then Check_Component_List (Component_List (Type_Definition (Decl)), Sbit, Discriminant_Specifications (Decl)); end if; end; end Record_Hole_Check; end if; -- For records that have component clauses for all components, and whose -- size is less than or equal to 32, we need to know the size in the -- front end to activate possible packed array processing where the -- component type is a record. -- At this stage Hbit + 1 represents the first unused bit from all the -- component clauses processed, so if the component clauses are -- complete, then this is the length of the record. -- For records longer than System.Storage_Unit, and for those where not -- all components have component clauses, the back end determines the -- length (it may for example be appropriate to round up the size -- to some convenient boundary, based on alignment considerations, etc). if Unknown_RM_Size (Rectype) and then Hbit + 1 <= 32 then -- Nothing to do if at least one component has no component clause Comp := First_Component_Or_Discriminant (Rectype); while Present (Comp) loop exit when No (Component_Clause (Comp)); Next_Component_Or_Discriminant (Comp); end loop; -- If we fall out of loop, all components have component clauses -- and so we can set the size to the maximum value. if No (Comp) then Set_RM_Size (Rectype, Hbit + 1); end if; end if; end Check_Record_Representation_Clause; ---------------- -- Check_Size -- ---------------- procedure Check_Size (N : Node_Id; T : Entity_Id; Siz : Uint; Biased : out Boolean) is procedure Size_Too_Small_Error (Min_Siz : Uint); -- Emit an error concerning illegal size Siz. Min_Siz denotes the -- minimum size. -------------------------- -- Size_Too_Small_Error -- -------------------------- procedure Size_Too_Small_Error (Min_Siz : Uint) is begin -- This error is suppressed in ASIS mode to allow for different ASIS -- back ends or ASIS-based tools to query the illegal clause. if not ASIS_Mode then Error_Msg_Uint_1 := Min_Siz; Error_Msg_NE ("size for& too small, minimum allowed is ^", N, T); end if; end Size_Too_Small_Error; -- Local variables UT : constant Entity_Id := Underlying_Type (T); M : Uint; -- Start of processing for Check_Size begin Biased := False; -- Reject patently improper size values if Is_Elementary_Type (T) and then Siz > UI_From_Int (Int'Last) then Error_Msg_N ("Size value too large for elementary type", N); if Nkind (Original_Node (N)) = N_Op_Expon then Error_Msg_N ("\maybe '* was meant, rather than '*'*", Original_Node (N)); end if; end if; -- Dismiss generic types if Is_Generic_Type (T) or else Is_Generic_Type (UT) or else Is_Generic_Type (Root_Type (UT)) then return; -- Guard against previous errors elsif No (UT) or else UT = Any_Type then Check_Error_Detected; return; -- Check case of bit packed array elsif Is_Array_Type (UT) and then Known_Static_Component_Size (UT) and then Is_Bit_Packed_Array (UT) then declare Asiz : Uint; Indx : Node_Id; Ityp : Entity_Id; begin Asiz := Component_Size (UT); Indx := First_Index (UT); loop Ityp := Etype (Indx); -- If non-static bound, then we are not in the business of -- trying to check the length, and indeed an error will be -- issued elsewhere, since sizes of non-static array types -- cannot be set implicitly or explicitly. if not Is_OK_Static_Subtype (Ityp) then return; end if; -- Otherwise accumulate next dimension Asiz := Asiz * (Expr_Value (Type_High_Bound (Ityp)) - Expr_Value (Type_Low_Bound (Ityp)) + Uint_1); Next_Index (Indx); exit when No (Indx); end loop; if Asiz <= Siz then return; else Size_Too_Small_Error (Asiz); Set_Esize (T, Asiz); Set_RM_Size (T, Asiz); end if; end; -- All other composite types are ignored elsif Is_Composite_Type (UT) then return; -- For fixed-point types, don't check minimum if type is not frozen, -- since we don't know all the characteristics of the type that can -- affect the size (e.g. a specified small) till freeze time. elsif Is_Fixed_Point_Type (UT) and then not Is_Frozen (UT) then null; -- Cases for which a minimum check is required else -- Ignore if specified size is correct for the type if Known_Esize (UT) and then Siz = Esize (UT) then return; end if; -- Otherwise get minimum size M := UI_From_Int (Minimum_Size (UT)); if Siz < M then -- Size is less than minimum size, but one possibility remains -- that we can manage with the new size if we bias the type. M := UI_From_Int (Minimum_Size (UT, Biased => True)); if Siz < M then Size_Too_Small_Error (M); Set_Esize (T, M); Set_RM_Size (T, M); else Biased := True; end if; end if; end if; end Check_Size; -------------------------- -- Freeze_Entity_Checks -- -------------------------- procedure Freeze_Entity_Checks (N : Node_Id) is procedure Hide_Non_Overridden_Subprograms (Typ : Entity_Id); -- Inspect the primitive operations of type Typ and hide all pairs of -- implicitly declared non-overridden non-fully conformant homographs -- (Ada RM 8.3 12.3/2). ------------------------------------- -- Hide_Non_Overridden_Subprograms -- ------------------------------------- procedure Hide_Non_Overridden_Subprograms (Typ : Entity_Id) is procedure Hide_Matching_Homographs (Subp_Id : Entity_Id; Start_Elmt : Elmt_Id); -- Inspect a list of primitive operations starting with Start_Elmt -- and find matching implicitly declared non-overridden non-fully -- conformant homographs of Subp_Id. If found, all matches along -- with Subp_Id are hidden from all visibility. function Is_Non_Overridden_Or_Null_Procedure (Subp_Id : Entity_Id) return Boolean; -- Determine whether subprogram Subp_Id is implicitly declared non- -- overridden subprogram or an implicitly declared null procedure. ------------------------------ -- Hide_Matching_Homographs -- ------------------------------ procedure Hide_Matching_Homographs (Subp_Id : Entity_Id; Start_Elmt : Elmt_Id) is Prim : Entity_Id; Prim_Elmt : Elmt_Id; begin Prim_Elmt := Start_Elmt; while Present (Prim_Elmt) loop Prim := Node (Prim_Elmt); -- The current primitive is implicitly declared non-overridden -- non-fully conformant homograph of Subp_Id. Both subprograms -- must be hidden from visibility. if Chars (Prim) = Chars (Subp_Id) and then Is_Non_Overridden_Or_Null_Procedure (Prim) and then not Fully_Conformant (Prim, Subp_Id) then Set_Is_Hidden_Non_Overridden_Subpgm (Prim); Set_Is_Immediately_Visible (Prim, False); Set_Is_Potentially_Use_Visible (Prim, False); Set_Is_Hidden_Non_Overridden_Subpgm (Subp_Id); Set_Is_Immediately_Visible (Subp_Id, False); Set_Is_Potentially_Use_Visible (Subp_Id, False); end if; Next_Elmt (Prim_Elmt); end loop; end Hide_Matching_Homographs; ----------------------------------------- -- Is_Non_Overridden_Or_Null_Procedure -- ----------------------------------------- function Is_Non_Overridden_Or_Null_Procedure (Subp_Id : Entity_Id) return Boolean is Alias_Id : Entity_Id; begin -- The subprogram is inherited (implicitly declared), it does not -- override and does not cover a primitive of an interface. if Ekind_In (Subp_Id, E_Function, E_Procedure) and then Present (Alias (Subp_Id)) and then No (Interface_Alias (Subp_Id)) and then No (Overridden_Operation (Subp_Id)) then Alias_Id := Alias (Subp_Id); if Requires_Overriding (Alias_Id) then return True; elsif Nkind (Parent (Alias_Id)) = N_Procedure_Specification and then Null_Present (Parent (Alias_Id)) then return True; end if; end if; return False; end Is_Non_Overridden_Or_Null_Procedure; -- Local variables Prim_Ops : constant Elist_Id := Direct_Primitive_Operations (Typ); Prim : Entity_Id; Prim_Elmt : Elmt_Id; -- Start of processing for Hide_Non_Overridden_Subprograms begin -- Inspect the list of primitives looking for non-overridden -- subprograms. if Present (Prim_Ops) then Prim_Elmt := First_Elmt (Prim_Ops); while Present (Prim_Elmt) loop Prim := Node (Prim_Elmt); Next_Elmt (Prim_Elmt); if Is_Non_Overridden_Or_Null_Procedure (Prim) then Hide_Matching_Homographs (Subp_Id => Prim, Start_Elmt => Prim_Elmt); end if; end loop; end if; end Hide_Non_Overridden_Subprograms; -- Local variables E : constant Entity_Id := Entity (N); Non_Generic_Case : constant Boolean := Nkind (N) = N_Freeze_Entity; -- True in non-generic case. Some of the processing here is skipped -- for the generic case since it is not needed. Basically in the -- generic case, we only need to do stuff that might generate error -- messages or warnings. -- Start of processing for Freeze_Entity_Checks begin -- Remember that we are processing a freezing entity. Required to -- ensure correct decoration of internal entities associated with -- interfaces (see New_Overloaded_Entity). Inside_Freezing_Actions := Inside_Freezing_Actions + 1; -- For tagged types covering interfaces add internal entities that link -- the primitives of the interfaces with the primitives that cover them. -- Note: These entities were originally generated only when generating -- code because their main purpose was to provide support to initialize -- the secondary dispatch tables. They are now generated also when -- compiling with no code generation to provide ASIS the relationship -- between interface primitives and tagged type primitives. They are -- also used to locate primitives covering interfaces when processing -- generics (see Derive_Subprograms). -- This is not needed in the generic case if Ada_Version >= Ada_2005 and then Non_Generic_Case and then Ekind (E) = E_Record_Type and then Is_Tagged_Type (E) and then not Is_Interface (E) and then Has_Interfaces (E) then -- This would be a good common place to call the routine that checks -- overriding of interface primitives (and thus factorize calls to -- Check_Abstract_Overriding located at different contexts in the -- compiler). However, this is not possible because it causes -- spurious errors in case of late overriding. Add_Internal_Interface_Entities (E); end if; -- After all forms of overriding have been resolved, a tagged type may -- be left with a set of implicitly declared and possibly erroneous -- abstract subprograms, null procedures and subprograms that require -- overriding. If this set contains fully conformant homographs, then -- one is chosen arbitrarily (already done during resolution), otherwise -- all remaining non-fully conformant homographs are hidden from -- visibility (Ada RM 8.3 12.3/2). if Is_Tagged_Type (E) then Hide_Non_Overridden_Subprograms (E); end if; -- Check CPP types if Ekind (E) = E_Record_Type and then Is_CPP_Class (E) and then Is_Tagged_Type (E) and then Tagged_Type_Expansion then if CPP_Num_Prims (E) = 0 then -- If the CPP type has user defined components then it must import -- primitives from C++. This is required because if the C++ class -- has no primitives then the C++ compiler does not added the _tag -- component to the type. if First_Entity (E) /= Last_Entity (E) then Error_Msg_N ("'C'P'P type must import at least one primitive from C++??", E); end if; end if; -- Check that all its primitives are abstract or imported from C++. -- Check also availability of the C++ constructor. declare Has_Constructors : constant Boolean := Has_CPP_Constructors (E); Elmt : Elmt_Id; Error_Reported : Boolean := False; Prim : Node_Id; begin Elmt := First_Elmt (Primitive_Operations (E)); while Present (Elmt) loop Prim := Node (Elmt); if Comes_From_Source (Prim) then if Is_Abstract_Subprogram (Prim) then null; elsif not Is_Imported (Prim) or else Convention (Prim) /= Convention_CPP then Error_Msg_N ("primitives of 'C'P'P types must be imported from C++ " & "or abstract??", Prim); elsif not Has_Constructors and then not Error_Reported then Error_Msg_Name_1 := Chars (E); Error_Msg_N ("??'C'P'P constructor required for type %", Prim); Error_Reported := True; end if; end if; Next_Elmt (Elmt); end loop; end; end if; -- Check Ada derivation of CPP type if Expander_Active -- why? losing errors in -gnatc mode??? and then Present (Etype (E)) -- defend against errors and then Tagged_Type_Expansion and then Ekind (E) = E_Record_Type and then Etype (E) /= E and then Is_CPP_Class (Etype (E)) and then CPP_Num_Prims (Etype (E)) > 0 and then not Is_CPP_Class (E) and then not Has_CPP_Constructors (Etype (E)) then -- If the parent has C++ primitives but it has no constructor then -- check that all the primitives are overridden in this derivation; -- otherwise the constructor of the parent is needed to build the -- dispatch table. declare Elmt : Elmt_Id; Prim : Node_Id; begin Elmt := First_Elmt (Primitive_Operations (E)); while Present (Elmt) loop Prim := Node (Elmt); if not Is_Abstract_Subprogram (Prim) and then No (Interface_Alias (Prim)) and then Find_Dispatching_Type (Ultimate_Alias (Prim)) /= E then Error_Msg_Name_1 := Chars (Etype (E)); Error_Msg_N ("'C'P'P constructor required for parent type %", E); exit; end if; Next_Elmt (Elmt); end loop; end; end if; Inside_Freezing_Actions := Inside_Freezing_Actions - 1; -- If we have a type with predicates, build predicate function. This is -- not needed in the generic case, nor within TSS subprograms and other -- predefined primitives. if Is_Type (E) and then Non_Generic_Case and then not Within_Internal_Subprogram and then Has_Predicates (E) then Build_Predicate_Functions (E, N); end if; -- If type has delayed aspects, this is where we do the preanalysis at -- the freeze point, as part of the consistent visibility check. Note -- that this must be done after calling Build_Predicate_Functions or -- Build_Invariant_Procedure since these subprograms fix occurrences of -- the subtype name in the saved expression so that they will not cause -- trouble in the preanalysis. -- This is also not needed in the generic case if Non_Generic_Case and then Has_Delayed_Aspects (E) and then Scope (E) = Current_Scope then -- Retrieve the visibility to the discriminants in order to properly -- analyze the aspects. Push_Scope_And_Install_Discriminants (E); declare Ritem : Node_Id; begin -- Look for aspect specification entries for this entity Ritem := First_Rep_Item (E); while Present (Ritem) loop if Nkind (Ritem) = N_Aspect_Specification and then Entity (Ritem) = E and then Is_Delayed_Aspect (Ritem) then Check_Aspect_At_Freeze_Point (Ritem); end if; Next_Rep_Item (Ritem); end loop; end; Uninstall_Discriminants_And_Pop_Scope (E); end if; -- For a record type, deal with variant parts. This has to be delayed -- to this point, because of the issue of statically predicated -- subtypes, which we have to ensure are frozen before checking -- choices, since we need to have the static choice list set. if Is_Record_Type (E) then Check_Variant_Part : declare D : constant Node_Id := Declaration_Node (E); T : Node_Id; C : Node_Id; VP : Node_Id; Others_Present : Boolean; pragma Warnings (Off, Others_Present); -- Indicates others present, not used in this case procedure Non_Static_Choice_Error (Choice : Node_Id); -- Error routine invoked by the generic instantiation below when -- the variant part has a non static choice. procedure Process_Declarations (Variant : Node_Id); -- Processes declarations associated with a variant. We analyzed -- the declarations earlier (in Sem_Ch3.Analyze_Variant_Part), -- but we still need the recursive call to Check_Choices for any -- nested variant to get its choices properly processed. This is -- also where we expand out the choices if expansion is active. package Variant_Choices_Processing is new Generic_Check_Choices (Process_Empty_Choice => No_OP, Process_Non_Static_Choice => Non_Static_Choice_Error, Process_Associated_Node => Process_Declarations); use Variant_Choices_Processing; ----------------------------- -- Non_Static_Choice_Error -- ----------------------------- procedure Non_Static_Choice_Error (Choice : Node_Id) is begin Flag_Non_Static_Expr ("choice given in variant part is not static!", Choice); end Non_Static_Choice_Error; -------------------------- -- Process_Declarations -- -------------------------- procedure Process_Declarations (Variant : Node_Id) is CL : constant Node_Id := Component_List (Variant); VP : Node_Id; begin -- Check for static predicate present in this variant if Has_SP_Choice (Variant) then -- Here we expand. You might expect to find this call in -- Expand_N_Variant_Part, but that is called when we first -- see the variant part, and we cannot do this expansion -- earlier than the freeze point, since for statically -- predicated subtypes, the predicate is not known till -- the freeze point. -- Furthermore, we do this expansion even if the expander -- is not active, because other semantic processing, e.g. -- for aggregates, requires the expanded list of choices. -- If the expander is not active, then we can't just clobber -- the list since it would invalidate the ASIS -gnatct tree. -- So we have to rewrite the variant part with a Rewrite -- call that replaces it with a copy and clobber the copy. if not Expander_Active then declare NewV : constant Node_Id := New_Copy (Variant); begin Set_Discrete_Choices (NewV, New_Copy_List (Discrete_Choices (Variant))); Rewrite (Variant, NewV); end; end if; Expand_Static_Predicates_In_Choices (Variant); end if; -- We don't need to worry about the declarations in the variant -- (since they were analyzed by Analyze_Choices when we first -- encountered the variant), but we do need to take care of -- expansion of any nested variants. if not Null_Present (CL) then VP := Variant_Part (CL); if Present (VP) then Check_Choices (VP, Variants (VP), Etype (Name (VP)), Others_Present); end if; end if; end Process_Declarations; -- Start of processing for Check_Variant_Part begin -- Find component list C := Empty; if Nkind (D) = N_Full_Type_Declaration then T := Type_Definition (D); if Nkind (T) = N_Record_Definition then C := Component_List (T); elsif Nkind (T) = N_Derived_Type_Definition and then Present (Record_Extension_Part (T)) then C := Component_List (Record_Extension_Part (T)); end if; end if; -- Case of variant part present if Present (C) and then Present (Variant_Part (C)) then VP := Variant_Part (C); -- Check choices Check_Choices (VP, Variants (VP), Etype (Name (VP)), Others_Present); -- If the last variant does not contain the Others choice, -- replace it with an N_Others_Choice node since Gigi always -- wants an Others. Note that we do not bother to call Analyze -- on the modified variant part, since its only effect would be -- to compute the Others_Discrete_Choices node laboriously, and -- of course we already know the list of choices corresponding -- to the others choice (it's the list we're replacing). -- We only want to do this if the expander is active, since -- we do not want to clobber the ASIS tree. if Expander_Active then declare Last_Var : constant Node_Id := Last_Non_Pragma (Variants (VP)); Others_Node : Node_Id; begin if Nkind (First (Discrete_Choices (Last_Var))) /= N_Others_Choice then Others_Node := Make_Others_Choice (Sloc (Last_Var)); Set_Others_Discrete_Choices (Others_Node, Discrete_Choices (Last_Var)); Set_Discrete_Choices (Last_Var, New_List (Others_Node)); end if; end; end if; end if; end Check_Variant_Part; end if; end Freeze_Entity_Checks; ------------------------- -- Get_Alignment_Value -- ------------------------- function Get_Alignment_Value (Expr : Node_Id) return Uint is Align : constant Uint := Static_Integer (Expr); begin if Align = No_Uint then return No_Uint; elsif Align <= 0 then -- This error is suppressed in ASIS mode to allow for different ASIS -- back ends or ASIS-based tools to query the illegal clause. if not ASIS_Mode then Error_Msg_N ("alignment value must be positive", Expr); end if; return No_Uint; else for J in Int range 0 .. 64 loop declare M : constant Uint := Uint_2 ** J; begin exit when M = Align; if M > Align then -- This error is suppressed in ASIS mode to allow for -- different ASIS back ends or ASIS-based tools to query the -- illegal clause. if not ASIS_Mode then Error_Msg_N ("alignment value must be power of 2", Expr); end if; return No_Uint; end if; end; end loop; return Align; end if; end Get_Alignment_Value; ----------------------------- -- Get_Interfacing_Aspects -- ----------------------------- procedure Get_Interfacing_Aspects (Iface_Asp : Node_Id; Conv_Asp : out Node_Id; EN_Asp : out Node_Id; Expo_Asp : out Node_Id; Imp_Asp : out Node_Id; LN_Asp : out Node_Id; Do_Checks : Boolean := False) is procedure Save_Or_Duplication_Error (Asp : Node_Id; To : in out Node_Id); -- Save the value of aspect Asp in node To. If To already has a value, -- then this is considered a duplicate use of aspect. Emit an error if -- flag Do_Checks is set. ------------------------------- -- Save_Or_Duplication_Error -- ------------------------------- procedure Save_Or_Duplication_Error (Asp : Node_Id; To : in out Node_Id) is begin -- Detect an extra aspect and issue an error if Present (To) then if Do_Checks then Error_Msg_Name_1 := Chars (Identifier (Asp)); Error_Msg_Sloc := Sloc (To); Error_Msg_N ("aspect % previously given #", Asp); end if; -- Otherwise capture the aspect else To := Asp; end if; end Save_Or_Duplication_Error; -- Local variables Asp : Node_Id; Asp_Id : Aspect_Id; -- The following variables capture each individual aspect Conv : Node_Id := Empty; EN : Node_Id := Empty; Expo : Node_Id := Empty; Imp : Node_Id := Empty; LN : Node_Id := Empty; -- Start of processing for Get_Interfacing_Aspects begin -- The input interfacing aspect should reside in an aspect specification -- list. pragma Assert (Is_List_Member (Iface_Asp)); -- Examine the aspect specifications of the related entity. Find and -- capture all interfacing aspects. Detect duplicates and emit errors -- if applicable. Asp := First (List_Containing (Iface_Asp)); while Present (Asp) loop Asp_Id := Get_Aspect_Id (Asp); if Asp_Id = Aspect_Convention then Save_Or_Duplication_Error (Asp, Conv); elsif Asp_Id = Aspect_External_Name then Save_Or_Duplication_Error (Asp, EN); elsif Asp_Id = Aspect_Export then Save_Or_Duplication_Error (Asp, Expo); elsif Asp_Id = Aspect_Import then Save_Or_Duplication_Error (Asp, Imp); elsif Asp_Id = Aspect_Link_Name then Save_Or_Duplication_Error (Asp, LN); end if; Next (Asp); end loop; Conv_Asp := Conv; EN_Asp := EN; Expo_Asp := Expo; Imp_Asp := Imp; LN_Asp := LN; end Get_Interfacing_Aspects; ------------------------------------- -- Inherit_Aspects_At_Freeze_Point -- ------------------------------------- procedure Inherit_Aspects_At_Freeze_Point (Typ : Entity_Id) is function Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item (Rep_Item : Node_Id) return Boolean; -- This routine checks if Rep_Item is either a pragma or an aspect -- specification node whose correponding pragma (if any) is present in -- the Rep Item chain of the entity it has been specified to. -------------------------------------------------- -- Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item -- -------------------------------------------------- function Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item (Rep_Item : Node_Id) return Boolean is begin return Nkind (Rep_Item) = N_Pragma or else Present_In_Rep_Item (Entity (Rep_Item), Aspect_Rep_Item (Rep_Item)); end Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item; -- Start of processing for Inherit_Aspects_At_Freeze_Point begin -- A representation item is either subtype-specific (Size and Alignment -- clauses) or type-related (all others). Subtype-specific aspects may -- differ for different subtypes of the same type (RM 13.1.8). -- A derived type inherits each type-related representation aspect of -- its parent type that was directly specified before the declaration of -- the derived type (RM 13.1.15). -- A derived subtype inherits each subtype-specific representation -- aspect of its parent subtype that was directly specified before the -- declaration of the derived type (RM 13.1.15). -- The general processing involves inheriting a representation aspect -- from a parent type whenever the first rep item (aspect specification, -- attribute definition clause, pragma) corresponding to the given -- representation aspect in the rep item chain of Typ, if any, isn't -- directly specified to Typ but to one of its parents. -- ??? Note that, for now, just a limited number of representation -- aspects have been inherited here so far. Many of them are -- still inherited in Sem_Ch3. This will be fixed soon. Here is -- a non- exhaustive list of aspects that likely also need to -- be moved to this routine: Alignment, Component_Alignment, -- Component_Size, Machine_Radix, Object_Size, Pack, Predicates, -- Preelaborable_Initialization, RM_Size and Small. -- In addition, Convention must be propagated from base type to subtype, -- because the subtype may have been declared on an incomplete view. if Nkind (Parent (Typ)) = N_Private_Extension_Declaration then return; end if; -- Ada_05/Ada_2005 if not Has_Rep_Item (Typ, Name_Ada_05, Name_Ada_2005, False) and then Has_Rep_Item (Typ, Name_Ada_05, Name_Ada_2005) and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item (Get_Rep_Item (Typ, Name_Ada_05, Name_Ada_2005)) then Set_Is_Ada_2005_Only (Typ); end if; -- Ada_12/Ada_2012 if not Has_Rep_Item (Typ, Name_Ada_12, Name_Ada_2012, False) and then Has_Rep_Item (Typ, Name_Ada_12, Name_Ada_2012) and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item (Get_Rep_Item (Typ, Name_Ada_12, Name_Ada_2012)) then Set_Is_Ada_2012_Only (Typ); end if; -- Atomic/Shared if not Has_Rep_Item (Typ, Name_Atomic, Name_Shared, False) and then Has_Rep_Pragma (Typ, Name_Atomic, Name_Shared) and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item (Get_Rep_Item (Typ, Name_Atomic, Name_Shared)) then Set_Is_Atomic (Typ); Set_Is_Volatile (Typ); Set_Treat_As_Volatile (Typ); end if; -- Convention if Is_Record_Type (Typ) and then Typ /= Base_Type (Typ) and then Is_Frozen (Base_Type (Typ)) then Set_Convention (Typ, Convention (Base_Type (Typ))); end if; -- Default_Component_Value -- Verify that there is no rep_item declared for the type, and there -- is one coming from an ancestor. if Is_Array_Type (Typ) and then Is_Base_Type (Typ) and then not Has_Rep_Item (Typ, Name_Default_Component_Value, False) and then Has_Rep_Item (Typ, Name_Default_Component_Value) then Set_Default_Aspect_Component_Value (Typ, Default_Aspect_Component_Value (Entity (Get_Rep_Item (Typ, Name_Default_Component_Value)))); end if; -- Default_Value if Is_Scalar_Type (Typ) and then Is_Base_Type (Typ) and then not Has_Rep_Item (Typ, Name_Default_Value, False) and then Has_Rep_Item (Typ, Name_Default_Value) then Set_Has_Default_Aspect (Typ); Set_Default_Aspect_Value (Typ, Default_Aspect_Value (Entity (Get_Rep_Item (Typ, Name_Default_Value)))); end if; -- Discard_Names if not Has_Rep_Item (Typ, Name_Discard_Names, False) and then Has_Rep_Item (Typ, Name_Discard_Names) and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item (Get_Rep_Item (Typ, Name_Discard_Names)) then Set_Discard_Names (Typ); end if; -- Volatile if not Has_Rep_Item (Typ, Name_Volatile, False) and then Has_Rep_Item (Typ, Name_Volatile) and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item (Get_Rep_Item (Typ, Name_Volatile)) then Set_Is_Volatile (Typ); Set_Treat_As_Volatile (Typ); end if; -- Volatile_Full_Access if not Has_Rep_Item (Typ, Name_Volatile_Full_Access, False) and then Has_Rep_Pragma (Typ, Name_Volatile_Full_Access) and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item (Get_Rep_Item (Typ, Name_Volatile_Full_Access)) then Set_Is_Volatile_Full_Access (Typ); Set_Is_Volatile (Typ); Set_Treat_As_Volatile (Typ); end if; -- Inheritance for derived types only if Is_Derived_Type (Typ) then declare Bas_Typ : constant Entity_Id := Base_Type (Typ); Imp_Bas_Typ : constant Entity_Id := Implementation_Base_Type (Typ); begin -- Atomic_Components if not Has_Rep_Item (Typ, Name_Atomic_Components, False) and then Has_Rep_Item (Typ, Name_Atomic_Components) and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item (Get_Rep_Item (Typ, Name_Atomic_Components)) then Set_Has_Atomic_Components (Imp_Bas_Typ); end if; -- Volatile_Components if not Has_Rep_Item (Typ, Name_Volatile_Components, False) and then Has_Rep_Item (Typ, Name_Volatile_Components) and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item (Get_Rep_Item (Typ, Name_Volatile_Components)) then Set_Has_Volatile_Components (Imp_Bas_Typ); end if; -- Finalize_Storage_Only if not Has_Rep_Pragma (Typ, Name_Finalize_Storage_Only, False) and then Has_Rep_Pragma (Typ, Name_Finalize_Storage_Only) then Set_Finalize_Storage_Only (Bas_Typ); end if; -- Universal_Aliasing if not Has_Rep_Item (Typ, Name_Universal_Aliasing, False) and then Has_Rep_Item (Typ, Name_Universal_Aliasing) and then Is_Pragma_Or_Corr_Pragma_Present_In_Rep_Item (Get_Rep_Item (Typ, Name_Universal_Aliasing)) then Set_Universal_Aliasing (Imp_Bas_Typ); end if; -- Bit_Order if Is_Record_Type (Typ) then if not Has_Rep_Item (Typ, Name_Bit_Order, False) and then Has_Rep_Item (Typ, Name_Bit_Order) then Set_Reverse_Bit_Order (Bas_Typ, Reverse_Bit_Order (Entity (Name (Get_Rep_Item (Typ, Name_Bit_Order))))); end if; end if; -- Scalar_Storage_Order -- Note: the aspect is specified on a first subtype, but recorded -- in a flag of the base type! if (Is_Record_Type (Typ) or else Is_Array_Type (Typ)) and then Typ = Bas_Typ then -- For a type extension, always inherit from parent; otherwise -- inherit if no default applies. Note: we do not check for -- an explicit rep item on the parent type when inheriting, -- because the parent SSO may itself have been set by default. if not Has_Rep_Item (First_Subtype (Typ), Name_Scalar_Storage_Order, False) and then (Is_Tagged_Type (Bas_Typ) or else not (SSO_Set_Low_By_Default (Bas_Typ) or else SSO_Set_High_By_Default (Bas_Typ))) then Set_Reverse_Storage_Order (Bas_Typ, Reverse_Storage_Order (Implementation_Base_Type (Etype (Bas_Typ)))); -- Clear default SSO indications, since the inherited aspect -- which was set explicitly overrides the default. Set_SSO_Set_Low_By_Default (Bas_Typ, False); Set_SSO_Set_High_By_Default (Bas_Typ, False); end if; end if; end; end if; end Inherit_Aspects_At_Freeze_Point; ---------------- -- Initialize -- ---------------- procedure Initialize is begin Address_Clause_Checks.Init; Unchecked_Conversions.Init; if AAMP_On_Target then Independence_Checks.Init; end if; end Initialize; --------------------------- -- Install_Discriminants -- --------------------------- procedure Install_Discriminants (E : Entity_Id) is Disc : Entity_Id; Prev : Entity_Id; begin Disc := First_Discriminant (E); while Present (Disc) loop Prev := Current_Entity (Disc); Set_Current_Entity (Disc); Set_Is_Immediately_Visible (Disc); Set_Homonym (Disc, Prev); Next_Discriminant (Disc); end loop; end Install_Discriminants; ------------------------- -- Is_Operational_Item -- ------------------------- function Is_Operational_Item (N : Node_Id) return Boolean is begin if Nkind (N) /= N_Attribute_Definition_Clause then return False; else declare Id : constant Attribute_Id := Get_Attribute_Id (Chars (N)); begin -- List of operational items is given in AARM 13.1(8.mm/1). -- It is clearly incomplete, as it does not include iterator -- aspects, among others. return Id = Attribute_Constant_Indexing or else Id = Attribute_Default_Iterator or else Id = Attribute_Implicit_Dereference or else Id = Attribute_Input or else Id = Attribute_Iterator_Element or else Id = Attribute_Iterable or else Id = Attribute_Output or else Id = Attribute_Read or else Id = Attribute_Variable_Indexing or else Id = Attribute_Write or else Id = Attribute_External_Tag; end; end if; end Is_Operational_Item; ------------------------- -- Is_Predicate_Static -- ------------------------- -- Note: the basic legality of the expression has already been checked, so -- we don't need to worry about cases or ranges on strings for example. function Is_Predicate_Static (Expr : Node_Id; Nam : Name_Id) return Boolean is function All_Static_Case_Alternatives (L : List_Id) return Boolean; -- Given a list of case expression alternatives, returns True if all -- the alternatives are static (have all static choices, and a static -- expression). function All_Static_Choices (L : List_Id) return Boolean; -- Returns true if all elements of the list are OK static choices -- as defined below for Is_Static_Choice. Used for case expression -- alternatives and for the right operand of a membership test. An -- others_choice is static if the corresponding expression is static. -- The staticness of the bounds is checked separately. function Is_Static_Choice (N : Node_Id) return Boolean; -- Returns True if N represents a static choice (static subtype, or -- static subtype indication, or static expression, or static range). -- -- Note that this is a bit more inclusive than we actually need -- (in particular membership tests do not allow the use of subtype -- indications). But that doesn't matter, we have already checked -- that the construct is legal to get this far. function Is_Type_Ref (N : Node_Id) return Boolean; pragma Inline (Is_Type_Ref); -- Returns True if N is a reference to the type for the predicate in the -- expression (i.e. if it is an identifier whose Chars field matches the -- Nam given in the call). N must not be parenthesized, if the type name -- appears in parens, this routine will return False. ---------------------------------- -- All_Static_Case_Alternatives -- ---------------------------------- function All_Static_Case_Alternatives (L : List_Id) return Boolean is N : Node_Id; begin N := First (L); while Present (N) loop if not (All_Static_Choices (Discrete_Choices (N)) and then Is_OK_Static_Expression (Expression (N))) then return False; end if; Next (N); end loop; return True; end All_Static_Case_Alternatives; ------------------------ -- All_Static_Choices -- ------------------------ function All_Static_Choices (L : List_Id) return Boolean is N : Node_Id; begin N := First (L); while Present (N) loop if not Is_Static_Choice (N) then return False; end if; Next (N); end loop; return True; end All_Static_Choices; ---------------------- -- Is_Static_Choice -- ---------------------- function Is_Static_Choice (N : Node_Id) return Boolean is begin return Nkind (N) = N_Others_Choice or else Is_OK_Static_Expression (N) or else (Is_Entity_Name (N) and then Is_Type (Entity (N)) and then Is_OK_Static_Subtype (Entity (N))) or else (Nkind (N) = N_Subtype_Indication and then Is_OK_Static_Subtype (Entity (N))) or else (Nkind (N) = N_Range and then Is_OK_Static_Range (N)); end Is_Static_Choice; ----------------- -- Is_Type_Ref -- ----------------- function Is_Type_Ref (N : Node_Id) return Boolean is begin return Nkind (N) = N_Identifier and then Chars (N) = Nam and then Paren_Count (N) = 0; end Is_Type_Ref; -- Start of processing for Is_Predicate_Static begin -- Predicate_Static means one of the following holds. Numbers are the -- corresponding paragraph numbers in (RM 3.2.4(16-22)). -- 16: A static expression if Is_OK_Static_Expression (Expr) then return True; -- 17: A membership test whose simple_expression is the current -- instance, and whose membership_choice_list meets the requirements -- for a static membership test. elsif Nkind (Expr) in N_Membership_Test and then ((Present (Right_Opnd (Expr)) and then Is_Static_Choice (Right_Opnd (Expr))) or else (Present (Alternatives (Expr)) and then All_Static_Choices (Alternatives (Expr)))) then return True; -- 18. A case_expression whose selecting_expression is the current -- instance, and whose dependent expressions are static expressions. elsif Nkind (Expr) = N_Case_Expression and then Is_Type_Ref (Expression (Expr)) and then All_Static_Case_Alternatives (Alternatives (Expr)) then return True; -- 19. A call to a predefined equality or ordering operator, where one -- operand is the current instance, and the other is a static -- expression. -- Note: the RM is clearly wrong here in not excluding string types. -- Without this exclusion, we would allow expressions like X > "ABC" -- to be considered as predicate-static, which is clearly not intended, -- since the idea is for predicate-static to be a subset of normal -- static expressions (and "DEF" > "ABC" is not a static expression). -- However, we do allow internally generated (not from source) equality -- and inequality operations to be valid on strings (this helps deal -- with cases where we transform A in "ABC" to A = "ABC). elsif Nkind (Expr) in N_Op_Compare and then ((not Is_String_Type (Etype (Left_Opnd (Expr)))) or else (Nkind_In (Expr, N_Op_Eq, N_Op_Ne) and then not Comes_From_Source (Expr))) and then ((Is_Type_Ref (Left_Opnd (Expr)) and then Is_OK_Static_Expression (Right_Opnd (Expr))) or else (Is_Type_Ref (Right_Opnd (Expr)) and then Is_OK_Static_Expression (Left_Opnd (Expr)))) then return True; -- 20. A call to a predefined boolean logical operator, where each -- operand is predicate-static. elsif (Nkind_In (Expr, N_Op_And, N_Op_Or, N_Op_Xor) and then Is_Predicate_Static (Left_Opnd (Expr), Nam) and then Is_Predicate_Static (Right_Opnd (Expr), Nam)) or else (Nkind (Expr) = N_Op_Not and then Is_Predicate_Static (Right_Opnd (Expr), Nam)) then return True; -- 21. A short-circuit control form where both operands are -- predicate-static. elsif Nkind (Expr) in N_Short_Circuit and then Is_Predicate_Static (Left_Opnd (Expr), Nam) and then Is_Predicate_Static (Right_Opnd (Expr), Nam) then return True; -- 22. A parenthesized predicate-static expression. This does not -- require any special test, since we just ignore paren levels in -- all the cases above. -- One more test that is an implementation artifact caused by the fact -- that we are analyzing not the original expression, but the generated -- expression in the body of the predicate function. This can include -- references to inherited predicates, so that the expression we are -- processing looks like: -- xxPredicate (typ (Inns)) and then expression -- Where the call is to a Predicate function for an inherited predicate. -- We simply ignore such a call, which could be to either a dynamic or -- a static predicate. Note that if the parent predicate is dynamic then -- eventually this type will be marked as dynamic, but you are allowed -- to specify a static predicate for a subtype which is inheriting a -- dynamic predicate, so the static predicate validation here ignores -- the inherited predicate even if it is dynamic. -- In all cases, a static predicate can only apply to a scalar type. elsif Nkind (Expr) = N_Function_Call and then Is_Predicate_Function (Entity (Name (Expr))) and then Is_Scalar_Type (Etype (First_Entity (Entity (Name (Expr))))) then return True; -- That's an exhaustive list of tests, all other cases are not -- predicate-static, so we return False. else return False; end if; end Is_Predicate_Static; --------------------- -- Kill_Rep_Clause -- --------------------- procedure Kill_Rep_Clause (N : Node_Id) is begin pragma Assert (Ignore_Rep_Clauses); -- Note: we use Replace rather than Rewrite, because we don't want -- ASIS to be able to use Original_Node to dig out the (undecorated) -- rep clause that is being replaced. Replace (N, Make_Null_Statement (Sloc (N))); -- The null statement must be marked as not coming from source. This is -- so that ASIS ignores it, and also the back end does not expect bogus -- "from source" null statements in weird places (e.g. in declarative -- regions where such null statements are not allowed). Set_Comes_From_Source (N, False); end Kill_Rep_Clause; ------------------ -- Minimum_Size -- ------------------ function Minimum_Size (T : Entity_Id; Biased : Boolean := False) return Nat is Lo : Uint := No_Uint; Hi : Uint := No_Uint; LoR : Ureal := No_Ureal; HiR : Ureal := No_Ureal; LoSet : Boolean := False; HiSet : Boolean := False; B : Uint; S : Nat; Ancest : Entity_Id; R_Typ : constant Entity_Id := Root_Type (T); begin -- If bad type, return 0 if T = Any_Type then return 0; -- For generic types, just return zero. There cannot be any legitimate -- need to know such a size, but this routine may be called with a -- generic type as part of normal processing. elsif Is_Generic_Type (R_Typ) or else R_Typ = Any_Type then return 0; -- Access types (cannot have size smaller than System.Address) elsif Is_Access_Type (T) then return System_Address_Size; -- Floating-point types elsif Is_Floating_Point_Type (T) then return UI_To_Int (Esize (R_Typ)); -- Discrete types elsif Is_Discrete_Type (T) then -- The following loop is looking for the nearest compile time known -- bounds following the ancestor subtype chain. The idea is to find -- the most restrictive known bounds information. Ancest := T; loop if Ancest = Any_Type or else Etype (Ancest) = Any_Type then return 0; end if; if not LoSet then if Compile_Time_Known_Value (Type_Low_Bound (Ancest)) then Lo := Expr_Rep_Value (Type_Low_Bound (Ancest)); LoSet := True; exit when HiSet; end if; end if; if not HiSet then if Compile_Time_Known_Value (Type_High_Bound (Ancest)) then Hi := Expr_Rep_Value (Type_High_Bound (Ancest)); HiSet := True; exit when LoSet; end if; end if; Ancest := Ancestor_Subtype (Ancest); if No (Ancest) then Ancest := Base_Type (T); if Is_Generic_Type (Ancest) then return 0; end if; end if; end loop; -- Fixed-point types. We can't simply use Expr_Value to get the -- Corresponding_Integer_Value values of the bounds, since these do not -- get set till the type is frozen, and this routine can be called -- before the type is frozen. Similarly the test for bounds being static -- needs to include the case where we have unanalyzed real literals for -- the same reason. elsif Is_Fixed_Point_Type (T) then -- The following loop is looking for the nearest compile time known -- bounds following the ancestor subtype chain. The idea is to find -- the most restrictive known bounds information. Ancest := T; loop if Ancest = Any_Type or else Etype (Ancest) = Any_Type then return 0; end if; -- Note: In the following two tests for LoSet and HiSet, it may -- seem redundant to test for N_Real_Literal here since normally -- one would assume that the test for the value being known at -- compile time includes this case. However, there is a glitch. -- If the real literal comes from folding a non-static expression, -- then we don't consider any non- static expression to be known -- at compile time if we are in configurable run time mode (needed -- in some cases to give a clearer definition of what is and what -- is not accepted). So the test is indeed needed. Without it, we -- would set neither Lo_Set nor Hi_Set and get an infinite loop. if not LoSet then if Nkind (Type_Low_Bound (Ancest)) = N_Real_Literal or else Compile_Time_Known_Value (Type_Low_Bound (Ancest)) then LoR := Expr_Value_R (Type_Low_Bound (Ancest)); LoSet := True; exit when HiSet; end if; end if; if not HiSet then if Nkind (Type_High_Bound (Ancest)) = N_Real_Literal or else Compile_Time_Known_Value (Type_High_Bound (Ancest)) then HiR := Expr_Value_R (Type_High_Bound (Ancest)); HiSet := True; exit when LoSet; end if; end if; Ancest := Ancestor_Subtype (Ancest); if No (Ancest) then Ancest := Base_Type (T); if Is_Generic_Type (Ancest) then return 0; end if; end if; end loop; Lo := UR_To_Uint (LoR / Small_Value (T)); Hi := UR_To_Uint (HiR / Small_Value (T)); -- No other types allowed else raise Program_Error; end if; -- Fall through with Hi and Lo set. Deal with biased case if (Biased and then not Is_Fixed_Point_Type (T) and then not (Is_Enumeration_Type (T) and then Has_Non_Standard_Rep (T))) or else Has_Biased_Representation (T) then Hi := Hi - Lo; Lo := Uint_0; end if; -- Null range case, size is always zero. We only do this in the discrete -- type case, since that's the odd case that came up. Probably we should -- also do this in the fixed-point case, but doing so causes peculiar -- gigi failures, and it is not worth worrying about this incredibly -- marginal case (explicit null-range fixed-point type declarations)??? if Lo > Hi and then Is_Discrete_Type (T) then S := 0; -- Signed case. Note that we consider types like range 1 .. -1 to be -- signed for the purpose of computing the size, since the bounds have -- to be accommodated in the base type. elsif Lo < 0 or else Hi < 0 then S := 1; B := Uint_1; -- S = size, B = 2 ** (size - 1) (can accommodate -B .. +(B - 1)) -- Note that we accommodate the case where the bounds cross. This -- can happen either because of the way the bounds are declared -- or because of the algorithm in Freeze_Fixed_Point_Type. while Lo < -B or else Hi < -B or else Lo >= B or else Hi >= B loop B := Uint_2 ** S; S := S + 1; end loop; -- Unsigned case else -- If both bounds are positive, make sure that both are represen- -- table in the case where the bounds are crossed. This can happen -- either because of the way the bounds are declared, or because of -- the algorithm in Freeze_Fixed_Point_Type. if Lo > Hi then Hi := Lo; end if; -- S = size, (can accommodate 0 .. (2**size - 1)) S := 0; while Hi >= Uint_2 ** S loop S := S + 1; end loop; end if; return S; end Minimum_Size; --------------------------- -- New_Stream_Subprogram -- --------------------------- procedure New_Stream_Subprogram (N : Node_Id; Ent : Entity_Id; Subp : Entity_Id; Nam : TSS_Name_Type) is Loc : constant Source_Ptr := Sloc (N); Sname : constant Name_Id := Make_TSS_Name (Base_Type (Ent), Nam); Subp_Id : Entity_Id; Subp_Decl : Node_Id; F : Entity_Id; Etyp : Entity_Id; Defer_Declaration : constant Boolean := Is_Tagged_Type (Ent) or else Is_Private_Type (Ent); -- For a tagged type, there is a declaration for each stream attribute -- at the freeze point, and we must generate only a completion of this -- declaration. We do the same for private types, because the full view -- might be tagged. Otherwise we generate a declaration at the point of -- the attribute definition clause. If the attribute definition comes -- from an aspect specification the declaration is part of the freeze -- actions of the type. function Build_Spec return Node_Id; -- Used for declaration and renaming declaration, so that this is -- treated as a renaming_as_body. ---------------- -- Build_Spec -- ---------------- function Build_Spec return Node_Id is Out_P : constant Boolean := (Nam = TSS_Stream_Read); Formals : List_Id; Spec : Node_Id; T_Ref : constant Node_Id := New_Occurrence_Of (Etyp, Loc); begin Subp_Id := Make_Defining_Identifier (Loc, Sname); -- S : access Root_Stream_Type'Class Formals := New_List ( Make_Parameter_Specification (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_S), Parameter_Type => Make_Access_Definition (Loc, Subtype_Mark => New_Occurrence_Of ( Designated_Type (Etype (F)), Loc)))); if Nam = TSS_Stream_Input then Spec := Make_Function_Specification (Loc, Defining_Unit_Name => Subp_Id, Parameter_Specifications => Formals, Result_Definition => T_Ref); else -- V : [out] T Append_To (Formals, Make_Parameter_Specification (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_V), Out_Present => Out_P, Parameter_Type => T_Ref)); Spec := Make_Procedure_Specification (Loc, Defining_Unit_Name => Subp_Id, Parameter_Specifications => Formals); end if; return Spec; end Build_Spec; -- Start of processing for New_Stream_Subprogram begin F := First_Formal (Subp); if Ekind (Subp) = E_Procedure then Etyp := Etype (Next_Formal (F)); else Etyp := Etype (Subp); end if; -- Prepare subprogram declaration and insert it as an action on the -- clause node. The visibility for this entity is used to test for -- visibility of the attribute definition clause (in the sense of -- 8.3(23) as amended by AI-195). if not Defer_Declaration then Subp_Decl := Make_Subprogram_Declaration (Loc, Specification => Build_Spec); -- For a tagged type, there is always a visible declaration for each -- stream TSS (it is a predefined primitive operation), and the -- completion of this declaration occurs at the freeze point, which is -- not always visible at places where the attribute definition clause is -- visible. So, we create a dummy entity here for the purpose of -- tracking the visibility of the attribute definition clause itself. else Subp_Id := Make_Defining_Identifier (Loc, New_External_Name (Sname, 'V')); Subp_Decl := Make_Object_Declaration (Loc, Defining_Identifier => Subp_Id, Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc)); end if; if not Defer_Declaration and then From_Aspect_Specification (N) and then Has_Delayed_Freeze (Ent) then Append_Freeze_Action (Ent, Subp_Decl); else Insert_Action (N, Subp_Decl); Set_Entity (N, Subp_Id); end if; Subp_Decl := Make_Subprogram_Renaming_Declaration (Loc, Specification => Build_Spec, Name => New_Occurrence_Of (Subp, Loc)); if Defer_Declaration then Set_TSS (Base_Type (Ent), Subp_Id); else if From_Aspect_Specification (N) then Append_Freeze_Action (Ent, Subp_Decl); else Insert_Action (N, Subp_Decl); end if; Copy_TSS (Subp_Id, Base_Type (Ent)); end if; end New_Stream_Subprogram; ------------------------------------------ -- Push_Scope_And_Install_Discriminants -- ------------------------------------------ procedure Push_Scope_And_Install_Discriminants (E : Entity_Id) is begin if Has_Discriminants (E) then Push_Scope (E); -- Make the discriminants visible for type declarations and protected -- type declarations, not for subtype declarations (RM 13.1.1 (12/3)) if Nkind (Parent (E)) /= N_Subtype_Declaration then Install_Discriminants (E); end if; end if; end Push_Scope_And_Install_Discriminants; ------------------------ -- Rep_Item_Too_Early -- ------------------------ function Rep_Item_Too_Early (T : Entity_Id; N : Node_Id) return Boolean is begin -- Cannot apply non-operational rep items to generic types if Is_Operational_Item (N) then return False; elsif Is_Type (T) and then Is_Generic_Type (Root_Type (T)) and then (Nkind (N) /= N_Pragma or else Get_Pragma_Id (N) /= Pragma_Convention) then Error_Msg_N ("representation item not allowed for generic type", N); return True; end if; -- Otherwise check for incomplete type if Is_Incomplete_Or_Private_Type (T) and then No (Underlying_Type (T)) and then (Nkind (N) /= N_Pragma or else Get_Pragma_Id (N) /= Pragma_Import) then Error_Msg_N ("representation item must be after full type declaration", N); return True; -- If the type has incomplete components, a representation clause is -- illegal but stream attributes and Convention pragmas are correct. elsif Has_Private_Component (T) then if Nkind (N) = N_Pragma then return False; else Error_Msg_N ("representation item must appear after type is fully defined", N); return True; end if; else return False; end if; end Rep_Item_Too_Early; ----------------------- -- Rep_Item_Too_Late -- ----------------------- function Rep_Item_Too_Late (T : Entity_Id; N : Node_Id; FOnly : Boolean := False) return Boolean is S : Entity_Id; Parent_Type : Entity_Id; procedure No_Type_Rep_Item; -- Output message indicating that no type-related aspects can be -- specified due to some property of the parent type. procedure Too_Late; -- Output message for an aspect being specified too late -- Note that neither of the above errors is considered a serious one, -- since the effect is simply that we ignore the representation clause -- in these cases. -- Is this really true? In any case if we make this change we must -- document the requirement in the spec of Rep_Item_Too_Late that -- if True is returned, then the rep item must be completely ignored??? ---------------------- -- No_Type_Rep_Item -- ---------------------- procedure No_Type_Rep_Item is begin Error_Msg_N ("|type-related representation item not permitted!", N); end No_Type_Rep_Item; -------------- -- Too_Late -- -------------- procedure Too_Late is begin -- Other compilers seem more relaxed about rep items appearing too -- late. Since analysis tools typically don't care about rep items -- anyway, no reason to be too strict about this. if not Relaxed_RM_Semantics then Error_Msg_N ("|representation item appears too late!", N); end if; end Too_Late; -- Start of processing for Rep_Item_Too_Late begin -- First make sure entity is not frozen (RM 13.1(9)) if Is_Frozen (T) -- Exclude imported types, which may be frozen if they appear in a -- representation clause for a local type. and then not From_Limited_With (T) -- Exclude generated entities (not coming from source). The common -- case is when we generate a renaming which prematurely freezes the -- renamed internal entity, but we still want to be able to set copies -- of attribute values such as Size/Alignment. and then Comes_From_Source (T) then -- A self-referential aspect is illegal if it forces freezing the -- entity before the corresponding pragma has been analyzed. if Nkind_In (N, N_Attribute_Definition_Clause, N_Pragma) and then From_Aspect_Specification (N) then Error_Msg_NE ("aspect specification causes premature freezing of&", T, N); Set_Has_Delayed_Freeze (T, False); return True; end if; Too_Late; S := First_Subtype (T); if Present (Freeze_Node (S)) then if not Relaxed_RM_Semantics then Error_Msg_NE ("??no more representation items for }", Freeze_Node (S), S); end if; end if; return True; -- Check for case of untagged derived type whose parent either has -- primitive operations, or is a by reference type (RM 13.1(10)). In -- this case we do not output a Too_Late message, since there is no -- earlier point where the rep item could be placed to make it legal. elsif Is_Type (T) and then not FOnly and then Is_Derived_Type (T) and then not Is_Tagged_Type (T) then Parent_Type := Etype (Base_Type (T)); if Has_Primitive_Operations (Parent_Type) then No_Type_Rep_Item; if not Relaxed_RM_Semantics then Error_Msg_NE ("\parent type & has primitive operations!", N, Parent_Type); end if; return True; elsif Is_By_Reference_Type (Parent_Type) then No_Type_Rep_Item; if not Relaxed_RM_Semantics then Error_Msg_NE ("\parent type & is a by reference type!", N, Parent_Type); end if; return True; end if; end if; -- No error, but one more warning to consider. The RM (surprisingly) -- allows this pattern: -- type S is ... -- primitive operations for S -- type R is new S; -- rep clause for S -- Meaning that calls on the primitive operations of S for values of -- type R may require possibly expensive implicit conversion operations. -- This is not an error, but is worth a warning. if not Relaxed_RM_Semantics and then Is_Type (T) then declare DTL : constant Entity_Id := Derived_Type_Link (Base_Type (T)); begin if Present (DTL) and then Has_Primitive_Operations (Base_Type (T)) -- For now, do not generate this warning for the case of aspect -- specification using Ada 2012 syntax, since we get wrong -- messages we do not understand. The whole business of derived -- types and rep items seems a bit confused when aspects are -- used, since the aspects are not evaluated till freeze time. and then not From_Aspect_Specification (N) then Error_Msg_Sloc := Sloc (DTL); Error_Msg_N ("representation item for& appears after derived type " & "declaration#??", N); Error_Msg_NE ("\may result in implicit conversions for primitive " & "operations of&??", N, T); Error_Msg_NE ("\to change representations when called with arguments " & "of type&??", N, DTL); end if; end; end if; -- No error, link item into head of chain of rep items for the entity, -- but avoid chaining if we have an overloadable entity, and the pragma -- is one that can apply to multiple overloaded entities. if Is_Overloadable (T) and then Nkind (N) = N_Pragma then declare Pname : constant Name_Id := Pragma_Name (N); begin if Nam_In (Pname, Name_Convention, Name_Import, Name_Export, Name_External, Name_Interface) then return False; end if; end; end if; Record_Rep_Item (T, N); return False; end Rep_Item_Too_Late; ------------------------------------- -- Replace_Type_References_Generic -- ------------------------------------- procedure Replace_Type_References_Generic (N : Node_Id; T : Entity_Id) is TName : constant Name_Id := Chars (T); function Replace_Type_Ref (N : Node_Id) return Traverse_Result; -- Processes a single node in the traversal procedure below, checking -- if node N should be replaced, and if so, doing the replacement. function Visible_Component (Comp : Name_Id) return Entity_Id; -- Given an identifier in the expression, check whether there is a -- discriminant or component of the type that is directy visible, and -- rewrite it as the corresponding selected component of the formal of -- the subprogram. The entity is located by a sequential search, which -- seems acceptable given the typical size of component lists and check -- expressions. Possible optimization ??? ---------------------- -- Replace_Type_Ref -- ---------------------- function Replace_Type_Ref (N : Node_Id) return Traverse_Result is Loc : constant Source_Ptr := Sloc (N); procedure Add_Prefix (Ref : Node_Id; Comp : Entity_Id); -- Add the proper prefix to a reference to a component of the type -- when it is not already a selected component. ---------------- -- Add_Prefix -- ---------------- procedure Add_Prefix (Ref : Node_Id; Comp : Entity_Id) is begin Rewrite (Ref, Make_Selected_Component (Loc, Prefix => New_Occurrence_Of (T, Loc), Selector_Name => New_Occurrence_Of (Comp, Loc))); Replace_Type_Reference (Prefix (Ref)); end Add_Prefix; -- Local variables Comp : Entity_Id; Pref : Node_Id; Scop : Entity_Id; -- Start of processing for Replace_Type_Ref begin if Nkind (N) = N_Identifier then -- If not the type name, check whether it is a reference to some -- other type, which must be frozen before the predicate function -- is analyzed, i.e. before the freeze node of the type to which -- the predicate applies. if Chars (N) /= TName then if Present (Current_Entity (N)) and then Is_Type (Current_Entity (N)) then Freeze_Before (Freeze_Node (T), Current_Entity (N)); end if; -- The components of the type are directly visible and can -- be referenced without a prefix. if Nkind (Parent (N)) = N_Selected_Component then null; -- In expression C (I), C may be a directly visible function -- or a visible component that has an array type. Disambiguate -- by examining the component type. elsif Nkind (Parent (N)) = N_Indexed_Component and then N = Prefix (Parent (N)) then Comp := Visible_Component (Chars (N)); if Present (Comp) and then Is_Array_Type (Etype (Comp)) then Add_Prefix (N, Comp); end if; else Comp := Visible_Component (Chars (N)); if Present (Comp) then Add_Prefix (N, Comp); end if; end if; return Skip; -- Otherwise do the replacement and we are done with this node else Replace_Type_Reference (N); return Skip; end if; -- Case of selected component (which is what a qualification looks -- like in the unanalyzed tree, which is what we have. elsif Nkind (N) = N_Selected_Component then -- If selector name is not our type, keeping going (we might still -- have an occurrence of the type in the prefix). if Nkind (Selector_Name (N)) /= N_Identifier or else Chars (Selector_Name (N)) /= TName then return OK; -- Selector name is our type, check qualification else -- Loop through scopes and prefixes, doing comparison Scop := Current_Scope; Pref := Prefix (N); loop -- Continue if no more scopes or scope with no name if No (Scop) or else Nkind (Scop) not in N_Has_Chars then return OK; end if; -- Do replace if prefix is an identifier matching the scope -- that we are currently looking at. if Nkind (Pref) = N_Identifier and then Chars (Pref) = Chars (Scop) then Replace_Type_Reference (N); return Skip; end if; -- Go check scope above us if prefix is itself of the form -- of a selected component, whose selector matches the scope -- we are currently looking at. if Nkind (Pref) = N_Selected_Component and then Nkind (Selector_Name (Pref)) = N_Identifier and then Chars (Selector_Name (Pref)) = Chars (Scop) then Scop := Scope (Scop); Pref := Prefix (Pref); -- For anything else, we don't have a match, so keep on -- going, there are still some weird cases where we may -- still have a replacement within the prefix. else return OK; end if; end loop; end if; -- Continue for any other node kind else return OK; end if; end Replace_Type_Ref; procedure Replace_Type_Refs is new Traverse_Proc (Replace_Type_Ref); ----------------------- -- Visible_Component -- ----------------------- function Visible_Component (Comp : Name_Id) return Entity_Id is E : Entity_Id; begin if Ekind (T) /= E_Record_Type then return Empty; else E := First_Entity (T); while Present (E) loop if Comes_From_Source (E) and then Chars (E) = Comp then return E; end if; Next_Entity (E); end loop; return Empty; end if; end Visible_Component; -- Start of processing for Replace_Type_References_Generic begin Replace_Type_Refs (N); end Replace_Type_References_Generic; -------------------------------- -- Resolve_Aspect_Expressions -- -------------------------------- procedure Resolve_Aspect_Expressions (E : Entity_Id) is ASN : Node_Id; A_Id : Aspect_Id; Expr : Node_Id; function Resolve_Name (N : Node_Id) return Traverse_Result; -- Verify that all identifiers in the expression, with the exception -- of references to the current entity, denote visible entities. This -- is done only to detect visibility errors, as the expression will be -- properly analyzed/expanded during analysis of the predicate function -- body. We omit quantified expressions from this test, given that they -- introduce a local identifier that would require proper expansion to -- handle properly. ------------------ -- Resolve_Name -- ------------------ function Resolve_Name (N : Node_Id) return Traverse_Result is begin if Nkind (N) = N_Selected_Component then if Nkind (Prefix (N)) = N_Identifier and then Chars (Prefix (N)) /= Chars (E) then Find_Selected_Component (N); end if; return Skip; elsif Nkind (N) = N_Identifier and then Chars (N) /= Chars (E) then Find_Direct_Name (N); Set_Entity (N, Empty); elsif Nkind (N) = N_Quantified_Expression then return Skip; end if; return OK; end Resolve_Name; procedure Resolve_Aspect_Expression is new Traverse_Proc (Resolve_Name); -- Start of processing for Resolve_Aspect_Expressions begin ASN := First_Rep_Item (E); while Present (ASN) loop if Nkind (ASN) = N_Aspect_Specification and then Entity (ASN) = E then A_Id := Get_Aspect_Id (ASN); Expr := Expression (ASN); case A_Id is -- For now we only deal with aspects that do not generate -- subprograms, or that may mention current instances of -- types. These will require special handling (???TBD). when Aspect_Predicate | Aspect_Predicate_Failure | Aspect_Invariant => null; when Aspect_Dynamic_Predicate | Aspect_Static_Predicate => -- Build predicate function specification and preanalyze -- expression after type replacement. if No (Predicate_Function (E)) then declare FDecl : constant Node_Id := Build_Predicate_Function_Declaration (E); pragma Unreferenced (FDecl); begin Resolve_Aspect_Expression (Expr); end; end if; when Pre_Post_Aspects => null; when Aspect_Iterable => if Nkind (Expr) = N_Aggregate then declare Assoc : Node_Id; begin Assoc := First (Component_Associations (Expr)); while Present (Assoc) loop Find_Direct_Name (Expression (Assoc)); Next (Assoc); end loop; end; end if; when others => if Present (Expr) then case Aspect_Argument (A_Id) is when Expression | Optional_Expression => Analyze_And_Resolve (Expression (ASN)); when Name | Optional_Name => if Nkind (Expr) = N_Identifier then Find_Direct_Name (Expr); elsif Nkind (Expr) = N_Selected_Component then Find_Selected_Component (Expr); else null; end if; end case; end if; end case; end if; ASN := Next_Rep_Item (ASN); end loop; end Resolve_Aspect_Expressions; ------------------------- -- Same_Representation -- ------------------------- function Same_Representation (Typ1, Typ2 : Entity_Id) return Boolean is T1 : constant Entity_Id := Underlying_Type (Typ1); T2 : constant Entity_Id := Underlying_Type (Typ2); begin -- A quick check, if base types are the same, then we definitely have -- the same representation, because the subtype specific representation -- attributes (Size and Alignment) do not affect representation from -- the point of view of this test. if Base_Type (T1) = Base_Type (T2) then return True; elsif Is_Private_Type (Base_Type (T2)) and then Base_Type (T1) = Full_View (Base_Type (T2)) then return True; end if; -- Tagged types never have differing representations if Is_Tagged_Type (T1) then return True; end if; -- Representations are definitely different if conventions differ if Convention (T1) /= Convention (T2) then return False; end if; -- Representations are different if component alignments or scalar -- storage orders differ. if (Is_Record_Type (T1) or else Is_Array_Type (T1)) and then (Is_Record_Type (T2) or else Is_Array_Type (T2)) and then (Component_Alignment (T1) /= Component_Alignment (T2) or else Reverse_Storage_Order (T1) /= Reverse_Storage_Order (T2)) then return False; end if; -- For arrays, the only real issue is component size. If we know the -- component size for both arrays, and it is the same, then that's -- good enough to know we don't have a change of representation. if Is_Array_Type (T1) then if Known_Component_Size (T1) and then Known_Component_Size (T2) and then Component_Size (T1) = Component_Size (T2) then return True; end if; end if; -- Types definitely have same representation if neither has non-standard -- representation since default representations are always consistent. -- If only one has non-standard representation, and the other does not, -- then we consider that they do not have the same representation. They -- might, but there is no way of telling early enough. if Has_Non_Standard_Rep (T1) then if not Has_Non_Standard_Rep (T2) then return False; end if; else return not Has_Non_Standard_Rep (T2); end if; -- Here the two types both have non-standard representation, and we need -- to determine if they have the same non-standard representation. -- For arrays, we simply need to test if the component sizes are the -- same. Pragma Pack is reflected in modified component sizes, so this -- check also deals with pragma Pack. if Is_Array_Type (T1) then return Component_Size (T1) = Component_Size (T2); -- Tagged types always have the same representation, because it is not -- possible to specify different representations for common fields. elsif Is_Tagged_Type (T1) then return True; -- Case of record types elsif Is_Record_Type (T1) then -- Packed status must conform if Is_Packed (T1) /= Is_Packed (T2) then return False; -- Otherwise we must check components. Typ2 maybe a constrained -- subtype with fewer components, so we compare the components -- of the base types. else Record_Case : declare CD1, CD2 : Entity_Id; function Same_Rep return Boolean; -- CD1 and CD2 are either components or discriminants. This -- function tests whether they have the same representation. -------------- -- Same_Rep -- -------------- function Same_Rep return Boolean is begin if No (Component_Clause (CD1)) then return No (Component_Clause (CD2)); else -- Note: at this point, component clauses have been -- normalized to the default bit order, so that the -- comparison of Component_Bit_Offsets is meaningful. return Present (Component_Clause (CD2)) and then Component_Bit_Offset (CD1) = Component_Bit_Offset (CD2) and then Esize (CD1) = Esize (CD2); end if; end Same_Rep; -- Start of processing for Record_Case begin if Has_Discriminants (T1) then -- The number of discriminants may be different if the -- derived type has fewer (constrained by values). The -- invisible discriminants retain the representation of -- the original, so the discrepancy does not per se -- indicate a different representation. CD1 := First_Discriminant (T1); CD2 := First_Discriminant (T2); while Present (CD1) and then Present (CD2) loop if not Same_Rep then return False; else Next_Discriminant (CD1); Next_Discriminant (CD2); end if; end loop; end if; CD1 := First_Component (Underlying_Type (Base_Type (T1))); CD2 := First_Component (Underlying_Type (Base_Type (T2))); while Present (CD1) loop if not Same_Rep then return False; else Next_Component (CD1); Next_Component (CD2); end if; end loop; return True; end Record_Case; end if; -- For enumeration types, we must check each literal to see if the -- representation is the same. Note that we do not permit enumeration -- representation clauses for Character and Wide_Character, so these -- cases were already dealt with. elsif Is_Enumeration_Type (T1) then Enumeration_Case : declare L1, L2 : Entity_Id; begin L1 := First_Literal (T1); L2 := First_Literal (T2); while Present (L1) loop if Enumeration_Rep (L1) /= Enumeration_Rep (L2) then return False; else Next_Literal (L1); Next_Literal (L2); end if; end loop; return True; end Enumeration_Case; -- Any other types have the same representation for these purposes else return True; end if; end Same_Representation; -------------------------------- -- Resolve_Iterable_Operation -- -------------------------------- procedure Resolve_Iterable_Operation (N : Node_Id; Cursor : Entity_Id; Typ : Entity_Id; Nam : Name_Id) is Ent : Entity_Id; F1 : Entity_Id; F2 : Entity_Id; begin if not Is_Overloaded (N) then if not Is_Entity_Name (N) or else Ekind (Entity (N)) /= E_Function or else Scope (Entity (N)) /= Scope (Typ) or else No (First_Formal (Entity (N))) or else Etype (First_Formal (Entity (N))) /= Typ then Error_Msg_N ("iterable primitive must be local function name " & "whose first formal is an iterable type", N); return; end if; Ent := Entity (N); F1 := First_Formal (Ent); if Nam = Name_First then -- First (Container) => Cursor if Etype (Ent) /= Cursor then Error_Msg_N ("primitive for First must yield a curosr", N); end if; elsif Nam = Name_Next then -- Next (Container, Cursor) => Cursor F2 := Next_Formal (F1); if Etype (F2) /= Cursor or else Etype (Ent) /= Cursor or else Present (Next_Formal (F2)) then Error_Msg_N ("no match for Next iterable primitive", N); end if; elsif Nam = Name_Has_Element then -- Has_Element (Container, Cursor) => Boolean F2 := Next_Formal (F1); if Etype (F2) /= Cursor or else Etype (Ent) /= Standard_Boolean or else Present (Next_Formal (F2)) then Error_Msg_N ("no match for Has_Element iterable primitive", N); end if; elsif Nam = Name_Element then F2 := Next_Formal (F1); if No (F2) or else Etype (F2) /= Cursor or else Present (Next_Formal (F2)) then Error_Msg_N ("no match for Element iterable primitive", N); end if; null; else raise Program_Error; end if; else -- Overloaded case: find subprogram with proper signature. -- Caller will report error if no match is found. declare I : Interp_Index; It : Interp; begin Get_First_Interp (N, I, It); while Present (It.Typ) loop if Ekind (It.Nam) = E_Function and then Scope (It.Nam) = Scope (Typ) and then Etype (First_Formal (It.Nam)) = Typ then F1 := First_Formal (It.Nam); if Nam = Name_First then if Etype (It.Nam) = Cursor and then No (Next_Formal (F1)) then Set_Entity (N, It.Nam); exit; end if; elsif Nam = Name_Next then F2 := Next_Formal (F1); if Present (F2) and then No (Next_Formal (F2)) and then Etype (F2) = Cursor and then Etype (It.Nam) = Cursor then Set_Entity (N, It.Nam); exit; end if; elsif Nam = Name_Has_Element then F2 := Next_Formal (F1); if Present (F2) and then No (Next_Formal (F2)) and then Etype (F2) = Cursor and then Etype (It.Nam) = Standard_Boolean then Set_Entity (N, It.Nam); F2 := Next_Formal (F1); exit; end if; elsif Nam = Name_Element then F2 := Next_Formal (F1); if Present (F2) and then No (Next_Formal (F2)) and then Etype (F2) = Cursor then Set_Entity (N, It.Nam); exit; end if; end if; end if; Get_Next_Interp (I, It); end loop; end; end if; end Resolve_Iterable_Operation; ---------------- -- Set_Biased -- ---------------- procedure Set_Biased (E : Entity_Id; N : Node_Id; Msg : String; Biased : Boolean := True) is begin if Biased then Set_Has_Biased_Representation (E); if Warn_On_Biased_Representation then Error_Msg_NE ("?B?" & Msg & " forces biased representation for&", N, E); end if; end if; end Set_Biased; -------------------- -- Set_Enum_Esize -- -------------------- procedure Set_Enum_Esize (T : Entity_Id) is Lo : Uint; Hi : Uint; Sz : Nat; begin Init_Alignment (T); -- Find the minimum standard size (8,16,32,64) that fits Lo := Enumeration_Rep (Entity (Type_Low_Bound (T))); Hi := Enumeration_Rep (Entity (Type_High_Bound (T))); if Lo < 0 then if Lo >= -Uint_2**07 and then Hi < Uint_2**07 then Sz := Standard_Character_Size; -- May be > 8 on some targets elsif Lo >= -Uint_2**15 and then Hi < Uint_2**15 then Sz := 16; elsif Lo >= -Uint_2**31 and then Hi < Uint_2**31 then Sz := 32; else pragma Assert (Lo >= -Uint_2**63 and then Hi < Uint_2**63); Sz := 64; end if; else if Hi < Uint_2**08 then Sz := Standard_Character_Size; -- May be > 8 on some targets elsif Hi < Uint_2**16 then Sz := 16; elsif Hi < Uint_2**32 then Sz := 32; else pragma Assert (Hi < Uint_2**63); Sz := 64; end if; end if; -- That minimum is the proper size unless we have a foreign convention -- and the size required is 32 or less, in which case we bump the size -- up to 32. This is required for C and C++ and seems reasonable for -- all other foreign conventions. if Has_Foreign_Convention (T) and then Esize (T) < Standard_Integer_Size -- Don't do this if Short_Enums on target and then not Target_Short_Enums then Init_Esize (T, Standard_Integer_Size); else Init_Esize (T, Sz); end if; end Set_Enum_Esize; ----------------------------- -- Uninstall_Discriminants -- ----------------------------- procedure Uninstall_Discriminants (E : Entity_Id) is Disc : Entity_Id; Prev : Entity_Id; Outer : Entity_Id; begin -- Discriminants have been made visible for type declarations and -- protected type declarations, not for subtype declarations. if Nkind (Parent (E)) /= N_Subtype_Declaration then Disc := First_Discriminant (E); while Present (Disc) loop if Disc /= Current_Entity (Disc) then Prev := Current_Entity (Disc); while Present (Prev) and then Present (Homonym (Prev)) and then Homonym (Prev) /= Disc loop Prev := Homonym (Prev); end loop; else Prev := Empty; end if; Set_Is_Immediately_Visible (Disc, False); Outer := Homonym (Disc); while Present (Outer) and then Scope (Outer) = E loop Outer := Homonym (Outer); end loop; -- Reset homonym link of other entities, but do not modify link -- between entities in current scope, so that the back end can -- have a proper count of local overloadings. if No (Prev) then Set_Name_Entity_Id (Chars (Disc), Outer); elsif Scope (Prev) /= Scope (Disc) then Set_Homonym (Prev, Outer); end if; Next_Discriminant (Disc); end loop; end if; end Uninstall_Discriminants; ------------------------------------------- -- Uninstall_Discriminants_And_Pop_Scope -- ------------------------------------------- procedure Uninstall_Discriminants_And_Pop_Scope (E : Entity_Id) is begin if Has_Discriminants (E) then Uninstall_Discriminants (E); Pop_Scope; end if; end Uninstall_Discriminants_And_Pop_Scope; ------------------------------ -- Validate_Address_Clauses -- ------------------------------ procedure Validate_Address_Clauses is function Offset_Value (Expr : Node_Id) return Uint; -- Given an Address attribute reference, return the value in bits of its -- offset from the first bit of the underlying entity, or 0 if it is not -- known at compile time. ------------------ -- Offset_Value -- ------------------ function Offset_Value (Expr : Node_Id) return Uint is N : Node_Id := Prefix (Expr); Off : Uint; Val : Uint := Uint_0; begin -- Climb the prefix chain and compute the cumulative offset loop if Is_Entity_Name (N) then return Val; elsif Nkind (N) = N_Selected_Component then Off := Component_Bit_Offset (Entity (Selector_Name (N))); if Off /= No_Uint and then Off >= Uint_0 then Val := Val + Off; N := Prefix (N); else return Uint_0; end if; elsif Nkind (N) = N_Indexed_Component then Off := Indexed_Component_Bit_Offset (N); if Off /= No_Uint then Val := Val + Off; N := Prefix (N); else return Uint_0; end if; else return Uint_0; end if; end loop; end Offset_Value; -- Start of processing for Validate_Address_Clauses begin for J in Address_Clause_Checks.First .. Address_Clause_Checks.Last loop declare ACCR : Address_Clause_Check_Record renames Address_Clause_Checks.Table (J); Expr : Node_Id; X_Alignment : Uint; Y_Alignment : Uint; X_Size : Uint; Y_Size : Uint; X_Offs : Uint; begin -- Skip processing of this entry if warning already posted if not Address_Warning_Posted (ACCR.N) then Expr := Original_Node (Expression (ACCR.N)); -- Get alignments, sizes and offset, if any X_Alignment := Alignment (ACCR.X); X_Size := Esize (ACCR.X); if Present (ACCR.Y) then Y_Alignment := Alignment (ACCR.Y); Y_Size := Esize (ACCR.Y); end if; if ACCR.Off and then Nkind (Expr) = N_Attribute_Reference and then Attribute_Name (Expr) = Name_Address then X_Offs := Offset_Value (Expr); else X_Offs := Uint_0; end if; -- Check for known value not multiple of alignment if No (ACCR.Y) then if not Alignment_Checks_Suppressed (ACCR.X) and then X_Alignment /= 0 and then ACCR.A mod X_Alignment /= 0 then Error_Msg_NE ("??specified address for& is inconsistent with " & "alignment", ACCR.N, ACCR.X); Error_Msg_N ("\??program execution may be erroneous (RM 13.3(27))", ACCR.N); Error_Msg_Uint_1 := X_Alignment; Error_Msg_NE ("\??alignment of & is ^", ACCR.N, ACCR.X); end if; -- Check for large object overlaying smaller one elsif Y_Size > Uint_0 and then X_Size > Uint_0 and then X_Offs + X_Size > Y_Size then Error_Msg_NE ("??& overlays smaller object", ACCR.N, ACCR.X); Error_Msg_N ("\??program execution may be erroneous", ACCR.N); Error_Msg_Uint_1 := X_Size; Error_Msg_NE ("\??size of & is ^", ACCR.N, ACCR.X); Error_Msg_Uint_1 := Y_Size; Error_Msg_NE ("\??size of & is ^", ACCR.N, ACCR.Y); if Y_Size >= X_Size then Error_Msg_Uint_1 := X_Offs; Error_Msg_NE ("\??but offset of & is ^", ACCR.N, ACCR.X); end if; -- Check for inadequate alignment, both of the base object -- and of the offset, if any. We only do this check if the -- run-time Alignment_Check is active. No point in warning -- if this check has been suppressed (or is suppressed by -- default in the non-strict alignment machine case). -- Note: we do not check the alignment if we gave a size -- warning, since it would likely be redundant. elsif not Alignment_Checks_Suppressed (ACCR.X) and then Y_Alignment /= Uint_0 and then (Y_Alignment < X_Alignment or else (ACCR.Off and then Nkind (Expr) = N_Attribute_Reference and then Attribute_Name (Expr) = Name_Address and then Has_Compatible_Alignment (ACCR.X, Prefix (Expr), True) /= Known_Compatible)) then Error_Msg_NE ("??specified address for& may be inconsistent with " & "alignment", ACCR.N, ACCR.X); Error_Msg_N ("\??program execution may be erroneous (RM 13.3(27))", ACCR.N); Error_Msg_Uint_1 := X_Alignment; Error_Msg_NE ("\??alignment of & is ^", ACCR.N, ACCR.X); Error_Msg_Uint_1 := Y_Alignment; Error_Msg_NE ("\??alignment of & is ^", ACCR.N, ACCR.Y); if Y_Alignment >= X_Alignment then Error_Msg_N ("\??but offset is not multiple of alignment", ACCR.N); end if; end if; end if; end; end loop; end Validate_Address_Clauses; --------------------------- -- Validate_Independence -- --------------------------- procedure Validate_Independence is SU : constant Uint := UI_From_Int (System_Storage_Unit); N : Node_Id; E : Entity_Id; IC : Boolean; Comp : Entity_Id; Addr : Node_Id; P : Node_Id; procedure Check_Array_Type (Atyp : Entity_Id); -- Checks if the array type Atyp has independent components, and -- if not, outputs an appropriate set of error messages. procedure No_Independence; -- Output message that independence cannot be guaranteed function OK_Component (C : Entity_Id) return Boolean; -- Checks one component to see if it is independently accessible, and -- if so yields True, otherwise yields False if independent access -- cannot be guaranteed. This is a conservative routine, it only -- returns True if it knows for sure, it returns False if it knows -- there is a problem, or it cannot be sure there is no problem. procedure Reason_Bad_Component (C : Entity_Id); -- Outputs continuation message if a reason can be determined for -- the component C being bad. ---------------------- -- Check_Array_Type -- ---------------------- procedure Check_Array_Type (Atyp : Entity_Id) is Ctyp : constant Entity_Id := Component_Type (Atyp); begin -- OK if no alignment clause, no pack, and no component size if not Has_Component_Size_Clause (Atyp) and then not Has_Alignment_Clause (Atyp) and then not Is_Packed (Atyp) then return; end if; -- Case of component size is greater than or equal to 64 and the -- alignment of the array is at least as large as the alignment -- of the component. We are definitely OK in this situation. if Known_Component_Size (Atyp) and then Component_Size (Atyp) >= 64 and then Known_Alignment (Atyp) and then Known_Alignment (Ctyp) and then Alignment (Atyp) >= Alignment (Ctyp) then return; end if; -- Check actual component size if not Known_Component_Size (Atyp) or else not (Addressable (Component_Size (Atyp)) and then Component_Size (Atyp) < 64) or else Component_Size (Atyp) mod Esize (Ctyp) /= 0 then No_Independence; -- Bad component size, check reason if Has_Component_Size_Clause (Atyp) then P := Get_Attribute_Definition_Clause (Atyp, Attribute_Component_Size); if Present (P) then Error_Msg_Sloc := Sloc (P); Error_Msg_N ("\because of Component_Size clause#", N); return; end if; end if; if Is_Packed (Atyp) then P := Get_Rep_Pragma (Atyp, Name_Pack); if Present (P) then Error_Msg_Sloc := Sloc (P); Error_Msg_N ("\because of pragma Pack#", N); return; end if; end if; -- No reason found, just return return; end if; -- Array type is OK independence-wise return; end Check_Array_Type; --------------------- -- No_Independence -- --------------------- procedure No_Independence is begin if Pragma_Name (N) = Name_Independent then Error_Msg_NE ("independence cannot be guaranteed for&", N, E); else Error_Msg_NE ("independent components cannot be guaranteed for&", N, E); end if; end No_Independence; ------------------ -- OK_Component -- ------------------ function OK_Component (C : Entity_Id) return Boolean is Rec : constant Entity_Id := Scope (C); Ctyp : constant Entity_Id := Etype (C); begin -- OK if no component clause, no Pack, and no alignment clause if No (Component_Clause (C)) and then not Is_Packed (Rec) and then not Has_Alignment_Clause (Rec) then return True; end if; -- Here we look at the actual component layout. A component is -- addressable if its size is a multiple of the Esize of the -- component type, and its starting position in the record has -- appropriate alignment, and the record itself has appropriate -- alignment to guarantee the component alignment. -- Make sure sizes are static, always assume the worst for any -- cases where we cannot check static values. if not (Known_Static_Esize (C) and then Known_Static_Esize (Ctyp)) then return False; end if; -- Size of component must be addressable or greater than 64 bits -- and a multiple of bytes. if not Addressable (Esize (C)) and then Esize (C) < Uint_64 then return False; end if; -- Check size is proper multiple if Esize (C) mod Esize (Ctyp) /= 0 then return False; end if; -- Check alignment of component is OK if not Known_Component_Bit_Offset (C) or else Component_Bit_Offset (C) < Uint_0 or else Component_Bit_Offset (C) mod Esize (Ctyp) /= 0 then return False; end if; -- Check alignment of record type is OK if not Known_Alignment (Rec) or else (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0 then return False; end if; -- All tests passed, component is addressable return True; end OK_Component; -------------------------- -- Reason_Bad_Component -- -------------------------- procedure Reason_Bad_Component (C : Entity_Id) is Rec : constant Entity_Id := Scope (C); Ctyp : constant Entity_Id := Etype (C); begin -- If component clause present assume that's the problem if Present (Component_Clause (C)) then Error_Msg_Sloc := Sloc (Component_Clause (C)); Error_Msg_N ("\because of Component_Clause#", N); return; end if; -- If pragma Pack clause present, assume that's the problem if Is_Packed (Rec) then P := Get_Rep_Pragma (Rec, Name_Pack); if Present (P) then Error_Msg_Sloc := Sloc (P); Error_Msg_N ("\because of pragma Pack#", N); return; end if; end if; -- See if record has bad alignment clause if Has_Alignment_Clause (Rec) and then Known_Alignment (Rec) and then (Alignment (Rec) * SU) mod Esize (Ctyp) /= 0 then P := Get_Attribute_Definition_Clause (Rec, Attribute_Alignment); if Present (P) then Error_Msg_Sloc := Sloc (P); Error_Msg_N ("\because of Alignment clause#", N); end if; end if; -- Couldn't find a reason, so return without a message return; end Reason_Bad_Component; -- Start of processing for Validate_Independence begin for J in Independence_Checks.First .. Independence_Checks.Last loop N := Independence_Checks.Table (J).N; E := Independence_Checks.Table (J).E; IC := Pragma_Name (N) = Name_Independent_Components; -- Deal with component case if Ekind (E) = E_Discriminant or else Ekind (E) = E_Component then if not OK_Component (E) then No_Independence; Reason_Bad_Component (E); goto Continue; end if; end if; -- Deal with record with Independent_Components if IC and then Is_Record_Type (E) then Comp := First_Component_Or_Discriminant (E); while Present (Comp) loop if not OK_Component (Comp) then No_Independence; Reason_Bad_Component (Comp); goto Continue; end if; Next_Component_Or_Discriminant (Comp); end loop; end if; -- Deal with address clause case if Is_Object (E) then Addr := Address_Clause (E); if Present (Addr) then No_Independence; Error_Msg_Sloc := Sloc (Addr); Error_Msg_N ("\because of Address clause#", N); goto Continue; end if; end if; -- Deal with independent components for array type if IC and then Is_Array_Type (E) then Check_Array_Type (E); end if; -- Deal with independent components for array object if IC and then Is_Object (E) and then Is_Array_Type (Etype (E)) then Check_Array_Type (Etype (E)); end if; <> null; end loop; end Validate_Independence; ------------------------------ -- Validate_Iterable_Aspect -- ------------------------------ procedure Validate_Iterable_Aspect (Typ : Entity_Id; ASN : Node_Id) is Assoc : Node_Id; Expr : Node_Id; Prim : Node_Id; Cursor : constant Entity_Id := Get_Cursor_Type (ASN, Typ); First_Id : Entity_Id; Next_Id : Entity_Id; Has_Element_Id : Entity_Id; Element_Id : Entity_Id; begin -- If previous error aspect is unusable if Cursor = Any_Type then return; end if; First_Id := Empty; Next_Id := Empty; Has_Element_Id := Empty; Element_Id := Empty; -- Each expression must resolve to a function with the proper signature Assoc := First (Component_Associations (Expression (ASN))); while Present (Assoc) loop Expr := Expression (Assoc); Analyze (Expr); Prim := First (Choices (Assoc)); if Nkind (Prim) /= N_Identifier or else Present (Next (Prim)) then Error_Msg_N ("illegal name in association", Prim); elsif Chars (Prim) = Name_First then Resolve_Iterable_Operation (Expr, Cursor, Typ, Name_First); First_Id := Entity (Expr); elsif Chars (Prim) = Name_Next then Resolve_Iterable_Operation (Expr, Cursor, Typ, Name_Next); Next_Id := Entity (Expr); elsif Chars (Prim) = Name_Has_Element then Resolve_Iterable_Operation (Expr, Cursor, Typ, Name_Has_Element); Has_Element_Id := Entity (Expr); elsif Chars (Prim) = Name_Element then Resolve_Iterable_Operation (Expr, Cursor, Typ, Name_Element); Element_Id := Entity (Expr); else Error_Msg_N ("invalid name for iterable function", Prim); end if; Next (Assoc); end loop; if No (First_Id) then Error_Msg_N ("match for First primitive not found", ASN); elsif No (Next_Id) then Error_Msg_N ("match for Next primitive not found", ASN); elsif No (Has_Element_Id) then Error_Msg_N ("match for Has_Element primitive not found", ASN); elsif No (Element_Id) then null; -- Optional. end if; end Validate_Iterable_Aspect; ----------------------------------- -- Validate_Unchecked_Conversion -- ----------------------------------- procedure Validate_Unchecked_Conversion (N : Node_Id; Act_Unit : Entity_Id) is Source : Entity_Id; Target : Entity_Id; Vnode : Node_Id; begin -- Obtain source and target types. Note that we call Ancestor_Subtype -- here because the processing for generic instantiation always makes -- subtypes, and we want the original frozen actual types. -- If we are dealing with private types, then do the check on their -- fully declared counterparts if the full declarations have been -- encountered (they don't have to be visible, but they must exist). Source := Ancestor_Subtype (Etype (First_Formal (Act_Unit))); if Is_Private_Type (Source) and then Present (Underlying_Type (Source)) then Source := Underlying_Type (Source); end if; Target := Ancestor_Subtype (Etype (Act_Unit)); -- If either type is generic, the instantiation happens within a generic -- unit, and there is nothing to check. The proper check will happen -- when the enclosing generic is instantiated. if Is_Generic_Type (Source) or else Is_Generic_Type (Target) then return; end if; if Is_Private_Type (Target) and then Present (Underlying_Type (Target)) then Target := Underlying_Type (Target); end if; -- Source may be unconstrained array, but not target, except in relaxed -- semantics mode. if Is_Array_Type (Target) and then not Is_Constrained (Target) and then not Relaxed_RM_Semantics then Error_Msg_N ("unchecked conversion to unconstrained array not allowed", N); return; end if; -- Warn if conversion between two different convention pointers if Is_Access_Type (Target) and then Is_Access_Type (Source) and then Convention (Target) /= Convention (Source) and then Warn_On_Unchecked_Conversion then -- Give warnings for subprogram pointers only on most targets if Is_Access_Subprogram_Type (Target) or else Is_Access_Subprogram_Type (Source) then Error_Msg_N ("?z?conversion between pointers with different conventions!", N); end if; end if; -- Warn if one of the operands is Ada.Calendar.Time. Do not emit a -- warning when compiling GNAT-related sources. if Warn_On_Unchecked_Conversion and then not In_Predefined_Unit (N) and then RTU_Loaded (Ada_Calendar) and then (Chars (Source) = Name_Time or else Chars (Target) = Name_Time) then -- If Ada.Calendar is loaded and the name of one of the operands is -- Time, there is a good chance that this is Ada.Calendar.Time. declare Calendar_Time : constant Entity_Id := Full_View (RTE (RO_CA_Time)); begin pragma Assert (Present (Calendar_Time)); if Source = Calendar_Time or else Target = Calendar_Time then Error_Msg_N ("?z?representation of 'Time values may change between " & "'G'N'A'T versions", N); end if; end; end if; -- Make entry in unchecked conversion table for later processing by -- Validate_Unchecked_Conversions, which will check sizes and alignments -- (using values set by the back end where possible). This is only done -- if the appropriate warning is active. if Warn_On_Unchecked_Conversion then Unchecked_Conversions.Append (New_Val => UC_Entry'(Eloc => Sloc (N), Source => Source, Target => Target, Act_Unit => Act_Unit)); -- If both sizes are known statically now, then back-end annotation -- is not required to do a proper check but if either size is not -- known statically, then we need the annotation. if Known_Static_RM_Size (Source) and then Known_Static_RM_Size (Target) then null; else Back_Annotate_Rep_Info := True; end if; end if; -- If unchecked conversion to access type, and access type is declared -- in the same unit as the unchecked conversion, then set the flag -- No_Strict_Aliasing (no strict aliasing is implicit here) if Is_Access_Type (Target) and then In_Same_Source_Unit (Target, N) then Set_No_Strict_Aliasing (Implementation_Base_Type (Target)); end if; -- Generate N_Validate_Unchecked_Conversion node for back end in case -- the back end needs to perform special validation checks. -- Shouldn't this be in Exp_Ch13, since the check only gets done if we -- have full expansion and the back end is called ??? Vnode := Make_Validate_Unchecked_Conversion (Sloc (N)); Set_Source_Type (Vnode, Source); Set_Target_Type (Vnode, Target); -- If the unchecked conversion node is in a list, just insert before it. -- If not we have some strange case, not worth bothering about. if Is_List_Member (N) then Insert_After (N, Vnode); end if; end Validate_Unchecked_Conversion; ------------------------------------ -- Validate_Unchecked_Conversions -- ------------------------------------ procedure Validate_Unchecked_Conversions is begin for N in Unchecked_Conversions.First .. Unchecked_Conversions.Last loop declare T : UC_Entry renames Unchecked_Conversions.Table (N); Act_Unit : constant Entity_Id := T.Act_Unit; Eloc : constant Source_Ptr := T.Eloc; Source : constant Entity_Id := T.Source; Target : constant Entity_Id := T.Target; Source_Siz : Uint; Target_Siz : Uint; begin -- Skip if function marked as warnings off if Warnings_Off (Act_Unit) then goto Continue; end if; -- This validation check, which warns if we have unequal sizes for -- unchecked conversion, and thus potentially implementation -- dependent semantics, is one of the few occasions on which we -- use the official RM size instead of Esize. See description in -- Einfo "Handling of Type'Size Values" for details. if Serious_Errors_Detected = 0 and then Known_Static_RM_Size (Source) and then Known_Static_RM_Size (Target) -- Don't do the check if warnings off for either type, note the -- deliberate use of OR here instead of OR ELSE to get the flag -- Warnings_Off_Used set for both types if appropriate. and then not (Has_Warnings_Off (Source) or Has_Warnings_Off (Target)) then Source_Siz := RM_Size (Source); Target_Siz := RM_Size (Target); if Source_Siz /= Target_Siz then Error_Msg ("?z?types for unchecked conversion have different sizes!", Eloc); if All_Errors_Mode then Error_Msg_Name_1 := Chars (Source); Error_Msg_Uint_1 := Source_Siz; Error_Msg_Name_2 := Chars (Target); Error_Msg_Uint_2 := Target_Siz; Error_Msg ("\size of % is ^, size of % is ^?z?", Eloc); Error_Msg_Uint_1 := UI_Abs (Source_Siz - Target_Siz); if Is_Discrete_Type (Source) and then Is_Discrete_Type (Target) then if Source_Siz > Target_Siz then Error_Msg ("\?z?^ high order bits of source will " & "be ignored!", Eloc); elsif Is_Unsigned_Type (Source) then Error_Msg ("\?z?source will be extended with ^ high order " & "zero bits!", Eloc); else Error_Msg ("\?z?source will be extended with ^ high order " & "sign bits!", Eloc); end if; elsif Source_Siz < Target_Siz then if Is_Discrete_Type (Target) then if Bytes_Big_Endian then Error_Msg ("\?z?target value will include ^ undefined " & "low order bits!", Eloc); else Error_Msg ("\?z?target value will include ^ undefined " & "high order bits!", Eloc); end if; else Error_Msg ("\?z?^ trailing bits of target value will be " & "undefined!", Eloc); end if; else pragma Assert (Source_Siz > Target_Siz); if Is_Discrete_Type (Source) then if Bytes_Big_Endian then Error_Msg ("\?z?^ low order bits of source will be " & "ignored!", Eloc); else Error_Msg ("\?z?^ high order bits of source will be " & "ignored!", Eloc); end if; else Error_Msg ("\?z?^ trailing bits of source will be " & "ignored!", Eloc); end if; end if; end if; end if; end if; -- If both types are access types, we need to check the alignment. -- If the alignment of both is specified, we can do it here. if Serious_Errors_Detected = 0 and then Is_Access_Type (Source) and then Is_Access_Type (Target) and then Target_Strict_Alignment and then Present (Designated_Type (Source)) and then Present (Designated_Type (Target)) then declare D_Source : constant Entity_Id := Designated_Type (Source); D_Target : constant Entity_Id := Designated_Type (Target); begin if Known_Alignment (D_Source) and then Known_Alignment (D_Target) then declare Source_Align : constant Uint := Alignment (D_Source); Target_Align : constant Uint := Alignment (D_Target); begin if Source_Align < Target_Align and then not Is_Tagged_Type (D_Source) -- Suppress warning if warnings suppressed on either -- type or either designated type. Note the use of -- OR here instead of OR ELSE. That is intentional, -- we would like to set flag Warnings_Off_Used in -- all types for which warnings are suppressed. and then not (Has_Warnings_Off (D_Source) or Has_Warnings_Off (D_Target) or Has_Warnings_Off (Source) or Has_Warnings_Off (Target)) then Error_Msg_Uint_1 := Target_Align; Error_Msg_Uint_2 := Source_Align; Error_Msg_Node_1 := D_Target; Error_Msg_Node_2 := D_Source; Error_Msg ("?z?alignment of & (^) is stricter than " & "alignment of & (^)!", Eloc); Error_Msg ("\?z?resulting access value may have invalid " & "alignment!", Eloc); end if; end; end if; end; end if; end; <> null; end loop; end Validate_Unchecked_Conversions; end Sem_Ch13;