+++ /dev/null
-------------------------------------------------------------------------------
--- --
--- GNAT COMPILER COMPONENTS --
--- --
--- S E M _ A G G R --
--- --
--- B o d y --
--- --
--- $Revision: 1.3.10.1 $
--- --
--- Copyright (C) 1992-2001 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 2, 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 COPYING. If not, write --
--- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
--- MA 02111-1307, USA. --
--- --
--- GNAT was originally developed by the GNAT team at New York University. --
--- Extensive contributions were provided by Ada Core Technologies Inc. --
--- --
-------------------------------------------------------------------------------
-
-with Atree; use Atree;
-with Checks; use Checks;
-with Einfo; use Einfo;
-with Elists; use Elists;
-with Errout; use Errout;
-with Exp_Util; use Exp_Util;
-with Freeze; use Freeze;
-with Itypes; use Itypes;
-with Namet; use Namet;
-with Nmake; use Nmake;
-with Nlists; use Nlists;
-with Opt; use Opt;
-with Sem; use Sem;
-with Sem_Cat; use Sem_Cat;
-with Sem_Ch8; use Sem_Ch8;
-with Sem_Ch13; use Sem_Ch13;
-with Sem_Eval; use Sem_Eval;
-with Sem_Res; use Sem_Res;
-with Sem_Util; use Sem_Util;
-with Sem_Type; use Sem_Type;
-with Sinfo; use Sinfo;
-with Snames; use Snames;
-with Stringt; use Stringt;
-with Stand; use Stand;
-with Tbuild; use Tbuild;
-with Uintp; use Uintp;
-
-with GNAT.Spelling_Checker; use GNAT.Spelling_Checker;
-
-package body Sem_Aggr is
-
- type Case_Bounds is record
- Choice_Lo : Node_Id;
- Choice_Hi : Node_Id;
- Choice_Node : Node_Id;
- end record;
-
- type Case_Table_Type is array (Nat range <>) of Case_Bounds;
- -- Table type used by Check_Case_Choices procedure
-
- -----------------------
- -- Local Subprograms --
- -----------------------
-
- procedure Sort_Case_Table (Case_Table : in out Case_Table_Type);
- -- Sort the Case Table using the Lower Bound of each Choice as the key.
- -- A simple insertion sort is used since the number of choices in a case
- -- statement of variant part will usually be small and probably in near
- -- sorted order.
-
- ------------------------------------------------------
- -- Subprograms used for RECORD AGGREGATE Processing --
- ------------------------------------------------------
-
- procedure Resolve_Record_Aggregate (N : Node_Id; Typ : Entity_Id);
- -- This procedure performs all the semantic checks required for record
- -- aggregates. Note that for aggregates analysis and resolution go
- -- hand in hand. Aggregate analysis has been delayed up to here and
- -- it is done while resolving the aggregate.
- --
- -- N is the N_Aggregate node.
- -- Typ is the record type for the aggregate resolution
- --
- -- While performing the semantic checks, this procedure
- -- builds a new Component_Association_List where each record field
- -- appears alone in a Component_Choice_List along with its corresponding
- -- expression. The record fields in the Component_Association_List
- -- appear in the same order in which they appear in the record type Typ.
- --
- -- Once this new Component_Association_List is built and all the
- -- semantic checks performed, the original aggregate subtree is replaced
- -- with the new named record aggregate just built. Note that the subtree
- -- substitution is performed with Rewrite so as to be
- -- able to retrieve the original aggregate.
- --
- -- The aggregate subtree manipulation performed by Resolve_Record_Aggregate
- -- yields the aggregate format expected by Gigi. Typically, this kind of
- -- tree manipulations are done in the expander. However, because the
- -- semantic checks that need to be performed on record aggregates really
- -- go hand in hand with the record aggreagate normalization, the aggregate
- -- subtree transformation is performed during resolution rather than
- -- expansion. Had we decided otherwise we would have had to duplicate
- -- most of the code in the expansion procedure Expand_Record_Aggregate.
- -- Note, however, that all the expansion concerning aggegates for tagged
- -- records is done in Expand_Record_Aggregate.
- --
- -- The algorithm of Resolve_Record_Aggregate proceeds as follows:
- --
- -- 1. Make sure that the record type against which the record aggregate
- -- has to be resolved is not abstract. Furthermore if the type is
- -- a null aggregate make sure the input aggregate N is also null.
- --
- -- 2. Verify that the structure of the aggregate is that of a record
- -- aggregate. Specifically, look for component associations and ensure
- -- that each choice list only has identifiers or the N_Others_Choice
- -- node. Also make sure that if present, the N_Others_Choice occurs
- -- last and by itself.
- --
- -- 3. If Typ contains discriminants, the values for each discriminant
- -- is looked for. If the record type Typ has variants, we check
- -- that the expressions corresponding to each discriminant ruling
- -- the (possibly nested) variant parts of Typ, are static. This
- -- allows us to determine the variant parts to which the rest of
- -- the aggregate must conform. The names of discriminants with their
- -- values are saved in a new association list, New_Assoc_List which
- -- is later augmented with the names and values of the remaining
- -- components in the record type.
- --
- -- During this phase we also make sure that every discriminant is
- -- assigned exactly one value. Note that when several values
- -- for a given discriminant are found, semantic processing continues
- -- looking for further errors. In this case it's the first
- -- discriminant value found which we will be recorded.
- --
- -- IMPORTANT NOTE: For derived tagged types this procedure expects
- -- First_Discriminant and Next_Discriminant to give the correct list
- -- of discriminants, in the correct order.
- --
- -- 4. After all the discriminant values have been gathered, we can
- -- set the Etype of the record aggregate. If Typ contains no
- -- discriminants this is straightforward: the Etype of N is just
- -- Typ, otherwise a new implicit constrained subtype of Typ is
- -- built to be the Etype of N.
- --
- -- 5. Gather the remaining record components according to the discriminant
- -- values. This involves recursively traversing the record type
- -- structure to see what variants are selected by the given discriminant
- -- values. This processing is a little more convoluted if Typ is a
- -- derived tagged types since we need to retrieve the record structure
- -- of all the ancestors of Typ.
- --
- -- 6. After gathering the record components we look for their values
- -- in the record aggregate and emit appropriate error messages
- -- should we not find such values or should they be duplicated.
- --
- -- 7. We then make sure no illegal component names appear in the
- -- record aggegate and make sure that the type of the record
- -- components appearing in a same choice list is the same.
- -- Finally we ensure that the others choice, if present, is
- -- used to provide the value of at least a record component.
- --
- -- 8. The original aggregate node is replaced with the new named
- -- aggregate built in steps 3 through 6, as explained earlier.
- --
- -- Given the complexity of record aggregate resolution, the primary
- -- goal of this routine is clarity and simplicity rather than execution
- -- and storage efficiency. If there are only positional components in the
- -- aggregate the running time is linear. If there are associations
- -- the running time is still linear as long as the order of the
- -- associations is not too far off the order of the components in the
- -- record type. If this is not the case the running time is at worst
- -- quadratic in the size of the association list.
-
- procedure Check_Misspelled_Component
- (Elements : Elist_Id;
- Component : Node_Id);
- -- Give possible misspelling diagnostic if Component is likely to be
- -- a misspelling of one of the components of the Assoc_List.
- -- This is called by Resolv_Aggr_Expr after producing
- -- an invalid component error message.
-
- procedure Check_Static_Discriminated_Subtype (T : Entity_Id; V : Node_Id);
- -- An optimization: determine whether a discriminated subtype has a
- -- static constraint, and contains array components whose length is also
- -- static, either because they are constrained by the discriminant, or
- -- because the original component bounds are static.
-
- -----------------------------------------------------
- -- Subprograms used for ARRAY AGGREGATE Processing --
- -----------------------------------------------------
-
- function Resolve_Array_Aggregate
- (N : Node_Id;
- Index : Node_Id;
- Index_Constr : Node_Id;
- Component_Typ : Entity_Id;
- Others_Allowed : Boolean)
- return Boolean;
- -- This procedure performs the semantic checks for an array aggregate.
- -- True is returned if the aggregate resolution succeeds.
- -- The procedure works by recursively checking each nested aggregate.
- -- Specifically, after checking a sub-aggreate nested at the i-th level
- -- we recursively check all the subaggregates at the i+1-st level (if any).
- -- Note that for aggregates analysis and resolution go hand in hand.
- -- Aggregate analysis has been delayed up to here and it is done while
- -- resolving the aggregate.
- --
- -- N is the current N_Aggregate node to be checked.
- --
- -- Index is the index node corresponding to the array sub-aggregate that
- -- we are currently checking (RM 4.3.3 (8)). Its Etype is the
- -- corresponding index type (or subtype).
- --
- -- Index_Constr is the node giving the applicable index constraint if
- -- any (RM 4.3.3 (10)). It "is a constraint provided by certain
- -- contexts [...] that can be used to determine the bounds of the array
- -- value specified by the aggregate". If Others_Allowed below is False
- -- there is no applicable index constraint and this node is set to Index.
- --
- -- Component_Typ is the array component type.
- --
- -- Others_Allowed indicates whether an others choice is allowed
- -- in the context where the top-level aggregate appeared.
- --
- -- The algorithm of Resolve_Array_Aggregate proceeds as follows:
- --
- -- 1. Make sure that the others choice, if present, is by itself and
- -- appears last in the sub-aggregate. Check that we do not have
- -- positional and named components in the array sub-aggregate (unless
- -- the named association is an others choice). Finally if an others
- -- choice is present, make sure it is allowed in the aggregate contex.
- --
- -- 2. If the array sub-aggregate contains discrete_choices:
- --
- -- (A) Verify their validity. Specifically verify that:
- --
- -- (a) If a null range is present it must be the only possible
- -- choice in the array aggregate.
- --
- -- (b) Ditto for a non static range.
- --
- -- (c) Ditto for a non static expression.
- --
- -- In addition this step analyzes and resolves each discrete_choice,
- -- making sure that its type is the type of the corresponding Index.
- -- If we are not at the lowest array aggregate level (in the case of
- -- multi-dimensional aggregates) then invoke Resolve_Array_Aggregate
- -- recursively on each component expression. Otherwise, resolve the
- -- bottom level component expressions against the expected component
- -- type ONLY IF the component corresponds to a single discrete choice
- -- which is not an others choice (to see why read the DELAYED
- -- COMPONENT RESOLUTION below).
- --
- -- (B) Determine the bounds of the sub-aggregate and lowest and
- -- highest choice values.
- --
- -- 3. For positional aggregates:
- --
- -- (A) Loop over the component expressions either recursively invoking
- -- Resolve_Array_Aggregate on each of these for multi-dimensional
- -- array aggregates or resolving the bottom level component
- -- expressions against the expected component type.
- --
- -- (B) Determine the bounds of the positional sub-aggregates.
- --
- -- 4. Try to determine statically whether the evaluation of the array
- -- sub-aggregate raises Constraint_Error. If yes emit proper
- -- warnings. The precise checks are the following:
- --
- -- (A) Check that the index range defined by aggregate bounds is
- -- compatible with corresponding index subtype.
- -- We also check against the base type. In fact it could be that
- -- Low/High bounds of the base type are static whereas those of
- -- the index subtype are not. Thus if we can statically catch
- -- a problem with respect to the base type we are guaranteed
- -- that the same problem will arise with the index subtype
- --
- -- (B) If we are dealing with a named aggregate containing an others
- -- choice and at least one discrete choice then make sure the range
- -- specified by the discrete choices does not overflow the
- -- aggregate bounds. We also check against the index type and base
- -- type bounds for the same reasons given in (A).
- --
- -- (C) If we are dealing with a positional aggregate with an others
- -- choice make sure the number of positional elements specified
- -- does not overflow the aggregate bounds. We also check against
- -- the index type and base type bounds as mentioned in (A).
- --
- -- Finally construct an N_Range node giving the sub-aggregate bounds.
- -- Set the Aggregate_Bounds field of the sub-aggregate to be this
- -- N_Range. The routine Array_Aggr_Subtype below uses such N_Ranges
- -- to build the appropriate aggregate subtype. Aggregate_Bounds
- -- information is needed during expansion.
- --
- -- DELAYED COMPONENT RESOLUTION: The resolution of bottom level component
- -- expressions in an array aggregate may call Duplicate_Subexpr or some
- -- other routine that inserts code just outside the outermost aggregate.
- -- If the array aggregate contains discrete choices or an others choice,
- -- this may be wrong. Consider for instance the following example.
- --
- -- type Rec is record
- -- V : Integer := 0;
- -- end record;
- --
- -- type Acc_Rec is access Rec;
- -- Arr : array (1..3) of Acc_Rec := (1 .. 3 => new Rec);
- --
- -- Then the transformation of "new Rec" that occurs during resolution
- -- entails the following code modifications
- --
- -- P7b : constant Acc_Rec := new Rec;
- -- Rec_init_proc (P7b.all);
- -- Arr : array (1..3) of Acc_Rec := (1 .. 3 => P7b);
- --
- -- This code transformation is clearly wrong, since we need to call
- -- "new Rec" for each of the 3 array elements. To avoid this problem we
- -- delay resolution of the components of non positional array aggregates
- -- to the expansion phase. As an optimization, if the discrete choice
- -- specifies a single value we do not delay resolution.
-
- function Array_Aggr_Subtype (N : Node_Id; Typ : Node_Id) return Entity_Id;
- -- This routine returns the type or subtype of an array aggregate.
- --
- -- N is the array aggregate node whose type we return.
- --
- -- Typ is the context type in which N occurs.
- --
- -- This routine creates an implicit array subtype whose bouds are
- -- those defined by the aggregate. When this routine is invoked
- -- Resolve_Array_Aggregate has already processed aggregate N. Thus the
- -- Aggregate_Bounds of each sub-aggregate, is an N_Range node giving the
- -- sub-aggregate bounds. When building the aggegate itype, this function
- -- traverses the array aggregate N collecting such Aggregate_Bounds and
- -- constructs the proper array aggregate itype.
- --
- -- Note that in the case of multidimensional aggregates each inner
- -- sub-aggregate corresponding to a given array dimension, may provide a
- -- different bounds. If it is possible to determine statically that
- -- some sub-aggregates corresponding to the same index do not have the
- -- same bounds, then a warning is emitted. If such check is not possible
- -- statically (because some sub-aggregate bounds are dynamic expressions)
- -- then this job is left to the expander. In all cases the particular
- -- bounds that this function will chose for a given dimension is the first
- -- N_Range node for a sub-aggregate corresponding to that dimension.
- --
- -- Note that the Raises_Constraint_Error flag of an array aggregate
- -- whose evaluation is determined to raise CE by Resolve_Array_Aggregate,
- -- is set in Resolve_Array_Aggregate but the aggregate is not
- -- immediately replaced with a raise CE. In fact, Array_Aggr_Subtype must
- -- first construct the proper itype for the aggregate (Gigi needs
- -- this). After constructing the proper itype we will eventually replace
- -- the top-level aggregate with a raise CE (done in Resolve_Aggregate).
- -- Of course in cases such as:
- --
- -- type Arr is array (integer range <>) of Integer;
- -- A : Arr := (positive range -1 .. 2 => 0);
- --
- -- The bounds of the aggregate itype are cooked up to look reasonable
- -- (in this particular case the bounds will be 1 .. 2).
-
- procedure Aggregate_Constraint_Checks
- (Exp : Node_Id;
- Check_Typ : Entity_Id);
- -- Checks expression Exp against subtype Check_Typ. If Exp is an
- -- aggregate and Check_Typ a constrained record type with discriminants,
- -- we generate the appropriate discriminant checks. If Exp is an array
- -- aggregate then emit the appropriate length checks. If Exp is a scalar
- -- type, or a string literal, Exp is changed into Check_Typ'(Exp) to
- -- ensure that range checks are performed at run time.
-
- procedure Make_String_Into_Aggregate (N : Node_Id);
- -- A string literal can appear in a context in which a one dimensional
- -- array of characters is expected. This procedure simply rewrites the
- -- string as an aggregate, prior to resolution.
-
- ---------------------------------
- -- Aggregate_Constraint_Checks --
- ---------------------------------
-
- procedure Aggregate_Constraint_Checks
- (Exp : Node_Id;
- Check_Typ : Entity_Id)
- is
- Exp_Typ : constant Entity_Id := Etype (Exp);
-
- begin
- if Raises_Constraint_Error (Exp) then
- return;
- end if;
-
- -- This is really expansion activity, so make sure that expansion
- -- is on and is allowed.
-
- if not Expander_Active or else In_Default_Expression then
- return;
- end if;
-
- -- First check if we have to insert discriminant checks
-
- if Has_Discriminants (Exp_Typ) then
- Apply_Discriminant_Check (Exp, Check_Typ);
-
- -- Next emit length checks for array aggregates
-
- elsif Is_Array_Type (Exp_Typ) then
- Apply_Length_Check (Exp, Check_Typ);
-
- -- Finally emit scalar and string checks. If we are dealing with a
- -- scalar literal we need to check by hand because the Etype of
- -- literals is not necessarily correct.
-
- elsif Is_Scalar_Type (Exp_Typ)
- and then Compile_Time_Known_Value (Exp)
- then
- if Is_Out_Of_Range (Exp, Base_Type (Check_Typ)) then
- Apply_Compile_Time_Constraint_Error
- (Exp, "value not in range of}?",
- Ent => Base_Type (Check_Typ),
- Typ => Base_Type (Check_Typ));
-
- elsif Is_Out_Of_Range (Exp, Check_Typ) then
- Apply_Compile_Time_Constraint_Error
- (Exp, "value not in range of}?",
- Ent => Check_Typ,
- Typ => Check_Typ);
-
- elsif not Range_Checks_Suppressed (Check_Typ) then
- Apply_Scalar_Range_Check (Exp, Check_Typ);
- end if;
-
- elsif (Is_Scalar_Type (Exp_Typ)
- or else Nkind (Exp) = N_String_Literal)
- and then Exp_Typ /= Check_Typ
- then
- if Is_Entity_Name (Exp)
- and then Ekind (Entity (Exp)) = E_Constant
- then
- -- If expression is a constant, it is worthwhile checking whether
- -- it is a bound of the type.
-
- if (Is_Entity_Name (Type_Low_Bound (Check_Typ))
- and then Entity (Exp) = Entity (Type_Low_Bound (Check_Typ)))
- or else (Is_Entity_Name (Type_High_Bound (Check_Typ))
- and then Entity (Exp) = Entity (Type_High_Bound (Check_Typ)))
- then
- return;
-
- else
- Rewrite (Exp, Convert_To (Check_Typ, Relocate_Node (Exp)));
- Analyze_And_Resolve (Exp, Check_Typ);
- end if;
- else
- Rewrite (Exp, Convert_To (Check_Typ, Relocate_Node (Exp)));
- Analyze_And_Resolve (Exp, Check_Typ);
- end if;
-
- end if;
- end Aggregate_Constraint_Checks;
-
- ------------------------
- -- Array_Aggr_Subtype --
- ------------------------
-
- function Array_Aggr_Subtype
- (N : Node_Id;
- Typ : Entity_Id)
- return Entity_Id
- is
- Aggr_Dimension : constant Pos := Number_Dimensions (Typ);
- -- Number of aggregate index dimensions.
-
- Aggr_Range : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
- -- Constrained N_Range of each index dimension in our aggregate itype.
-
- Aggr_Low : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
- Aggr_High : array (1 .. Aggr_Dimension) of Node_Id := (others => Empty);
- -- Low and High bounds for each index dimension in our aggregate itype.
-
- Is_Fully_Positional : Boolean := True;
-
- procedure Collect_Aggr_Bounds (N : Node_Id; Dim : Pos);
- -- N is an array (sub-)aggregate. Dim is the dimension corresponding to
- -- (sub-)aggregate N. This procedure collects the constrained N_Range
- -- nodes corresponding to each index dimension of our aggregate itype.
- -- These N_Range nodes are collected in Aggr_Range above.
- -- Likewise collect in Aggr_Low & Aggr_High above the low and high
- -- bounds of each index dimension. If, when collecting, two bounds
- -- corresponding to the same dimension are static and found to differ,
- -- then emit a warning, and mark N as raising Constraint_Error.
-
- -------------------------
- -- Collect_Aggr_Bounds --
- -------------------------
-
- procedure Collect_Aggr_Bounds (N : Node_Id; Dim : Pos) is
- This_Range : constant Node_Id := Aggregate_Bounds (N);
- -- The aggregate range node of this specific sub-aggregate.
-
- This_Low : constant Node_Id := Low_Bound (Aggregate_Bounds (N));
- This_High : constant Node_Id := High_Bound (Aggregate_Bounds (N));
- -- The aggregate bounds of this specific sub-aggregate.
-
- Assoc : Node_Id;
- Expr : Node_Id;
-
- begin
- -- Collect the first N_Range for a given dimension that you find.
- -- For a given dimension they must be all equal anyway.
-
- if No (Aggr_Range (Dim)) then
- Aggr_Low (Dim) := This_Low;
- Aggr_High (Dim) := This_High;
- Aggr_Range (Dim) := This_Range;
-
- else
- if Compile_Time_Known_Value (This_Low) then
- if not Compile_Time_Known_Value (Aggr_Low (Dim)) then
- Aggr_Low (Dim) := This_Low;
-
- elsif Expr_Value (This_Low) /= Expr_Value (Aggr_Low (Dim)) then
- Set_Raises_Constraint_Error (N);
- Error_Msg_N ("Sub-aggregate low bound mismatch?", N);
- Error_Msg_N ("Constraint_Error will be raised at run-time?",
- N);
- end if;
- end if;
-
- if Compile_Time_Known_Value (This_High) then
- if not Compile_Time_Known_Value (Aggr_High (Dim)) then
- Aggr_High (Dim) := This_High;
-
- elsif
- Expr_Value (This_High) /= Expr_Value (Aggr_High (Dim))
- then
- Set_Raises_Constraint_Error (N);
- Error_Msg_N ("Sub-aggregate high bound mismatch?", N);
- Error_Msg_N ("Constraint_Error will be raised at run-time?",
- N);
- end if;
- end if;
- end if;
-
- if Dim < Aggr_Dimension then
-
- -- Process positional components
-
- if Present (Expressions (N)) then
- Expr := First (Expressions (N));
- while Present (Expr) loop
- Collect_Aggr_Bounds (Expr, Dim + 1);
- Next (Expr);
- end loop;
- end if;
-
- -- Process component associations
-
- if Present (Component_Associations (N)) then
- Is_Fully_Positional := False;
-
- Assoc := First (Component_Associations (N));
- while Present (Assoc) loop
- Expr := Expression (Assoc);
- Collect_Aggr_Bounds (Expr, Dim + 1);
- Next (Assoc);
- end loop;
- end if;
- end if;
- end Collect_Aggr_Bounds;
-
- -- Array_Aggr_Subtype variables
-
- Itype : Entity_Id;
- -- the final itype of the overall aggregate
-
- Index_Constraints : List_Id := New_List;
- -- The list of index constraints of the aggregate itype.
-
- -- Start of processing for Array_Aggr_Subtype
-
- begin
- -- Make sure that the list of index constraints is properly attached
- -- to the tree, and then collect the aggregate bounds.
-
- Set_Parent (Index_Constraints, N);
- Collect_Aggr_Bounds (N, 1);
-
- -- Build the list of constrained indices of our aggregate itype.
-
- for J in 1 .. Aggr_Dimension loop
- Create_Index : declare
- Index_Base : Entity_Id := Base_Type (Etype (Aggr_Range (J)));
- Index_Typ : Entity_Id;
-
- begin
- -- Construct the Index subtype
-
- Index_Typ := Create_Itype (Subtype_Kind (Ekind (Index_Base)), N);
-
- Set_Etype (Index_Typ, Index_Base);
-
- if Is_Character_Type (Index_Base) then
- Set_Is_Character_Type (Index_Typ);
- end if;
-
- Set_Size_Info (Index_Typ, (Index_Base));
- Set_RM_Size (Index_Typ, RM_Size (Index_Base));
- Set_First_Rep_Item (Index_Typ, First_Rep_Item (Index_Base));
- Set_Scalar_Range (Index_Typ, Aggr_Range (J));
-
- if Is_Discrete_Or_Fixed_Point_Type (Index_Typ) then
- Set_RM_Size (Index_Typ, UI_From_Int (Minimum_Size (Index_Typ)));
- end if;
-
- Set_Etype (Aggr_Range (J), Index_Typ);
-
- Append (Aggr_Range (J), To => Index_Constraints);
- end Create_Index;
- end loop;
-
- -- Now build the Itype
-
- Itype := Create_Itype (E_Array_Subtype, N);
-
- Set_First_Rep_Item (Itype, First_Rep_Item (Typ));
- Set_Component_Type (Itype, Component_Type (Typ));
- Set_Convention (Itype, Convention (Typ));
- Set_Depends_On_Private (Itype, Has_Private_Component (Typ));
- Set_Etype (Itype, Base_Type (Typ));
- Set_Has_Alignment_Clause (Itype, Has_Alignment_Clause (Typ));
- Set_Is_Aliased (Itype, Is_Aliased (Typ));
- Set_Suppress_Index_Checks (Itype, Suppress_Index_Checks (Typ));
- Set_Suppress_Length_Checks (Itype, Suppress_Length_Checks (Typ));
- Set_Depends_On_Private (Itype, Depends_On_Private (Typ));
-
- Set_First_Index (Itype, First (Index_Constraints));
- Set_Is_Constrained (Itype, True);
- Set_Is_Internal (Itype, True);
- Init_Size_Align (Itype);
-
- -- A simple optimization: purely positional aggregates of static
- -- components should be passed to gigi unexpanded whenever possible,
- -- and regardless of the staticness of the bounds themselves. Subse-
- -- quent checks in exp_aggr verify that type is not packed, etc.
-
- Set_Size_Known_At_Compile_Time (Itype,
- Is_Fully_Positional
- and then Comes_From_Source (N)
- and then Size_Known_At_Compile_Time (Component_Type (Typ)));
-
- -- We always need a freeze node for a packed array subtype, so that
- -- we can build the Packed_Array_Type corresponding to the subtype.
- -- If expansion is disabled, the packed array subtype is not built,
- -- and we must not generate a freeze node for the type, or else it
- -- will appear incomplete to gigi.
-
- if Is_Packed (Itype) and then not In_Default_Expression
- and then Expander_Active
- then
- Freeze_Itype (Itype, N);
- end if;
-
- return Itype;
- end Array_Aggr_Subtype;
-
- --------------------------------
- -- Check_Misspelled_Component --
- --------------------------------
-
- procedure Check_Misspelled_Component
- (Elements : Elist_Id;
- Component : Node_Id)
- is
- Max_Suggestions : constant := 2;
-
- Nr_Of_Suggestions : Natural := 0;
- Suggestion_1 : Entity_Id := Empty;
- Suggestion_2 : Entity_Id := Empty;
- Component_Elmt : Elmt_Id;
-
- begin
- -- All the components of List are matched against Component and
- -- a count is maintained of possible misspellings. When at the
- -- end of the analysis there are one or two (not more!) possible
- -- misspellings, these misspellings will be suggested as
- -- possible correction.
-
- Get_Name_String (Chars (Component));
-
- declare
- S : constant String (1 .. Name_Len) :=
- Name_Buffer (1 .. Name_Len);
-
- begin
-
- Component_Elmt := First_Elmt (Elements);
-
- while Nr_Of_Suggestions <= Max_Suggestions
- and then Present (Component_Elmt)
- loop
-
- Get_Name_String (Chars (Node (Component_Elmt)));
-
- if Is_Bad_Spelling_Of (Name_Buffer (1 .. Name_Len), S) then
- Nr_Of_Suggestions := Nr_Of_Suggestions + 1;
-
- case Nr_Of_Suggestions is
- when 1 => Suggestion_1 := Node (Component_Elmt);
- when 2 => Suggestion_2 := Node (Component_Elmt);
- when others => exit;
- end case;
- end if;
-
- Next_Elmt (Component_Elmt);
- end loop;
-
- -- Report at most two suggestions
-
- if Nr_Of_Suggestions = 1 then
- Error_Msg_NE ("\possible misspelling of&",
- Component, Suggestion_1);
-
- elsif Nr_Of_Suggestions = 2 then
- Error_Msg_Node_2 := Suggestion_2;
- Error_Msg_NE ("\possible misspelling of& or&",
- Component, Suggestion_1);
- end if;
- end;
- end Check_Misspelled_Component;
-
- ----------------------------------------
- -- Check_Static_Discriminated_Subtype --
- ----------------------------------------
-
- procedure Check_Static_Discriminated_Subtype (T : Entity_Id; V : Node_Id) is
- Disc : constant Entity_Id := First_Discriminant (T);
- Comp : Entity_Id;
- Ind : Entity_Id;
-
- begin
- if Has_Record_Rep_Clause (Base_Type (T)) then
- return;
-
- elsif Present (Next_Discriminant (Disc)) then
- return;
-
- elsif Nkind (V) /= N_Integer_Literal then
- return;
- end if;
-
- Comp := First_Component (T);
-
- while Present (Comp) loop
-
- if Is_Scalar_Type (Etype (Comp)) then
- null;
-
- elsif Is_Private_Type (Etype (Comp))
- and then Present (Full_View (Etype (Comp)))
- and then Is_Scalar_Type (Full_View (Etype (Comp)))
- then
- null;
-
- elsif Is_Array_Type (Etype (Comp)) then
-
- if Is_Bit_Packed_Array (Etype (Comp)) then
- return;
- end if;
-
- Ind := First_Index (Etype (Comp));
-
- while Present (Ind) loop
-
- if Nkind (Ind) /= N_Range
- or else Nkind (Low_Bound (Ind)) /= N_Integer_Literal
- or else Nkind (High_Bound (Ind)) /= N_Integer_Literal
- then
- return;
- end if;
-
- Next_Index (Ind);
- end loop;
-
- else
- return;
- end if;
-
- Next_Component (Comp);
- end loop;
-
- -- On exit, all components have statically known sizes.
-
- Set_Size_Known_At_Compile_Time (T);
- end Check_Static_Discriminated_Subtype;
-
- --------------------------------
- -- Make_String_Into_Aggregate --
- --------------------------------
-
- procedure Make_String_Into_Aggregate (N : Node_Id) is
- C : Char_Code;
- C_Node : Node_Id;
- Exprs : List_Id := New_List;
- Loc : constant Source_Ptr := Sloc (N);
- New_N : Node_Id;
- P : Source_Ptr := Loc + 1;
- Str : constant String_Id := Strval (N);
- Strlen : constant Nat := String_Length (Str);
-
- begin
- for J in 1 .. Strlen loop
- C := Get_String_Char (Str, J);
- Set_Character_Literal_Name (C);
-
- C_Node := Make_Character_Literal (P, Name_Find, C);
- Set_Etype (C_Node, Any_Character);
- Set_Analyzed (C_Node);
- Append_To (Exprs, C_Node);
-
- P := P + 1;
- -- something special for wide strings ?
- end loop;
-
- New_N := Make_Aggregate (Loc, Expressions => Exprs);
- Set_Analyzed (New_N);
- Set_Etype (New_N, Any_Composite);
-
- Rewrite (N, New_N);
- end Make_String_Into_Aggregate;
-
- -----------------------
- -- Resolve_Aggregate --
- -----------------------
-
- procedure Resolve_Aggregate (N : Node_Id; Typ : Entity_Id) is
- Pkind : constant Node_Kind := Nkind (Parent (N));
-
- Aggr_Subtyp : Entity_Id;
- -- The actual aggregate subtype. This is not necessarily the same as Typ
- -- which is the subtype of the context in which the aggregate was found.
-
- begin
- if Is_Limited_Type (Typ) then
- Error_Msg_N ("aggregate type cannot be limited", N);
-
- elsif Is_Limited_Composite (Typ) then
- Error_Msg_N ("aggregate type cannot have limited component", N);
-
- elsif Is_Class_Wide_Type (Typ) then
- Error_Msg_N ("type of aggregate cannot be class-wide", N);
-
- elsif Typ = Any_String
- or else Typ = Any_Composite
- then
- Error_Msg_N ("no unique type for aggregate", N);
- Set_Etype (N, Any_Composite);
-
- elsif Is_Array_Type (Typ) and then Null_Record_Present (N) then
- Error_Msg_N ("null record forbidden in array aggregate", N);
-
- elsif Is_Record_Type (Typ) then
- Resolve_Record_Aggregate (N, Typ);
-
- elsif Is_Array_Type (Typ) then
-
- -- First a special test, for the case of a positional aggregate
- -- of characters which can be replaced by a string literal.
- -- Do not perform this transformation if this was a string literal
- -- to start with, whose components needed constraint checks, or if
- -- the component type is non-static, because it will require those
- -- checks and be transformed back into an aggregate.
-
- if Number_Dimensions (Typ) = 1
- and then
- (Root_Type (Component_Type (Typ)) = Standard_Character
- or else
- Root_Type (Component_Type (Typ)) = Standard_Wide_Character)
- and then No (Component_Associations (N))
- and then not Is_Limited_Composite (Typ)
- and then not Is_Private_Composite (Typ)
- and then not Is_Bit_Packed_Array (Typ)
- and then Nkind (Original_Node (Parent (N))) /= N_String_Literal
- and then Is_Static_Subtype (Component_Type (Typ))
- then
- declare
- Expr : Node_Id;
-
- begin
- Expr := First (Expressions (N));
- while Present (Expr) loop
- exit when Nkind (Expr) /= N_Character_Literal;
- Next (Expr);
- end loop;
-
- if No (Expr) then
- Start_String;
-
- Expr := First (Expressions (N));
- while Present (Expr) loop
- Store_String_Char (Char_Literal_Value (Expr));
- Next (Expr);
- end loop;
-
- Rewrite (N,
- Make_String_Literal (Sloc (N), End_String));
-
- Analyze_And_Resolve (N, Typ);
- return;
- end if;
- end;
- end if;
-
- -- Here if we have a real aggregate to deal with
-
- Array_Aggregate : declare
- Aggr_Resolved : Boolean;
- Aggr_Typ : Entity_Id := Etype (Typ);
- -- This is the unconstrained array type, which is the type
- -- against which the aggregate is to be resoved. Typ itself
- -- is the array type of the context which may not be the same
- -- subtype as the subtype for the final aggregate.
-
- begin
- -- In the following we determine whether an others choice is
- -- allowed inside the array aggregate. The test checks the context
- -- in which the array aggregate occurs. If the context does not
- -- permit it, or the aggregate type is unconstrained, an others
- -- choice is not allowed.
- --
- -- Note that there is no node for Explicit_Actual_Parameter.
- -- To test for this context we therefore have to test for node
- -- N_Parameter_Association which itself appears only if there is a
- -- formal parameter. Consequently we also need to test for
- -- N_Procedure_Call_Statement or N_Function_Call.
-
- if Is_Constrained (Typ) and then
- (Pkind = N_Assignment_Statement or else
- Pkind = N_Parameter_Association or else
- Pkind = N_Function_Call or else
- Pkind = N_Procedure_Call_Statement or else
- Pkind = N_Generic_Association or else
- Pkind = N_Formal_Object_Declaration or else
- Pkind = N_Return_Statement or else
- Pkind = N_Object_Declaration or else
- Pkind = N_Component_Declaration or else
- Pkind = N_Parameter_Specification or else
- Pkind = N_Qualified_Expression or else
- Pkind = N_Aggregate or else
- Pkind = N_Extension_Aggregate or else
- Pkind = N_Component_Association)
- then
- Aggr_Resolved :=
- Resolve_Array_Aggregate
- (N,
- Index => First_Index (Aggr_Typ),
- Index_Constr => First_Index (Typ),
- Component_Typ => Component_Type (Typ),
- Others_Allowed => True);
-
- else
- Aggr_Resolved :=
- Resolve_Array_Aggregate
- (N,
- Index => First_Index (Aggr_Typ),
- Index_Constr => First_Index (Aggr_Typ),
- Component_Typ => Component_Type (Typ),
- Others_Allowed => False);
- end if;
-
- if not Aggr_Resolved then
- Aggr_Subtyp := Any_Composite;
- else
- Aggr_Subtyp := Array_Aggr_Subtype (N, Typ);
- end if;
-
- Set_Etype (N, Aggr_Subtyp);
- end Array_Aggregate;
-
- else
- Error_Msg_N ("illegal context for aggregate", N);
-
- end if;
-
- -- If we can determine statically that the evaluation of the
- -- aggregate raises Constraint_Error, then replace the
- -- aggregate with an N_Raise_Constraint_Error node, but set the
- -- Etype to the right aggregate subtype. Gigi needs this.
-
- if Raises_Constraint_Error (N) then
- Aggr_Subtyp := Etype (N);
- Rewrite (N, Make_Raise_Constraint_Error (Sloc (N)));
- Set_Raises_Constraint_Error (N);
- Set_Etype (N, Aggr_Subtyp);
- Set_Analyzed (N);
- end if;
-
- end Resolve_Aggregate;
-
- -----------------------------
- -- Resolve_Array_Aggregate --
- -----------------------------
-
- function Resolve_Array_Aggregate
- (N : Node_Id;
- Index : Node_Id;
- Index_Constr : Node_Id;
- Component_Typ : Entity_Id;
- Others_Allowed : Boolean)
- return Boolean
- is
- Loc : constant Source_Ptr := Sloc (N);
-
- Failure : constant Boolean := False;
- Success : constant Boolean := True;
-
- Index_Typ : constant Entity_Id := Etype (Index);
- Index_Typ_Low : constant Node_Id := Type_Low_Bound (Index_Typ);
- Index_Typ_High : constant Node_Id := Type_High_Bound (Index_Typ);
- -- The type of the index corresponding to the array sub-aggregate
- -- along with its low and upper bounds
-
- Index_Base : constant Entity_Id := Base_Type (Index_Typ);
- Index_Base_Low : constant Node_Id := Type_Low_Bound (Index_Base);
- Index_Base_High : constant Node_Id := Type_High_Bound (Index_Base);
- -- ditto for the base type
-
- function Add (Val : Uint; To : Node_Id) return Node_Id;
- -- Creates a new expression node where Val is added to expression To.
- -- Tries to constant fold whenever possible. To must be an already
- -- analyzed expression.
-
- procedure Check_Bound (BH : Node_Id; AH : in out Node_Id);
- -- Checks that AH (the upper bound of an array aggregate) is <= BH
- -- (the upper bound of the index base type). If the check fails a
- -- warning is emitted, the Raises_Constraint_Error Flag of N is set,
- -- and AH is replaced with a duplicate of BH.
-
- procedure Check_Bounds (L, H : Node_Id; AL, AH : Node_Id);
- -- Checks that range AL .. AH is compatible with range L .. H. Emits a
- -- warning if not and sets the Raises_Constraint_Error Flag in N.
-
- procedure Check_Length (L, H : Node_Id; Len : Uint);
- -- Checks that range L .. H contains at least Len elements. Emits a
- -- warning if not and sets the Raises_Constraint_Error Flag in N.
-
- function Dynamic_Or_Null_Range (L, H : Node_Id) return Boolean;
- -- Returns True if range L .. H is dynamic or null.
-
- procedure Get (Value : out Uint; From : Node_Id; OK : out Boolean);
- -- Given expression node From, this routine sets OK to False if it
- -- cannot statically evaluate From. Otherwise it stores this static
- -- value into Value.
-
- function Resolve_Aggr_Expr
- (Expr : Node_Id;
- Single_Elmt : Boolean)
- return Boolean;
- -- Resolves aggregate expression Expr. Returs False if resolution
- -- fails. If Single_Elmt is set to False, the expression Expr may be
- -- used to initialize several array aggregate elements (this can
- -- happen for discrete choices such as "L .. H => Expr" or the others
- -- choice). In this event we do not resolve Expr unless expansion is
- -- disabled. To know why, see the DELAYED COMPONENT RESOLUTION
- -- note above.
-
- ---------
- -- Add --
- ---------
-
- function Add (Val : Uint; To : Node_Id) return Node_Id is
- Expr_Pos : Node_Id;
- Expr : Node_Id;
- To_Pos : Node_Id;
-
- begin
- if Raises_Constraint_Error (To) then
- return To;
- end if;
-
- -- First test if we can do constant folding
-
- if Compile_Time_Known_Value (To)
- or else Nkind (To) = N_Integer_Literal
- then
- Expr_Pos := Make_Integer_Literal (Loc, Expr_Value (To) + Val);
- Set_Is_Static_Expression (Expr_Pos);
- Set_Etype (Expr_Pos, Etype (To));
- Set_Analyzed (Expr_Pos, Analyzed (To));
-
- if not Is_Enumeration_Type (Index_Typ) then
- Expr := Expr_Pos;
-
- -- If we are dealing with enumeration return
- -- Index_Typ'Val (Expr_Pos)
-
- else
- Expr :=
- Make_Attribute_Reference
- (Loc,
- Prefix => New_Reference_To (Index_Typ, Loc),
- Attribute_Name => Name_Val,
- Expressions => New_List (Expr_Pos));
- end if;
-
- return Expr;
- end if;
-
- -- If we are here no constant folding possible
-
- if not Is_Enumeration_Type (Index_Base) then
- Expr :=
- Make_Op_Add (Loc,
- Left_Opnd => Duplicate_Subexpr (To),
- Right_Opnd => Make_Integer_Literal (Loc, Val));
-
- -- If we are dealing with enumeration return
- -- Index_Typ'Val (Index_Typ'Pos (To) + Val)
-
- else
- To_Pos :=
- Make_Attribute_Reference
- (Loc,
- Prefix => New_Reference_To (Index_Typ, Loc),
- Attribute_Name => Name_Pos,
- Expressions => New_List (Duplicate_Subexpr (To)));
-
- Expr_Pos :=
- Make_Op_Add (Loc,
- Left_Opnd => To_Pos,
- Right_Opnd => Make_Integer_Literal (Loc, Val));
-
- Expr :=
- Make_Attribute_Reference
- (Loc,
- Prefix => New_Reference_To (Index_Typ, Loc),
- Attribute_Name => Name_Val,
- Expressions => New_List (Expr_Pos));
- end if;
-
- return Expr;
- end Add;
-
- -----------------
- -- Check_Bound --
- -----------------
-
- procedure Check_Bound (BH : Node_Id; AH : in out Node_Id) is
- Val_BH : Uint;
- Val_AH : Uint;
-
- OK_BH : Boolean;
- OK_AH : Boolean;
-
- begin
- Get (Value => Val_BH, From => BH, OK => OK_BH);
- Get (Value => Val_AH, From => AH, OK => OK_AH);
-
- if OK_BH and then OK_AH and then Val_BH < Val_AH then
- Set_Raises_Constraint_Error (N);
- Error_Msg_N ("upper bound out of range?", AH);
- Error_Msg_N ("Constraint_Error will be raised at run-time?", AH);
-
- -- You need to set AH to BH or else in the case of enumerations
- -- indices we will not be able to resolve the aggregate bounds.
-
- AH := Duplicate_Subexpr (BH);
- end if;
- end Check_Bound;
-
- ------------------
- -- Check_Bounds --
- ------------------
-
- procedure Check_Bounds (L, H : Node_Id; AL, AH : Node_Id) is
- Val_L : Uint;
- Val_H : Uint;
- Val_AL : Uint;
- Val_AH : Uint;
-
- OK_L : Boolean;
- OK_H : Boolean;
- OK_AL : Boolean;
- OK_AH : Boolean;
-
- begin
- if Raises_Constraint_Error (N)
- or else Dynamic_Or_Null_Range (AL, AH)
- then
- return;
- end if;
-
- Get (Value => Val_L, From => L, OK => OK_L);
- Get (Value => Val_H, From => H, OK => OK_H);
-
- Get (Value => Val_AL, From => AL, OK => OK_AL);
- Get (Value => Val_AH, From => AH, OK => OK_AH);
-
- if OK_L and then Val_L > Val_AL then
- Set_Raises_Constraint_Error (N);
- Error_Msg_N ("lower bound of aggregate out of range?", N);
- Error_Msg_N ("Constraint_Error will be raised at run-time?", N);
- end if;
-
- if OK_H and then Val_H < Val_AH then
- Set_Raises_Constraint_Error (N);
- Error_Msg_N ("upper bound of aggregate out of range?", N);
- Error_Msg_N ("Constraint_Error will be raised at run-time?", N);
- end if;
- end Check_Bounds;
-
- ------------------
- -- Check_Length --
- ------------------
-
- procedure Check_Length (L, H : Node_Id; Len : Uint) is
- Val_L : Uint;
- Val_H : Uint;
-
- OK_L : Boolean;
- OK_H : Boolean;
-
- Range_Len : Uint;
-
- begin
- if Raises_Constraint_Error (N) then
- return;
- end if;
-
- Get (Value => Val_L, From => L, OK => OK_L);
- Get (Value => Val_H, From => H, OK => OK_H);
-
- if not OK_L or else not OK_H then
- return;
- end if;
-
- -- If null range length is zero
-
- if Val_L > Val_H then
- Range_Len := Uint_0;
- else
- Range_Len := Val_H - Val_L + 1;
- end if;
-
- if Range_Len < Len then
- Set_Raises_Constraint_Error (N);
- Error_Msg_N ("Too many elements?", N);
- Error_Msg_N ("Constraint_Error will be raised at run-time?", N);
- end if;
- end Check_Length;
-
- ---------------------------
- -- Dynamic_Or_Null_Range --
- ---------------------------
-
- function Dynamic_Or_Null_Range (L, H : Node_Id) return Boolean is
- Val_L : Uint;
- Val_H : Uint;
-
- OK_L : Boolean;
- OK_H : Boolean;
-
- begin
- Get (Value => Val_L, From => L, OK => OK_L);
- Get (Value => Val_H, From => H, OK => OK_H);
-
- return not OK_L or else not OK_H
- or else not Is_OK_Static_Expression (L)
- or else not Is_OK_Static_Expression (H)
- or else Val_L > Val_H;
- end Dynamic_Or_Null_Range;
-
- ---------
- -- Get --
- ---------
-
- procedure Get (Value : out Uint; From : Node_Id; OK : out Boolean) is
- begin
- OK := True;
-
- if Compile_Time_Known_Value (From) then
- Value := Expr_Value (From);
-
- -- If expression From is something like Some_Type'Val (10) then
- -- Value = 10
-
- elsif Nkind (From) = N_Attribute_Reference
- and then Attribute_Name (From) = Name_Val
- and then Compile_Time_Known_Value (First (Expressions (From)))
- then
- Value := Expr_Value (First (Expressions (From)));
-
- else
- Value := Uint_0;
- OK := False;
- end if;
- end Get;
-
- -----------------------
- -- Resolve_Aggr_Expr --
- -----------------------
-
- function Resolve_Aggr_Expr
- (Expr : Node_Id;
- Single_Elmt : Boolean)
- return Boolean
- is
- Nxt_Ind : Node_Id := Next_Index (Index);
- Nxt_Ind_Constr : Node_Id := Next_Index (Index_Constr);
- -- Index is the current index corresponding to the expression.
-
- Resolution_OK : Boolean := True;
- -- Set to False if resolution of the expression failed.
-
- begin
- -- If the array type against which we are resolving the aggregate
- -- has several dimensions, the expressions nested inside the
- -- aggregate must be further aggregates (or strings).
-
- if Present (Nxt_Ind) then
- if Nkind (Expr) /= N_Aggregate then
-
- -- A string literal can appear where a one-dimensional array
- -- of characters is expected. If the literal looks like an
- -- operator, it is still an operator symbol, which will be
- -- transformed into a string when analyzed.
-
- if Is_Character_Type (Component_Typ)
- and then No (Next_Index (Nxt_Ind))
- and then (Nkind (Expr) = N_String_Literal
- or else Nkind (Expr) = N_Operator_Symbol)
- then
- -- A string literal used in a multidimensional array
- -- aggregate in place of the final one-dimensional
- -- aggregate must not be enclosed in parentheses.
-
- if Paren_Count (Expr) /= 0 then
- Error_Msg_N ("No parenthesis allowed here", Expr);
- end if;
-
- Make_String_Into_Aggregate (Expr);
-
- else
- Error_Msg_N ("nested array aggregate expected", Expr);
- return Failure;
- end if;
- end if;
-
- Resolution_OK := Resolve_Array_Aggregate
- (Expr, Nxt_Ind, Nxt_Ind_Constr, Component_Typ, Others_Allowed);
-
- -- Do not resolve the expressions of discrete or others choices
- -- unless the expression covers a single component, or the expander
- -- is inactive.
-
- elsif Single_Elmt
- or else not Expander_Active
- or else In_Default_Expression
- then
- Analyze_And_Resolve (Expr, Component_Typ);
- Check_Non_Static_Context (Expr);
- Aggregate_Constraint_Checks (Expr, Component_Typ);
- end if;
-
- if Raises_Constraint_Error (Expr)
- and then Nkind (Parent (Expr)) /= N_Component_Association
- then
- Set_Raises_Constraint_Error (N);
- end if;
-
- return Resolution_OK;
- end Resolve_Aggr_Expr;
-
- -- Variables local to Resolve_Array_Aggregate
-
- Assoc : Node_Id;
- Choice : Node_Id;
- Expr : Node_Id;
-
- Who_Cares : Node_Id;
-
- Aggr_Low : Node_Id := Empty;
- Aggr_High : Node_Id := Empty;
- -- The actual low and high bounds of this sub-aggegate
-
- Choices_Low : Node_Id := Empty;
- Choices_High : Node_Id := Empty;
- -- The lowest and highest discrete choices values for a named aggregate
-
- Nb_Elements : Uint := Uint_0;
- -- The number of elements in a positional aggegate
-
- Others_Present : Boolean := False;
-
- Nb_Choices : Nat := 0;
- -- Contains the overall number of named choices in this sub-aggregate
-
- Nb_Discrete_Choices : Nat := 0;
- -- The overall number of discrete choices (not counting others choice)
-
- Case_Table_Size : Nat;
- -- Contains the size of the case table needed to sort aggregate choices
-
- -- Start of processing for Resolve_Array_Aggregate
-
- begin
- -- STEP 1: make sure the aggregate is correctly formatted
-
- if Present (Component_Associations (N)) then
- Assoc := First (Component_Associations (N));
- while Present (Assoc) loop
- Choice := First (Choices (Assoc));
- while Present (Choice) loop
- if Nkind (Choice) = N_Others_Choice then
- Others_Present := True;
-
- if Choice /= First (Choices (Assoc))
- or else Present (Next (Choice))
- then
- Error_Msg_N
- ("OTHERS must appear alone in a choice list", Choice);
- return Failure;
- end if;
-
- if Present (Next (Assoc)) then
- Error_Msg_N
- ("OTHERS must appear last in an aggregate", Choice);
- return Failure;
- end if;
-
- if Ada_83
- and then Assoc /= First (Component_Associations (N))
- and then (Nkind (Parent (N)) = N_Assignment_Statement
- or else
- Nkind (Parent (N)) = N_Object_Declaration)
- then
- Error_Msg_N
- ("(Ada 83) illegal context for OTHERS choice", N);
- end if;
- end if;
-
- Nb_Choices := Nb_Choices + 1;
- Next (Choice);
- end loop;
-
- Next (Assoc);
- end loop;
- end if;
-
- -- At this point we know that the others choice, if present, is by
- -- itself and appears last in the aggregate. Check if we have mixed
- -- positional and discrete associations (other than the others choice).
-
- if Present (Expressions (N))
- and then (Nb_Choices > 1
- or else (Nb_Choices = 1 and then not Others_Present))
- then
- Error_Msg_N
- ("named association cannot follow positional association",
- First (Choices (First (Component_Associations (N)))));
- return Failure;
- end if;
-
- -- Test for the validity of an others choice if present
-
- if Others_Present and then not Others_Allowed then
- Error_Msg_N
- ("OTHERS choice not allowed here",
- First (Choices (First (Component_Associations (N)))));
- return Failure;
- end if;
-
- -- STEP 2: Process named components
-
- if No (Expressions (N)) then
-
- if Others_Present then
- Case_Table_Size := Nb_Choices - 1;
- else
- Case_Table_Size := Nb_Choices;
- end if;
-
- Step_2 : declare
- Low : Node_Id;
- High : Node_Id;
- -- Denote the lowest and highest values in an aggregate choice
-
- Hi_Val : Uint;
- Lo_Val : Uint;
- -- High end of one range and Low end of the next. Should be
- -- contiguous if there is no hole in the list of values.
-
- Missing_Values : Boolean;
- -- Set True if missing index values
-
- S_Low : Node_Id := Empty;
- S_High : Node_Id := Empty;
- -- if a choice in an aggregate is a subtype indication these
- -- denote the lowest and highest values of the subtype
-
- Table : Case_Table_Type (1 .. Case_Table_Size);
- -- Used to sort all the different choice values
-
- Single_Choice : Boolean;
- -- Set to true every time there is a single discrete choice in a
- -- discrete association
-
- Prev_Nb_Discrete_Choices : Nat;
- -- Used to keep track of the number of discrete choices
- -- in the current association.
-
- begin
- -- STEP 2 (A): Check discrete choices validity.
-
- Assoc := First (Component_Associations (N));
- while Present (Assoc) loop
-
- Prev_Nb_Discrete_Choices := Nb_Discrete_Choices;
- Choice := First (Choices (Assoc));
- loop
- Analyze (Choice);
-
- if Nkind (Choice) = N_Others_Choice then
- Single_Choice := False;
- exit;
-
- -- Test for subtype mark without constraint
-
- elsif Is_Entity_Name (Choice) and then
- Is_Type (Entity (Choice))
- then
- if Base_Type (Entity (Choice)) /= Index_Base then
- Error_Msg_N
- ("invalid subtype mark in aggregate choice",
- Choice);
- return Failure;
- end if;
-
- elsif Nkind (Choice) = N_Subtype_Indication then
- Resolve_Discrete_Subtype_Indication (Choice, Index_Base);
-
- -- Does the subtype indication evaluation raise CE ?
-
- Get_Index_Bounds (Subtype_Mark (Choice), S_Low, S_High);
- Get_Index_Bounds (Choice, Low, High);
- Check_Bounds (S_Low, S_High, Low, High);
-
- else -- Choice is a range or an expression
- Resolve (Choice, Index_Base);
- Check_Non_Static_Context (Choice);
-
- -- Do not range check a choice. This check is redundant
- -- since this test is already performed when we check
- -- that the bounds of the array aggregate are within
- -- range.
-
- Set_Do_Range_Check (Choice, False);
- end if;
-
- -- If we could not resolve the discrete choice stop here
-
- if Etype (Choice) = Any_Type then
- return Failure;
-
- -- If the discrete choice raises CE get its original bounds.
-
- elsif Nkind (Choice) = N_Raise_Constraint_Error then
- Set_Raises_Constraint_Error (N);
- Get_Index_Bounds (Original_Node (Choice), Low, High);
-
- -- Otherwise get its bounds as usual
-
- else
- Get_Index_Bounds (Choice, Low, High);
- end if;
-
- if (Dynamic_Or_Null_Range (Low, High)
- or else (Nkind (Choice) = N_Subtype_Indication
- and then
- Dynamic_Or_Null_Range (S_Low, S_High)))
- and then Nb_Choices /= 1
- then
- Error_Msg_N
- ("dynamic or empty choice in aggregate " &
- "must be the only choice", Choice);
- return Failure;
- end if;
-
- Nb_Discrete_Choices := Nb_Discrete_Choices + 1;
- Table (Nb_Discrete_Choices).Choice_Lo := Low;
- Table (Nb_Discrete_Choices).Choice_Hi := High;
-
- Next (Choice);
-
- if No (Choice) then
- -- Check if we have a single discrete choice and whether
- -- this discrete choice specifies a single value.
-
- Single_Choice :=
- (Nb_Discrete_Choices = Prev_Nb_Discrete_Choices + 1)
- and then (Low = High);
-
- exit;
- end if;
- end loop;
-
- if not
- Resolve_Aggr_Expr
- (Expression (Assoc), Single_Elmt => Single_Choice)
- then
- return Failure;
- end if;
-
- Next (Assoc);
- end loop;
-
- -- If aggregate contains more than one choice then these must be
- -- static. Sort them and check that they are contiguous
-
- if Nb_Discrete_Choices > 1 then
- Sort_Case_Table (Table);
- Missing_Values := False;
-
- Outer : for J in 1 .. Nb_Discrete_Choices - 1 loop
- if Expr_Value (Table (J).Choice_Hi) >=
- Expr_Value (Table (J + 1).Choice_Lo)
- then
- Error_Msg_N
- ("duplicate choice values in array aggregate",
- Table (J).Choice_Hi);
- return Failure;
-
- elsif not Others_Present then
-
- Hi_Val := Expr_Value (Table (J).Choice_Hi);
- Lo_Val := Expr_Value (Table (J + 1).Choice_Lo);
-
- -- If missing values, output error messages
-
- if Lo_Val - Hi_Val > 1 then
-
- -- Header message if not first missing value
-
- if not Missing_Values then
- Error_Msg_N
- ("missing index value(s) in array aggregate", N);
- Missing_Values := True;
- end if;
-
- -- Output values of missing indexes
-
- Lo_Val := Lo_Val - 1;
- Hi_Val := Hi_Val + 1;
-
- -- Enumeration type case
-
- if Is_Enumeration_Type (Index_Typ) then
- Error_Msg_Name_1 :=
- Chars
- (Get_Enum_Lit_From_Pos
- (Index_Typ, Hi_Val, Loc));
-
- if Lo_Val = Hi_Val then
- Error_Msg_N ("\ %", N);
- else
- Error_Msg_Name_2 :=
- Chars
- (Get_Enum_Lit_From_Pos
- (Index_Typ, Lo_Val, Loc));
- Error_Msg_N ("\ % .. %", N);
- end if;
-
- -- Integer types case
-
- else
- Error_Msg_Uint_1 := Hi_Val;
-
- if Lo_Val = Hi_Val then
- Error_Msg_N ("\ ^", N);
- else
- Error_Msg_Uint_2 := Lo_Val;
- Error_Msg_N ("\ ^ .. ^", N);
- end if;
- end if;
- end if;
- end if;
- end loop Outer;
-
- if Missing_Values then
- Set_Etype (N, Any_Composite);
- return Failure;
- end if;
- end if;
-
- -- STEP 2 (B): Compute aggregate bounds and min/max choices values
-
- if Nb_Discrete_Choices > 0 then
- Choices_Low := Table (1).Choice_Lo;
- Choices_High := Table (Nb_Discrete_Choices).Choice_Hi;
- end if;
-
- if Others_Present then
- Get_Index_Bounds (Index_Constr, Aggr_Low, Aggr_High);
-
- else
- Aggr_Low := Choices_Low;
- Aggr_High := Choices_High;
- end if;
- end Step_2;
-
- -- STEP 3: Process positional components
-
- else
- -- STEP 3 (A): Process positional elements
-
- Expr := First (Expressions (N));
- Nb_Elements := Uint_0;
- while Present (Expr) loop
- Nb_Elements := Nb_Elements + 1;
-
- if not Resolve_Aggr_Expr (Expr, Single_Elmt => True) then
- return Failure;
- end if;
-
- Next (Expr);
- end loop;
-
- if Others_Present then
- Assoc := Last (Component_Associations (N));
- if not Resolve_Aggr_Expr (Expression (Assoc),
- Single_Elmt => False)
- then
- return Failure;
- end if;
- end if;
-
- -- STEP 3 (B): Compute the aggregate bounds
-
- if Others_Present then
- Get_Index_Bounds (Index_Constr, Aggr_Low, Aggr_High);
-
- else
- if Others_Allowed then
- Get_Index_Bounds (Index_Constr, Aggr_Low, Who_Cares);
- else
- Aggr_Low := Index_Typ_Low;
- end if;
-
- Aggr_High := Add (Nb_Elements - 1, To => Aggr_Low);
- Check_Bound (Index_Base_High, Aggr_High);
- end if;
- end if;
-
- -- STEP 4: Perform static aggregate checks and save the bounds
-
- -- Check (A)
-
- Check_Bounds (Index_Typ_Low, Index_Typ_High, Aggr_Low, Aggr_High);
- Check_Bounds (Index_Base_Low, Index_Base_High, Aggr_Low, Aggr_High);
-
- -- Check (B)
-
- if Others_Present and then Nb_Discrete_Choices > 0 then
- Check_Bounds (Aggr_Low, Aggr_High, Choices_Low, Choices_High);
- Check_Bounds (Index_Typ_Low, Index_Typ_High,
- Choices_Low, Choices_High);
- Check_Bounds (Index_Base_Low, Index_Base_High,
- Choices_Low, Choices_High);
-
- -- Check (C)
-
- elsif Others_Present and then Nb_Elements > 0 then
- Check_Length (Aggr_Low, Aggr_High, Nb_Elements);
- Check_Length (Index_Typ_Low, Index_Typ_High, Nb_Elements);
- Check_Length (Index_Base_Low, Index_Base_High, Nb_Elements);
-
- end if;
-
- if Raises_Constraint_Error (Aggr_Low)
- or else Raises_Constraint_Error (Aggr_High)
- then
- Set_Raises_Constraint_Error (N);
- end if;
-
- Aggr_Low := Duplicate_Subexpr (Aggr_Low);
-
- -- Do not duplicate Aggr_High if Aggr_High = Aggr_Low + Nb_Elements
- -- since the addition node returned by Add is not yet analyzed. Attach
- -- to tree and analyze first. Reset analyzed flag to insure it will get
- -- analyzed when it is a literal bound whose type must be properly
- -- set.
-
- if Others_Present or else Nb_Discrete_Choices > 0 then
- Aggr_High := Duplicate_Subexpr (Aggr_High);
-
- if Etype (Aggr_High) = Universal_Integer then
- Set_Analyzed (Aggr_High, False);
- end if;
- end if;
-
- Set_Aggregate_Bounds
- (N, Make_Range (Loc, Low_Bound => Aggr_Low, High_Bound => Aggr_High));
-
- -- The bounds may contain expressions that must be inserted upwards.
- -- Attach them fully to the tree. After analysis, remove side effects
- -- from upper bound, if still needed.
-
- Set_Parent (Aggregate_Bounds (N), N);
- Analyze_And_Resolve (Aggregate_Bounds (N), Index_Typ);
-
- if not Others_Present and then Nb_Discrete_Choices = 0 then
- Set_High_Bound (Aggregate_Bounds (N),
- Duplicate_Subexpr (High_Bound (Aggregate_Bounds (N))));
- end if;
-
- return Success;
- end Resolve_Array_Aggregate;
-
- ---------------------------------
- -- Resolve_Extension_Aggregate --
- ---------------------------------
-
- -- There are two cases to consider:
-
- -- a) If the ancestor part is a type mark, the components needed are
- -- the difference between the components of the expected type and the
- -- components of the given type mark.
-
- -- b) If the ancestor part is an expression, it must be unambiguous,
- -- and once we have its type we can also compute the needed components
- -- as in the previous case. In both cases, if the ancestor type is not
- -- the immediate ancestor, we have to build this ancestor recursively.
-
- -- In both cases discriminants of the ancestor type do not play a
- -- role in the resolution of the needed components, because inherited
- -- discriminants cannot be used in a type extension. As a result we can
- -- compute independently the list of components of the ancestor type and
- -- of the expected type.
-
- procedure Resolve_Extension_Aggregate (N : Node_Id; Typ : Entity_Id) is
- A : constant Node_Id := Ancestor_Part (N);
- A_Type : Entity_Id;
- I : Interp_Index;
- It : Interp;
- Imm_Type : Entity_Id;
-
- function Valid_Ancestor_Type return Boolean;
- -- Verify that the type of the ancestor part is a non-private ancestor
- -- of the expected type.
-
- function Valid_Ancestor_Type return Boolean is
- Imm_Type : Entity_Id;
-
- begin
- Imm_Type := Base_Type (Typ);
- while Is_Derived_Type (Imm_Type)
- and then Etype (Imm_Type) /= Base_Type (A_Type)
- loop
- Imm_Type := Etype (Base_Type (Imm_Type));
- end loop;
-
- if Etype (Imm_Type) /= Base_Type (A_Type) then
- Error_Msg_NE ("expect ancestor type of &", A, Typ);
- return False;
- else
- return True;
- end if;
- end Valid_Ancestor_Type;
-
- -- Start of processing for Resolve_Extension_Aggregate
-
- begin
- Analyze (A);
-
- if not Is_Tagged_Type (Typ) then
- Error_Msg_N ("type of extension aggregate must be tagged", N);
- return;
-
- elsif Is_Limited_Type (Typ) then
- Error_Msg_N ("aggregate type cannot be limited", N);
- return;
-
- elsif Is_Class_Wide_Type (Typ) then
- Error_Msg_N ("aggregate cannot be of a class-wide type", N);
- return;
- end if;
-
- if Is_Entity_Name (A)
- and then Is_Type (Entity (A))
- then
- A_Type := Get_Full_View (Entity (A));
- Imm_Type := Base_Type (Typ);
-
- if Valid_Ancestor_Type then
- Set_Entity (A, A_Type);
- Set_Etype (A, A_Type);
-
- Validate_Ancestor_Part (N);
- Resolve_Record_Aggregate (N, Typ);
- end if;
-
- elsif Nkind (A) /= N_Aggregate then
- if Is_Overloaded (A) then
- A_Type := Any_Type;
- Get_First_Interp (A, I, It);
-
- while Present (It.Typ) loop
-
- if Is_Tagged_Type (It.Typ)
- and then not Is_Limited_Type (It.Typ)
- then
- if A_Type /= Any_Type then
- Error_Msg_N ("cannot resolve expression", A);
- return;
- else
- A_Type := It.Typ;
- end if;
- end if;
-
- Get_Next_Interp (I, It);
- end loop;
-
- if A_Type = Any_Type then
- Error_Msg_N
- ("ancestor part must be non-limited tagged type", A);
- return;
- end if;
-
- else
- A_Type := Etype (A);
- end if;
-
- if Valid_Ancestor_Type then
- Resolve (A, A_Type);
- Check_Non_Static_Context (A);
- Resolve_Record_Aggregate (N, Typ);
- end if;
-
- else
- Error_Msg_N (" No unique type for this aggregate", A);
- end if;
-
- end Resolve_Extension_Aggregate;
-
- ------------------------------
- -- Resolve_Record_Aggregate --
- ------------------------------
-
- procedure Resolve_Record_Aggregate (N : Node_Id; Typ : Entity_Id) is
- Regular_Aggr : constant Boolean := Nkind (N) /= N_Extension_Aggregate;
-
- New_Assoc_List : List_Id := New_List;
- New_Assoc : Node_Id;
- -- New_Assoc_List is the newly built list of N_Component_Association
- -- nodes. New_Assoc is one such N_Component_Association node in it.
- -- Please note that while Assoc and New_Assoc contain the same
- -- kind of nodes, they are used to iterate over two different
- -- N_Component_Association lists.
-
- Others_Etype : Entity_Id := Empty;
- -- This variable is used to save the Etype of the last record component
- -- that takes its value from the others choice. Its purpose is:
- --
- -- (a) make sure the others choice is useful
- --
- -- (b) make sure the type of all the components whose value is
- -- subsumed by the others choice are the same.
- --
- -- This variable is updated as a side effect of function Get_Value
-
- procedure Add_Association (Component : Entity_Id; Expr : Node_Id);
- -- Builds a new N_Component_Association node which associates
- -- Component to expression Expr and adds it to the new association
- -- list New_Assoc_List being built.
-
- function Discr_Present (Discr : Entity_Id) return Boolean;
- -- If aggregate N is a regular aggregate this routine will return True.
- -- Otherwise, if N is an extension aggreagte, Discr is a discriminant
- -- whose value may already have been specified by N's ancestor part,
- -- this routine checks whether this is indeed the case and if so
- -- returns False, signaling that no value for Discr should appear in the
- -- N's aggregate part. Also, in this case, the routine appends to
- -- New_Assoc_List Discr the discriminant value specified in the ancestor
- -- part.
-
- function Get_Value
- (Compon : Node_Id;
- From : List_Id;
- Consider_Others_Choice : Boolean := False)
- return Node_Id;
- -- Given a record component stored in parameter Compon, the
- -- following function returns its value as it appears in the list
- -- From, which is a list of N_Component_Association nodes. If no
- -- component association has a choice for the searched component,
- -- the value provided by the others choice is returned, if there
- -- is one and Consider_Others_Choice is set to true. Otherwise
- -- Empty is returned. If there is more than one component association
- -- giving a value for the searched record component, an error message
- -- is emitted and the first found value is returned.
- --
- -- If Consider_Others_Choice is set and the returned expression comes
- -- from the others choice, then Others_Etype is set as a side effect.
- -- An error message is emitted if the components taking their value
- -- from the others choice do not have same type.
-
- procedure Resolve_Aggr_Expr (Expr : Node_Id; Component : Node_Id);
- -- Analyzes and resolves expression Expr against the Etype of the
- -- Component. This routine also applies all appropriate checks to Expr.
- -- It finally saves a Expr in the newly created association list that
- -- will be attached to the final record aggregate. Note that if the
- -- Parent pointer of Expr is not set then Expr was produced with a
- -- New_copy_Tree or some such.
-
- ---------------------
- -- Add_Association --
- ---------------------
-
- procedure Add_Association (Component : Entity_Id; Expr : Node_Id) is
- New_Assoc : Node_Id;
- Choice_List : List_Id := New_List;
-
- begin
- Append (New_Occurrence_Of (Component, Sloc (Expr)), Choice_List);
- New_Assoc :=
- Make_Component_Association (Sloc (Expr),
- Choices => Choice_List,
- Expression => Expr);
- Append (New_Assoc, New_Assoc_List);
- end Add_Association;
-
- -------------------
- -- Discr_Present --
- -------------------
-
- function Discr_Present (Discr : Entity_Id) return Boolean is
- Loc : Source_Ptr;
-
- Ancestor : Node_Id;
- Discr_Expr : Node_Id;
-
- Ancestor_Typ : Entity_Id;
- Orig_Discr : Entity_Id;
- D : Entity_Id;
- D_Val : Elmt_Id := No_Elmt; -- stop junk warning
-
- Ancestor_Is_Subtyp : Boolean;
-
- begin
- if Regular_Aggr then
- return True;
- end if;
-
- Ancestor := Ancestor_Part (N);
- Ancestor_Typ := Etype (Ancestor);
- Loc := Sloc (Ancestor);
-
- Ancestor_Is_Subtyp :=
- Is_Entity_Name (Ancestor) and then Is_Type (Entity (Ancestor));
-
- -- If the ancestor part has no discriminants clearly N's aggregate
- -- part must provide a value for Discr.
-
- if not Has_Discriminants (Ancestor_Typ) then
- return True;
-
- -- If the ancestor part is an unconstrained subtype mark then the
- -- Discr must be present in N's aggregate part.
-
- elsif Ancestor_Is_Subtyp
- and then not Is_Constrained (Entity (Ancestor))
- then
- return True;
- end if;
-
- -- Now look to see if Discr was specified in the ancestor part.
-
- Orig_Discr := Original_Record_Component (Discr);
- D := First_Discriminant (Ancestor_Typ);
-
- if Ancestor_Is_Subtyp then
- D_Val := First_Elmt (Discriminant_Constraint (Entity (Ancestor)));
- end if;
-
- while Present (D) loop
- -- If Ancestor has already specified Disc value than
- -- insert its value in the final aggregate.
-
- if Original_Record_Component (D) = Orig_Discr then
- if Ancestor_Is_Subtyp then
- Discr_Expr := New_Copy_Tree (Node (D_Val));
- else
- Discr_Expr :=
- Make_Selected_Component (Loc,
- Prefix => Duplicate_Subexpr (Ancestor),
- Selector_Name => New_Occurrence_Of (Discr, Loc));
- end if;
-
- Resolve_Aggr_Expr (Discr_Expr, Discr);
- return False;
- end if;
-
- Next_Discriminant (D);
-
- if Ancestor_Is_Subtyp then
- Next_Elmt (D_Val);
- end if;
- end loop;
-
- return True;
- end Discr_Present;
-
- ---------------
- -- Get_Value --
- ---------------
-
- function Get_Value
- (Compon : Node_Id;
- From : List_Id;
- Consider_Others_Choice : Boolean := False)
- return Node_Id
- is
- Assoc : Node_Id;
- Expr : Node_Id := Empty;
- Selector_Name : Node_Id;
-
- begin
- if Present (From) then
- Assoc := First (From);
- else
- return Empty;
- end if;
-
- while Present (Assoc) loop
- Selector_Name := First (Choices (Assoc));
- while Present (Selector_Name) loop
- if Nkind (Selector_Name) = N_Others_Choice then
- if Consider_Others_Choice and then No (Expr) then
- if Present (Others_Etype) and then
- Base_Type (Others_Etype) /= Base_Type (Etype (Compon))
- then
- Error_Msg_N ("components in OTHERS choice must " &
- "have same type", Selector_Name);
- end if;
-
- Others_Etype := Etype (Compon);
-
- -- We need to duplicate the expression for each
- -- successive component covered by the others choice.
- -- If the expression is itself an array aggregate with
- -- "others", its subtype must be obtained from the
- -- current component, and therefore it must be (at least
- -- partly) reanalyzed.
-
- if Analyzed (Expression (Assoc)) then
- Expr := New_Copy_Tree (Expression (Assoc));
-
- if Nkind (Expr) = N_Aggregate
- and then Is_Array_Type (Etype (Expr))
- and then No (Expressions (Expr))
- and then
- Nkind (First (Choices
- (First (Component_Associations (Expr)))))
- = N_Others_Choice
- then
- Set_Analyzed (Expr, False);
- end if;
-
- return Expr;
-
- else
- return Expression (Assoc);
- end if;
- end if;
-
- elsif Chars (Compon) = Chars (Selector_Name) then
- if No (Expr) then
- -- We need to duplicate the expression when several
- -- components are grouped together with a "|" choice.
- -- For instance "filed1 | filed2 => Expr"
-
- if Present (Next (Selector_Name)) then
- Expr := New_Copy_Tree (Expression (Assoc));
- else
- Expr := Expression (Assoc);
- end if;
-
- else
- Error_Msg_NE
- ("more than one value supplied for &",
- Selector_Name, Compon);
-
- end if;
- end if;
-
- Next (Selector_Name);
- end loop;
-
- Next (Assoc);
- end loop;
-
- return Expr;
- end Get_Value;
-
- -----------------------
- -- Resolve_Aggr_Expr --
- -----------------------
-
- procedure Resolve_Aggr_Expr (Expr : Node_Id; Component : Node_Id) is
- New_C : Entity_Id := Component;
- Expr_Type : Entity_Id := Empty;
-
- function Has_Expansion_Delayed (Expr : Node_Id) return Boolean;
- -- If the expression is an aggregate (possibly qualified) then its
- -- expansion is delayed until the enclosing aggregate is expanded
- -- into assignments. In that case, do not generate checks on the
- -- expression, because they will be generated later, and will other-
- -- wise force a copy (to remove side-effects) that would leave a
- -- dynamic-sized aggregate in the code, something that gigi cannot
- -- handle.
-
- Relocate : Boolean;
- -- Set to True if the resolved Expr node needs to be relocated
- -- when attached to the newly created association list. This node
- -- need not be relocated if its parent pointer is not set.
- -- In fact in this case Expr is the output of a New_Copy_Tree call.
- -- if Relocate is True then we have analyzed the expression node
- -- in the original aggregate and hence it needs to be relocated
- -- when moved over the new association list.
-
- function Has_Expansion_Delayed (Expr : Node_Id) return Boolean is
- Kind : constant Node_Kind := Nkind (Expr);
-
- begin
- return ((Kind = N_Aggregate
- or else Kind = N_Extension_Aggregate)
- and then Present (Etype (Expr))
- and then Is_Record_Type (Etype (Expr))
- and then Expansion_Delayed (Expr))
-
- or else (Kind = N_Qualified_Expression
- and then Has_Expansion_Delayed (Expression (Expr)));
- end Has_Expansion_Delayed;
-
- -- Start of processing for Resolve_Aggr_Expr
-
- begin
- -- If the type of the component is elementary or the type of the
- -- aggregate does not contain discriminants, use the type of the
- -- component to resolve Expr.
-
- if Is_Elementary_Type (Etype (Component))
- or else not Has_Discriminants (Etype (N))
- then
- Expr_Type := Etype (Component);
-
- -- Otherwise we have to pick up the new type of the component from
- -- the new costrained subtype of the aggregate. In fact components
- -- which are of a composite type might be constrained by a
- -- discriminant, and we want to resolve Expr against the subtype were
- -- all discriminant occurrences are replaced with their actual value.
-
- else
- New_C := First_Component (Etype (N));
- while Present (New_C) loop
- if Chars (New_C) = Chars (Component) then
- Expr_Type := Etype (New_C);
- exit;
- end if;
-
- Next_Component (New_C);
- end loop;
-
- pragma Assert (Present (Expr_Type));
-
- -- For each range in an array type where a discriminant has been
- -- replaced with the constraint, check that this range is within
- -- the range of the base type. This checks is done in the
- -- _init_proc for regular objects, but has to be done here for
- -- aggregates since no _init_proc is called for them.
-
- if Is_Array_Type (Expr_Type) then
- declare
- Index : Node_Id := First_Index (Expr_Type);
- -- Range of the current constrained index in the array.
-
- Orig_Index : Node_Id := First_Index (Etype (Component));
- -- Range corresponding to the range Index above in the
- -- original unconstrained record type. The bounds of this
- -- range may be governed by discriminants.
-
- Unconstr_Index : Node_Id := First_Index (Etype (Expr_Type));
- -- Range corresponding to the range Index above for the
- -- unconstrained array type. This range is needed to apply
- -- range checks.
-
- begin
- while Present (Index) loop
- if Depends_On_Discriminant (Orig_Index) then
- Apply_Range_Check (Index, Etype (Unconstr_Index));
- end if;
-
- Next_Index (Index);
- Next_Index (Orig_Index);
- Next_Index (Unconstr_Index);
- end loop;
- end;
- end if;
- end if;
-
- -- If the Parent pointer of Expr is not set, Expr is an expression
- -- duplicated by New_Tree_Copy (this happens for record aggregates
- -- that look like (Field1 | Filed2 => Expr) or (others => Expr)).
- -- Such a duplicated expression must be attached to the tree
- -- before analysis and resolution to enforce the rule that a tree
- -- fragment should never be analyzed or resolved unless it is
- -- attached to the current compilation unit.
-
- if No (Parent (Expr)) then
- Set_Parent (Expr, N);
- Relocate := False;
- else
- Relocate := True;
- end if;
-
- Analyze_And_Resolve (Expr, Expr_Type);
- Check_Non_Static_Context (Expr);
-
- if not Has_Expansion_Delayed (Expr) then
- Aggregate_Constraint_Checks (Expr, Expr_Type);
- end if;
-
- if Raises_Constraint_Error (Expr) then
- Set_Raises_Constraint_Error (N);
- end if;
-
- if Relocate then
- Add_Association (New_C, Relocate_Node (Expr));
- else
- Add_Association (New_C, Expr);
- end if;
-
- end Resolve_Aggr_Expr;
-
- -- Resolve_Record_Aggregate local variables
-
- Assoc : Node_Id;
- -- N_Component_Association node belonging to the input aggregate N
-
- Expr : Node_Id;
- Positional_Expr : Node_Id;
-
- Component : Entity_Id;
- Component_Elmt : Elmt_Id;
- Components : Elist_Id := New_Elmt_List;
- -- Components is the list of the record components whose value must
- -- be provided in the aggregate. This list does include discriminants.
-
- -- Start of processing for Resolve_Record_Aggregate
-
- begin
- -- We may end up calling Duplicate_Subexpr on expressions that are
- -- attached to New_Assoc_List. For this reason we need to attach it
- -- to the tree by setting its parent pointer to N. This parent point
- -- will change in STEP 8 below.
-
- Set_Parent (New_Assoc_List, N);
-
- -- STEP 1: abstract type and null record verification
-
- if Is_Abstract (Typ) then
- Error_Msg_N ("type of aggregate cannot be abstract", N);
- end if;
-
- if No (First_Entity (Typ)) and then Null_Record_Present (N) then
- Set_Etype (N, Typ);
- return;
-
- elsif Present (First_Entity (Typ))
- and then Null_Record_Present (N)
- and then not Is_Tagged_Type (Typ)
- then
- Error_Msg_N ("record aggregate cannot be null", N);
- return;
-
- elsif No (First_Entity (Typ)) then
- Error_Msg_N ("record aggregate must be null", N);
- return;
- end if;
-
- -- STEP 2: Verify aggregate structure
-
- Step_2 : declare
- Selector_Name : Node_Id;
- Bad_Aggregate : Boolean := False;
-
- begin
- if Present (Component_Associations (N)) then
- Assoc := First (Component_Associations (N));
- else
- Assoc := Empty;
- end if;
-
- while Present (Assoc) loop
- Selector_Name := First (Choices (Assoc));
- while Present (Selector_Name) loop
- if Nkind (Selector_Name) = N_Identifier then
- null;
-
- elsif Nkind (Selector_Name) = N_Others_Choice then
- if Selector_Name /= First (Choices (Assoc))
- or else Present (Next (Selector_Name))
- then
- Error_Msg_N ("OTHERS must appear alone in a choice list",
- Selector_Name);
- return;
-
- elsif Present (Next (Assoc)) then
- Error_Msg_N ("OTHERS must appear last in an aggregate",
- Selector_Name);
- return;
- end if;
-
- else
- Error_Msg_N
- ("selector name should be identifier or OTHERS",
- Selector_Name);
- Bad_Aggregate := True;
- end if;
-
- Next (Selector_Name);
- end loop;
-
- Next (Assoc);
- end loop;
-
- if Bad_Aggregate then
- return;
- end if;
- end Step_2;
-
- -- STEP 3: Find discriminant Values
-
- Step_3 : declare
- Discrim : Entity_Id;
- Missing_Discriminants : Boolean := False;
-
- begin
- if Present (Expressions (N)) then
- Positional_Expr := First (Expressions (N));
- else
- Positional_Expr := Empty;
- end if;
-
- if Has_Discriminants (Typ) then
- Discrim := First_Discriminant (Typ);
- else
- Discrim := Empty;
- end if;
-
- -- First find the discriminant values in the positional components
-
- while Present (Discrim) and then Present (Positional_Expr) loop
- if Discr_Present (Discrim) then
- Resolve_Aggr_Expr (Positional_Expr, Discrim);
- Next (Positional_Expr);
- end if;
-
- if Present (Get_Value (Discrim, Component_Associations (N))) then
- Error_Msg_NE
- ("more than one value supplied for discriminant&",
- N, Discrim);
- end if;
-
- Next_Discriminant (Discrim);
- end loop;
-
- -- Find remaining discriminant values, if any, among named components
-
- while Present (Discrim) loop
- Expr := Get_Value (Discrim, Component_Associations (N), True);
-
- if not Discr_Present (Discrim) then
- if Present (Expr) then
- Error_Msg_NE
- ("more than one value supplied for discriminant&",
- N, Discrim);
- end if;
-
- elsif No (Expr) then
- Error_Msg_NE
- ("no value supplied for discriminant &", N, Discrim);
- Missing_Discriminants := True;
-
- else
- Resolve_Aggr_Expr (Expr, Discrim);
- end if;
-
- Next_Discriminant (Discrim);
- end loop;
-
- if Missing_Discriminants then
- return;
- end if;
-
- -- At this point and until the beginning of STEP 6, New_Assoc_List
- -- contains only the discriminants and their values.
-
- end Step_3;
-
- -- STEP 4: Set the Etype of the record aggregate
-
- -- ??? This code is pretty much a copy of Sem_Ch3.Build_Subtype. That
- -- routine should really be exported in sem_util or some such and used
- -- in sem_ch3 and here rather than have a copy of the code which is a
- -- maintenance nightmare.
-
- -- ??? Performace WARNING. The current implementation creates a new
- -- itype for all aggregates whose base type is discriminated.
- -- This means that for record aggregates nested inside an array
- -- aggregate we will create a new itype for each record aggregate
- -- if the array cmponent type has discriminants. For large aggregates
- -- this may be a problem. What should be done in this case is
- -- to reuse itypes as much as possible.
-
- if Has_Discriminants (Typ) then
- Build_Constrained_Itype : declare
- Loc : constant Source_Ptr := Sloc (N);
- Indic : Node_Id;
- Subtyp_Decl : Node_Id;
- Def_Id : Entity_Id;
-
- C : List_Id := New_List;
-
- begin
- New_Assoc := First (New_Assoc_List);
- while Present (New_Assoc) loop
- Append (Duplicate_Subexpr (Expression (New_Assoc)), To => C);
- Next (New_Assoc);
- end loop;
-
- Indic :=
- Make_Subtype_Indication (Loc,
- Subtype_Mark => New_Occurrence_Of (Base_Type (Typ), Loc),
- Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
-
- Def_Id := Create_Itype (Ekind (Typ), N);
-
- Subtyp_Decl :=
- Make_Subtype_Declaration (Loc,
- Defining_Identifier => Def_Id,
- Subtype_Indication => Indic);
- Set_Parent (Subtyp_Decl, Parent (N));
-
- -- Itypes must be analyzed with checks off (see itypes.ads).
-
- Analyze (Subtyp_Decl, Suppress => All_Checks);
-
- Set_Etype (N, Def_Id);
- Check_Static_Discriminated_Subtype
- (Def_Id, Expression (First (New_Assoc_List)));
- end Build_Constrained_Itype;
-
- else
- Set_Etype (N, Typ);
- end if;
-
- -- STEP 5: Get remaining components according to discriminant values
-
- Step_5 : declare
- Record_Def : Node_Id;
- Parent_Typ : Entity_Id;
- Root_Typ : Entity_Id;
- Parent_Typ_List : Elist_Id;
- Parent_Elmt : Elmt_Id;
- Errors_Found : Boolean := False;
- Dnode : Node_Id;
-
- begin
- if Is_Derived_Type (Typ) and then Is_Tagged_Type (Typ) then
- Parent_Typ_List := New_Elmt_List;
-
- -- If this is an extension aggregate, the component list must
- -- include all components that are not in the given ancestor
- -- type. Otherwise, the component list must include components
- -- of all ancestors.
-
- if Nkind (N) = N_Extension_Aggregate then
- Root_Typ := Base_Type (Etype (Ancestor_Part (N)));
- else
- Root_Typ := Root_Type (Typ);
-
- if Nkind (Parent (Base_Type (Root_Typ)))
- = N_Private_Type_Declaration
- then
- Error_Msg_NE
- ("type of aggregate has private ancestor&!",
- N, Root_Typ);
- Error_Msg_N ("must use extension aggregate!", N);
- return;
- end if;
-
- Dnode := Declaration_Node (Base_Type (Root_Typ));
-
- -- If we don't get a full declaration, then we have some
- -- error which will get signalled later so skip this part.
-
- if Nkind (Dnode) = N_Full_Type_Declaration then
- Record_Def := Type_Definition (Dnode);
- Gather_Components (Typ,
- Component_List (Record_Def),
- Governed_By => New_Assoc_List,
- Into => Components,
- Report_Errors => Errors_Found);
- end if;
- end if;
-
- Parent_Typ := Base_Type (Typ);
- while Parent_Typ /= Root_Typ loop
-
- Prepend_Elmt (Parent_Typ, To => Parent_Typ_List);
- Parent_Typ := Etype (Parent_Typ);
-
- if (Nkind (Parent (Base_Type (Parent_Typ))) =
- N_Private_Type_Declaration
- or else Nkind (Parent (Base_Type (Parent_Typ))) =
- N_Private_Extension_Declaration)
- then
- if Nkind (N) /= N_Extension_Aggregate then
- Error_Msg_NE
- ("type of aggregate has private ancestor&!",
- N, Parent_Typ);
- Error_Msg_N ("must use extension aggregate!", N);
- return;
-
- elsif Parent_Typ /= Root_Typ then
- Error_Msg_NE
- ("ancestor part of aggregate must be private type&",
- Ancestor_Part (N), Parent_Typ);
- return;
- end if;
- end if;
- end loop;
-
- -- Now collect components from all other ancestors.
-
- Parent_Elmt := First_Elmt (Parent_Typ_List);
- while Present (Parent_Elmt) loop
- Parent_Typ := Node (Parent_Elmt);
- Record_Def := Type_Definition (Parent (Base_Type (Parent_Typ)));
- Gather_Components (Empty,
- Component_List (Record_Extension_Part (Record_Def)),
- Governed_By => New_Assoc_List,
- Into => Components,
- Report_Errors => Errors_Found);
-
- Next_Elmt (Parent_Elmt);
- end loop;
-
- else
- Record_Def := Type_Definition (Parent (Base_Type (Typ)));
-
- if Null_Present (Record_Def) then
- null;
- else
- Gather_Components (Typ,
- Component_List (Record_Def),
- Governed_By => New_Assoc_List,
- Into => Components,
- Report_Errors => Errors_Found);
- end if;
- end if;
-
- if Errors_Found then
- return;
- end if;
- end Step_5;
-
- -- STEP 6: Find component Values
-
- Component := Empty;
- Component_Elmt := First_Elmt (Components);
-
- -- First scan the remaining positional associations in the aggregate.
- -- Remember that at this point Positional_Expr contains the current
- -- positional association if any is left after looking for discriminant
- -- values in step 3.
-
- while Present (Positional_Expr) and then Present (Component_Elmt) loop
- Component := Node (Component_Elmt);
- Resolve_Aggr_Expr (Positional_Expr, Component);
-
- if Present (Get_Value (Component, Component_Associations (N))) then
- Error_Msg_NE
- ("more than one value supplied for Component &", N, Component);
- end if;
-
- Next (Positional_Expr);
- Next_Elmt (Component_Elmt);
- end loop;
-
- if Present (Positional_Expr) then
- Error_Msg_N
- ("too many components for record aggregate", Positional_Expr);
- end if;
-
- -- Now scan for the named arguments of the aggregate
-
- while Present (Component_Elmt) loop
- Component := Node (Component_Elmt);
- Expr := Get_Value (Component, Component_Associations (N), True);
-
- if No (Expr) then
- Error_Msg_NE ("no value supplied for component &!", N, Component);
- else
- Resolve_Aggr_Expr (Expr, Component);
- end if;
-
- Next_Elmt (Component_Elmt);
- end loop;
-
- -- STEP 7: check for invalid components + check type in choice list
-
- Step_7 : declare
- Selectr : Node_Id;
- -- Selector name
-
- Typech : Entity_Id;
- -- Type of first component in choice list
-
- begin
- if Present (Component_Associations (N)) then
- Assoc := First (Component_Associations (N));
- else
- Assoc := Empty;
- end if;
-
- Verification : while Present (Assoc) loop
- Selectr := First (Choices (Assoc));
- Typech := Empty;
-
- if Nkind (Selectr) = N_Others_Choice then
- if No (Others_Etype) then
- Error_Msg_N
- ("OTHERS must represent at least one component", Selectr);
- end if;
-
- exit Verification;
- end if;
-
- while Present (Selectr) loop
- New_Assoc := First (New_Assoc_List);
- while Present (New_Assoc) loop
- Component := First (Choices (New_Assoc));
- exit when Chars (Selectr) = Chars (Component);
- Next (New_Assoc);
- end loop;
-
- -- If no association, this is not a legal component of
- -- of the type in question, except if this is an internal
- -- component supplied by a previous expansion.
-
- if No (New_Assoc) then
-
- if Chars (Selectr) /= Name_uTag
- and then Chars (Selectr) /= Name_uParent
- and then Chars (Selectr) /= Name_uController
- then
- if not Has_Discriminants (Typ) then
- Error_Msg_Node_2 := Typ;
- Error_Msg_N
- ("& is not a component of}",
- Selectr);
- else
- Error_Msg_N
- ("& is not a component of the aggregate subtype",
- Selectr);
- end if;
-
- Check_Misspelled_Component (Components, Selectr);
- end if;
-
- elsif No (Typech) then
- Typech := Base_Type (Etype (Component));
-
- elsif Typech /= Base_Type (Etype (Component)) then
- Error_Msg_N
- ("components in choice list must have same type", Selectr);
- end if;
-
- Next (Selectr);
- end loop;
-
- Next (Assoc);
- end loop Verification;
- end Step_7;
-
- -- STEP 8: replace the original aggregate
-
- Step_8 : declare
- New_Aggregate : Node_Id := New_Copy (N);
-
- begin
- Set_Expressions (New_Aggregate, No_List);
- Set_Etype (New_Aggregate, Etype (N));
- Set_Component_Associations (New_Aggregate, New_Assoc_List);
-
- Rewrite (N, New_Aggregate);
- end Step_8;
- end Resolve_Record_Aggregate;
-
- ---------------------
- -- Sort_Case_Table --
- ---------------------
-
- procedure Sort_Case_Table (Case_Table : in out Case_Table_Type) is
- L : Int := Case_Table'First;
- U : Int := Case_Table'Last;
- K : Int;
- J : Int;
- T : Case_Bounds;
-
- begin
- K := L;
-
- while K /= U loop
- T := Case_Table (K + 1);
- J := K + 1;
-
- while J /= L
- and then Expr_Value (Case_Table (J - 1).Choice_Lo) >
- Expr_Value (T.Choice_Lo)
- loop
- Case_Table (J) := Case_Table (J - 1);
- J := J - 1;
- end loop;
-
- Case_Table (J) := T;
- K := K + 1;
- end loop;
- end Sort_Case_Table;
-
-end Sem_Aggr;
projects / msp430-gcc.git / blobdiff