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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- F R E E Z E --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2015, Free Software Foundation, Inc. --
10 -- --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
20 -- --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
23 -- --
24 ------------------------------------------------------------------------------
73 -----------------------
74 -- Local Subprograms --
75 -----------------------
78 -- Typ is a type that is being frozen. If no size clause is given,
79 -- but a default Esize has been computed, then this default Esize is
80 -- adjusted up if necessary to be consistent with a given alignment,
81 -- but never to a value greater than Long_Long_Integer'Size. This
82 -- is used for all discrete types and for fixed-point types.
84 procedure Build_And_Analyze_Renamed_Body
88 -- Build body for a renaming declaration, insert in tree and analyze
91 -- Apply legality checks to address clauses for object declarations,
92 -- at the point the object is frozen. Also ensure any initialization is
93 -- performed only after the object has been frozen.
95 procedure Check_Component_Storage_Order
100 -- For an Encl_Type that has a Scalar_Storage_Order attribute definition
101 -- clause, verify that the component type has an explicit and compatible
102 -- attribute/aspect. For arrays, Comp is Empty; for records, it is the
103 -- entity of the component under consideration. For an Encl_Type that
104 -- does not have a Scalar_Storage_Order attribute definition clause,
105 -- verify that the component also does not have such a clause.
106 -- ADC is the attribute definition clause if present (or Empty). On return,
107 -- Comp_ADC_Present is set True if the component has a Scalar_Storage_Order
108 -- attribute definition clause.
111 -- When an expression function is frozen by a use of it, the expression
112 -- itself is frozen. Check that the expression does not include references
113 -- to deferred constants without completion. We report this at the freeze
114 -- point of the function, to provide a better error message.
115 --
116 -- In most cases the expression itself is frozen by the time the function
117 -- itself is frozen, because the formals will be frozen by then. However,
118 -- Attribute references to outer types are freeze points for those types;
119 -- this routine generates the required freeze nodes for them.
122 -- E is a base type. If E is tagged or has a component that is aliased
123 -- or tagged or contains something this is aliased or tagged, set
124 -- Strict_Alignment.
128 -- If E is a fixed-point or discrete type, then all the necessary work
129 -- to freeze it is completed except for possible setting of the flag
130 -- Is_Unsigned_Type, which is done by this procedure. The call has no
131 -- effect if the entity E is not a discrete or fixed-point type.
133 procedure Freeze_And_Append
137 -- Freezes Ent using Freeze_Entity, and appends the resulting list of
138 -- nodes to Result, modifying Result from No_List if necessary. N has
139 -- the same usage as in Freeze_Entity.
142 -- Freeze enumeration type. The Esize field is set as processing
143 -- proceeds (i.e. set by default when the type is declared and then
144 -- adjusted by rep clauses. What this procedure does is to make sure
145 -- that if a foreign convention is specified, and no specific size
146 -- is given, then the size must be at least Integer'Size.
149 -- If an object is frozen which has Is_Statically_Allocated set, then
150 -- all referenced types must also be marked with this flag. This routine
151 -- is in charge of meeting this requirement for the object entity E.
154 -- Perform freezing actions for a subprogram (create extra formals,
155 -- and set proper default mechanism values). Note that this routine
156 -- is not called for internal subprograms, for which neither of these
157 -- actions is needed (or desirable, we do not want for example to have
158 -- these extra formals present in initialization procedures, where they
159 -- would serve no purpose). In this call E is either a subprogram or
160 -- a subprogram type (i.e. an access to a subprogram).
163 -- True if T is not private and has no private components, or has a full
164 -- view. Used to determine whether the designated type of an access type
165 -- should be frozen when the access type is frozen. This is done when an
166 -- allocator is frozen, or an expression that may involve attributes of
167 -- the designated type. Otherwise freezing the access type does not freeze
168 -- the designated type.
170 procedure Process_Default_Expressions
173 -- This procedure is called for each subprogram to complete processing of
174 -- default expressions at the point where all types are known to be frozen.
175 -- The expressions must be analyzed in full, to make sure that all error
176 -- processing is done (they have only been pre-analyzed). If the expression
177 -- is not an entity or literal, its analysis may generate code which must
178 -- not be executed. In that case we build a function body to hold that
179 -- code. This wrapper function serves no other purpose (it used to be
180 -- called to evaluate the default, but now the default is inlined at each
181 -- point of call).
184 -- Typ is a record or array type that is being frozen. This routine sets
185 -- the default component alignment from the scope stack values if the
186 -- alignment is otherwise not specified.
189 -- As each entity is frozen, this routine is called to deal with the
190 -- setting of Debug_Info_Needed for the entity. This flag is set if
191 -- the entity comes from source, or if we are in Debug_Generated_Code
192 -- mode or if the -gnatdV debug flag is set. However, it never sets
193 -- the flag if Debug_Info_Off is set. This procedure also ensures that
194 -- subsidiary entities have the flag set as required.
197 -- T is a record or array type that is being frozen. If it is a base type,
198 -- and if SSO_Set_Low/High_By_Default is set, then Reverse_Storage order
199 -- will be set appropriately. Note that an explicit occurrence of aspect
200 -- Scalar_Storage_Order or an explicit setting of this aspect with an
201 -- attribute definition clause occurs, then these two flags are reset in
202 -- any case, so call will have no effect.
205 -- T is a type of a component that we know to be an Itype. We don't want
206 -- this to have a Freeze_Node, so ensure it doesn't. Do the same for any
207 -- Full_View or Corresponding_Record_Type.
209 procedure Warn_Overlay
213 -- Expr is the expression for an address clause for entity Nam whose type
214 -- is Typ. If Typ has a default initialization, and there is no explicit
215 -- initialization in the source declaration, check whether the address
216 -- clause might cause overlaying of an entity, and emit a warning on the
217 -- side effect that the initialization will cause.
219 -------------------------------
220 -- Adjust_Esize_For_Alignment --
221 -------------------------------
226 begin
232 then
238 ------------------------------------
239 -- Build_And_Analyze_Renamed_Body --
240 ------------------------------------
242 procedure Build_And_Analyze_Renamed_Body
246 is
252 begin
253 -- If the renamed subprogram is intrinsic, there is no need for a
254 -- wrapper body: we set the alias that will be called and expanded which
255 -- completes the declaration. This transformation is only legal if the
256 -- renamed entity has already been elaborated.
258 -- Note that it is legal for a renaming_as_body to rename an intrinsic
259 -- subprogram, as long as the renaming occurs before the new entity
260 -- is frozen (RM 8.5.4 (5)).
264 then
266 else
272 and then
276 -- We can make the renaming entity intrinsic if the renamed function
277 -- has an interface name, or if it is one of the shift/rotate
278 -- operations known to the compiler.
280 and then
283 Name_Rotate_Right,
284 Name_Shift_Left,
285 Name_Shift_Right,
286 Name_Shift_Right_Arithmetic))
287 then
292 else
299 else
308 ------------------------
309 -- Build_Renamed_Body --
310 ------------------------
312 function Build_Renamed_Body
315 is
317 -- We use for the source location of the renamed body, the location of
318 -- the spec entity. It might seem more natural to use the location of
319 -- the renaming declaration itself, but that would be wrong, since then
320 -- the body we create would look as though it was created far too late,
321 -- and this could cause problems with elaboration order analysis,
322 -- particularly in connection with instantiations.
337 -- If the renamed entity is a primitive operation given in prefix form,
338 -- the prefix is the target object and it has to be added as the first
339 -- actual in the generated call.
341 begin
342 -- Determine the entity being renamed, which is the target of the call
343 -- statement. If the name is an explicit dereference, this is a renaming
344 -- of a subprogram type rather than a subprogram. The name itself is
345 -- fully analyzed.
356 else
363 else
369 -- If the renamed entity is a predefined operator, retain full name
370 -- to ensure its visibility.
374 then
376 else
380 else
383 and then
386 then
388 -- Retrieve the target object, to be added as a first actual
389 -- in the call.
394 else
398 -- Original name may have been overloaded, but is fully resolved now
403 -- For simple renamings, subsequent calls can be expanded directly as
404 -- calls to the renamed entity. The body must be generated in any case
405 -- for calls that may appear elsewhere. This is not done in the case
406 -- where the subprogram is an instantiation because the actual proper
407 -- body has not been built yet.
412 then
416 -- Check whether the return type is a limited view. If the subprogram
417 -- is already frozen the generated body may have a non-limited view
418 -- of the type, that must be used, because it is the one in the spec
419 -- of the renaming declaration.
423 then
424 declare
426 begin
428 Set_Result_Definition
434 -- The body generated for this renaming is an internal artifact, and
435 -- does not constitute a freeze point for the called entity.
442 declare
446 begin
447 -- The controlling formal may be an access parameter, or the
448 -- actual may be an access value, so adjust accordingly.
452 then
453 Actuals := New_List
458 then
459 Actuals :=
460 New_List (
464 else
472 else
483 -- If the renamed entity is an entry, inherit its profile. For other
484 -- renamings as bodies, both profiles must be subtype conformant, so it
485 -- is not necessary to replace the profile given in the declaration.
486 -- However, default values that are aggregates are rewritten when
487 -- partially analyzed, so we recover the original aggregate to insure
488 -- that subsequent conformity checking works. Similarly, if the default
489 -- expression was constant-folded, recover the original expression.
499 N_Access_Definition
500 then
508 then
519 -- If the renamed entity is a function, the generated body contains a
520 -- return statement. Otherwise, build a procedure call. If the entity is
521 -- an entry, subsequent analysis of the call will transform it into the
522 -- proper entry or protected operation call. If the renamed entity is
523 -- a character literal, return it directly.
529 then
530 Call_Node :=
532 Expression =>
538 Call_Node :=
543 Call_Node :=
546 else
547 Call_Node :=
553 -- Create entities for subprogram body and formals
566 Body_Node :=
570 Handled_Statement_Sequence =>
580 -- Link the body to the entity whose declaration it completes. If
581 -- the body is analyzed when the renamed entity is frozen, it may
582 -- be necessary to restore the proper scope (see package Exp_Ch13).
586 then
588 else
595 --------------------------
596 -- Check_Address_Clause --
597 --------------------------
608 begin
615 -- Has_Delayed_Freeze was set on E when the address clause was
616 -- analyzed, and must remain set because we want the address
617 -- clause to be elaborated only after any entity it references
618 -- has been elaborated.
621 -- If Rep_Clauses are to be ignored, remove address clause from
622 -- list attached to entity, because it may be illegal for gigi,
623 -- for example by breaking order of elaboration..
626 declare
629 begin
635 else
638 loop
648 -- And now remove the address clause
654 then
660 -- Capture initialization value at point of declaration,
661 -- and make explicit assignment legal, because object may
662 -- be a constant.
668 -- Move initialization to freeze actions (once the object has
669 -- been frozen, and the address clause alignment check has been
670 -- performed.
679 -- If the objet is tagged, check whether the tag must be
680 -- reassigned expliitly.
690 -----------------------------
691 -- Check_Compile_Time_Size --
692 -----------------------------
697 -- Sets the compile time known size (32 bits or less) in the Esize
698 -- field, of T checking for a size clause that was given which attempts
699 -- to give a smaller size, and also checking for an alignment clause.
702 -- Recursive function that does all the work
705 -- If T is a constrained subtype, its size is not known if any of its
706 -- discriminant constraints is not static and it is not a null record.
707 -- The test is conservative and doesn't check that the components are
708 -- in fact constrained by non-static discriminant values. Could be made
709 -- more precise ???
711 --------------------
712 -- Set_Small_Size --
713 --------------------
716 begin
720 -- Check for bad size clause given
725 Error_Msg_NE
730 -- Set size if not set already
737 ----------------
738 -- Size_Known --
739 ----------------
748 begin
752 -- Always True for scalar types. This is true even for generic formal
753 -- scalar types. We used to return False in the latter case, but the
754 -- size is known at compile time, even in the template, we just do
755 -- not know the exact size but that's not the point of this routine.
759 then
762 -- Array types
766 -- String literals always have known size, and we can set it
773 -- Unconstrained types never have known at compile time size
778 -- Don't do any recursion on type with error posted, since we may
779 -- have a malformed type that leads us into a loop.
784 -- Otherwise if component size unknown, then array size unknown
790 -- Check for all indexes static, and also compute possible size
791 -- (in case it is less than 32 and may be packable).
793 declare
797 begin
806 else
814 then
817 else
822 else
834 -- Access types always have known at compile time sizes
839 -- For non-generic private types, go to underlying type if present
844 then
845 -- Don't do any recursion on type with error posted, since we may
846 -- have a malformed type that leads us into a loop.
850 else
854 -- Record types
858 -- A class-wide type is never considered to have a known size
863 -- A subtype of a variant record must not have non-static
864 -- discriminated components.
868 then
871 -- Don't do any recursion on type with error posted, since we may
872 -- have a malformed type that leads us into a loop.
878 -- Now look at the components of the record
880 declare
881 -- The following two variables are used to keep track of the
882 -- size of packed records if we can tell the size of the packed
883 -- record in the front end. Packed_Size_Known is True if so far
884 -- we can figure out the size. It is initialized to True for a
885 -- packed record, unless the record has discriminants or atomic
886 -- components or independent components.
888 -- The reason we eliminate the discriminated case is that
889 -- we don't know the way the back end lays out discriminated
890 -- packed records. If Packed_Size_Known is True, then
891 -- Packed_Size is the size in bits so far.
900 -- Size in bits so far
902 begin
903 -- Test for variant part present
909 N_Record_Definition
911 and then
912 Present (Variant_Part
914 then
915 -- If variant part is present, and type is unconstrained,
916 -- then we must have defaulted discriminants, or a size
917 -- clause must be present for the type, or else the size
918 -- is definitely not known at compile time.
921 and then
924 then
929 -- Loop through components
935 -- We do not know the packed size if there is a component
936 -- clause present (we possibly could, but this would only
937 -- help in the case of a record with partial rep clauses.
938 -- That's because in the case of full rep clauses, the
939 -- size gets figured out anyway by a different circuit).
945 -- We do not know the packed size for an atomic/VFA type
946 -- or component, or an independent type or component, or a
947 -- by-reference type or aliased component (because packing
948 -- does not touch these).
956 then
960 -- We need to identify a component that is an array where
961 -- the index type is an enumeration type with non-standard
962 -- representation, and some bound of the type depends on a
963 -- discriminant.
965 -- This is because gigi computes the size by doing a
966 -- substitution of the appropriate discriminant value in
967 -- the size expression for the base type, and gigi is not
968 -- clever enough to evaluate the resulting expression (which
969 -- involves a call to rep_to_pos) at compile time.
971 -- It would be nice if gigi would either recognize that
972 -- this expression can be computed at compile time, or
973 -- alternatively figured out the size from the subtype
974 -- directly, where all the information is at hand ???
978 then
979 declare
987 begin
994 then
1000 then
1005 then
1015 -- Clearly size of record is not known if the size of one of
1016 -- the components is not known.
1022 -- Accumulate packed size if possible
1026 -- We can only deal with elementary types, since for
1027 -- non-elementary components, alignment enters into the
1028 -- picture, and we don't know enough to handle proper
1029 -- alignment in this context. Packed arrays count as
1030 -- elementary if the representation is a modular type.
1034 and then Present
1036 and then Is_Modular_Integer_Type
1038 then
1039 -- Packed size unknown if we have an atomic/VFA type
1040 -- or a by-reference type, since the back end knows
1041 -- how these are layed out.
1045 then
1048 -- If RM_Size is known and static, then we can keep
1049 -- accumulating the packed size
1053 -- A little glitch, to be removed sometime ???
1054 -- gigi does not understand zero sizes yet.
1059 -- Normal case where we can keep accumulating the
1060 -- packed array size.
1062 else
1066 -- If we have a field whose RM_Size is not known then
1067 -- we can't figure out the packed size here.
1069 else
1073 -- If we have a non-elementary type we can't figure out
1074 -- the packed array size (alignment issues).
1076 else
1091 -- All other cases, size not known at compile time
1093 else
1098 -------------------------------------
1099 -- Static_Discriminated_Components --
1100 -------------------------------------
1102 function Static_Discriminated_Components
1104 is
1107 begin
1111 then
1125 -- Start of processing for Check_Compile_Time_Size
1127 begin
1131 -----------------------------------
1132 -- Check_Component_Storage_Order --
1133 -----------------------------------
1135 procedure Check_Component_Storage_Order
1140 is
1146 -- Set for the record case, True if Comp starts on a byte boundary
1147 -- (in which case it is allowed to have different storage order).
1150 -- Set True when the component is a nested composite, and it does not
1151 -- have the same scalar storage order as Encl_Type.
1155 begin
1156 -- Record case
1166 else
1167 -- If a component clause is present, check if the component starts
1168 -- on a storage element boundary. Otherwise conservatively assume
1169 -- it does so only in the case where the record is not packed.
1172 Comp_Byte_Aligned :=
1174 else
1181 -- Array case
1183 else
1190 -- Note: the Reverse_Storage_Order flag is set on the base type, but
1191 -- the attribute definition clause is attached to the first subtype.
1194 Comp_ADC := Get_Attribute_Definition_Clause
1196 Attribute_Scalar_Storage_Order);
1199 -- Case of record or array component: check storage order compatibility
1202 Comp_SSO_Differs :=
1204 /=
1207 -- Parent and extension must have same storage order
1211 Error_Msg_N
1216 -- If enclosing composite has explicit SSO then nested composite must
1217 -- have explicit SSO as well.
1223 -- If component and composite SSO differs, check that component
1224 -- falls on byte boundaries and isn't packed.
1228 -- Component SSO differs from enclosing composite:
1230 -- Reject if component is a packed array, as it may be represented
1231 -- as a scalar internally.
1234 Error_Msg_N
1238 -- Reject if composite is a packed array, as it may be rewritten
1239 -- into an array of scalars.
1245 -- Reject if not byte aligned
1248 and then not Comp_Byte_Aligned
1249 then
1250 Error_Msg_N
1256 -- Enclosing type has explicit SSO: non-composite component must not
1257 -- be aliased.
1260 Error_Msg_N
1266 -----------------------------
1267 -- Check_Debug_Info_Needed --
1268 -----------------------------
1271 begin
1276 or else Debug_Generated_Code
1277 or else Debug_Flag_VV
1279 then
1284 -------------------------------
1285 -- Check_Expression_Function --
1286 -------------------------------
1292 -- Function to search for deferred constant
1294 -------------------
1295 -- Find_Constant --
1296 -------------------
1299 begin
1300 -- When a constant is initialized with the result of a dispatching
1301 -- call, the constant declaration is rewritten as a renaming of the
1302 -- displaced function result. This scenario is not a premature use of
1303 -- a constant even though the Has_Completion flag is not set.
1310 N_Object_Declaration
1313 then
1314 Error_Msg_NE
1322 then
1332 -- Start of processing for Check_Expression_Function
1334 begin
1339 then
1344 ----------------------------
1345 -- Check_Strict_Alignment --
1346 ----------------------------
1351 begin
1369 then
1379 -------------------------
1380 -- Check_Unsigned_Type --
1381 -------------------------
1388 begin
1393 -- Do not attempt to analyze case where range was in error
1399 -- The situation that is non trivial is something like
1401 -- subtype x1 is integer range -10 .. +10;
1402 -- subtype x2 is x1 range 0 .. V1;
1403 -- subtype x3 is x2 range V2 .. V3;
1404 -- subtype x4 is x3 range V4 .. V5;
1406 -- where Vn are variables. Here the base type is signed, but we still
1407 -- know that x4 is unsigned because of the lower bound of x2.
1409 -- The only way to deal with this is to look up the ancestor chain
1412 loop
1426 else
1429 -- If no ancestor had a static lower bound, go to base type
1433 -- Note: the reason we still check for a compile time known
1434 -- value for the base type is that at least in the case of
1435 -- generic formals, we can have bounds that fail this test,
1436 -- and there may be other cases in error situations.
1448 then
1458 -----------------------------
1459 -- Is_Atomic_VFA_Aggregate --
1460 -----------------------------
1469 begin
1472 -- Array may be qualified, so find outer context
1489 then
1498 then
1507 New_N :=
1519 -----------------------------------------------
1520 -- Explode_Initialization_Compound_Statement --
1521 -----------------------------------------------
1526 begin
1529 then
1532 -- Note that we rewrite Init_Stmts into a NULL statement, rather than
1533 -- just removing it, because Freeze_All may rely on this particular
1534 -- Node_Id still being present in the enclosing list to know where to
1535 -- stop freezing.
1543 ----------------
1544 -- Freeze_All --
1545 ----------------
1547 -- Note: the easy coding for this procedure would be to just build a
1548 -- single list of freeze nodes and then insert them and analyze them
1549 -- all at once. This won't work, because the analysis of earlier freeze
1550 -- nodes may recursively freeze types which would otherwise appear later
1551 -- on in the freeze list. So we must analyze and expand the freeze nodes
1552 -- as they are generated.
1559 -- This is the internal recursive routine that does freezing of entities
1560 -- (but NOT the analysis of default expressions, which should not be
1561 -- recursive, we don't want to analyze those till we are sure that ALL
1562 -- the types are frozen).
1564 --------------------
1565 -- Freeze_All_Ent --
1566 --------------------
1574 -- If freeze nodes are present, insert and analyze, and reset cursor
1575 -- for next insertion.
1577 -------------------
1578 -- Process_Flist --
1579 -------------------
1582 begin
1589 else
1595 -- Start or processing for Freeze_All_Ent
1597 begin
1601 -- If the entity is an inner package which is not a package
1602 -- renaming, then its entities must be frozen at this point. Note
1603 -- that such entities do NOT get frozen at the end of the nested
1604 -- package itself (only library packages freeze).
1606 -- Same is true for task declarations, where anonymous records
1607 -- created for entry parameters must be frozen.
1613 then
1624 then
1631 N_Single_Task_Declaration)
1632 then
1635 End_Scope;
1637 -- For a derived tagged type, we must ensure that all the
1638 -- primitive operations of the parent have been frozen, so that
1639 -- their addresses will be in the parent's dispatch table at the
1640 -- point it is inherited.
1646 then
1647 declare
1654 begin
1661 then
1663 Process_Flist;
1673 Process_Flist;
1675 -- If already frozen, and there are delayed aspects, this is where
1676 -- we do the visibility check for these aspects (see Sem_Ch13 spec
1677 -- for a description of how we handle aspect visibility).
1681 -- Retrieve the visibility to the discriminants in order to
1682 -- analyze properly the aspects.
1686 declare
1689 begin
1695 then
1706 -- If an incomplete type is still not frozen, this may be a
1707 -- premature freezing because of a body declaration that follows.
1708 -- Indicate where the freezing took place. Freezing will happen
1709 -- if the body comes from source, but not if it is internally
1710 -- generated, for example as the body of a type invariant.
1712 -- If the freezing is caused by the end of the current declarative
1713 -- part, it is a Taft Amendment type, and there is no error.
1717 then
1718 declare
1721 begin
1722 -- The presence of a body freezes all entities previously
1723 -- declared in the current list of declarations, but this
1724 -- does not apply if the body does not come from source.
1725 -- A type invariant is transformed into a subprogram body
1726 -- which is placed at the end of the private part of the
1727 -- current package, but this body does not freeze incomplete
1728 -- types that may be declared in this private part.
1731 N_Entry_Body,
1732 N_Package_Body,
1733 N_Protected_Body,
1734 N_Task_Body)
1736 and then
1739 then
1741 Error_Msg_NE
1752 -- Start of processing for Freeze_All
1754 begin
1757 -- Now that all types are frozen, we can deal with default expressions
1758 -- that require us to build a default expression functions. This is the
1759 -- point at which such functions are constructed (after all types that
1760 -- might be used in such expressions have been frozen).
1762 -- For subprograms that are renaming_as_body, we create the wrapper
1763 -- bodies as needed.
1765 -- We also add finalization chains to access types whose designated
1766 -- types are controlled. This is normally done when freezing the type,
1767 -- but this misses recursive type definitions where the later members
1768 -- of the recursion introduce controlled components.
1770 -- Loop through entities
1785 else
1791 and then
1793 = N_Subprogram_Renaming_Declaration
1794 then
1795 Build_And_Analyze_Renamed_Body
1802 N_Single_Task_Declaration)
1803 then
1804 declare
1807 begin
1812 then
1821 -- Historical note: We used to create a finalization master for an
1822 -- access type whose designated type is not controlled, but contains
1823 -- private controlled compoments. This form of postprocessing is no
1824 -- longer needed because the finalization master is now created when
1825 -- the access type is frozen (see Exp_Ch3.Freeze_Type).
1831 -----------------------
1832 -- Freeze_And_Append --
1833 -----------------------
1835 procedure Freeze_And_Append
1839 is
1841 begin
1845 else
1851 -------------------
1852 -- Freeze_Before --
1853 -------------------
1858 begin
1868 -------------------
1869 -- Freeze_Entity --
1870 -------------------
1874 -- Save the current Ghost mode in effect in case the entity being frozen
1875 -- sets a different mode.
1885 -- This flag gets set to true for a variable with default initialization
1888 -- Used to detect attempt to freeze function declared in another unit
1891 -- List of freezing actions, left at No_List if none
1894 -- This could use a comment ???
1897 -- N is a freezing action to be appended to the Result
1900 -- If Loc is a freeze_entity that appears after the last declaration
1901 -- in the scope, inhibit error messages on late completion.
1904 -- Check that an Access or Unchecked_Access attribute with a prefix
1905 -- which is the current instance type can only be applied when the type
1906 -- is limited.
1909 -- Give warning for modulus of 8, 16, 32, or 64 given as an explicit
1910 -- integer literal without an explicit corresponding size clause. The
1911 -- caller has checked that Utype is a modular integer type.
1914 -- Freeze array type, including freezing index and component types
1917 -- Perform checks and generate freeze node if needed for a constant or
1918 -- variable declared by an object declaration.
1921 -- Create Freeze_Generic_Entity nodes for types declared in a generic
1922 -- package. Recurse on inner generic packages.
1925 -- Freeze formals and return type of subprogram. If some type in the
1926 -- profile is a limited view, freezing of the entity will take place
1927 -- elsewhere, and the function returns False. This routine will be
1928 -- modified if and when we can implement AI05-019 efficiently ???
1931 -- Freeze record type, including freezing component types, and freezing
1932 -- primitive operations if this is a tagged type.
1935 -- Determine whether an arbitrary entity is subject to Boolean aspect
1936 -- Import and its value is specified as True.
1939 -- Following AI05-151, a function can return a limited view of a type
1940 -- declared elsewhere. In that case the function cannot be frozen at
1941 -- the end of its enclosing package. If its first use is in a different
1942 -- unit, it cannot be frozen there, but if the call is legal the full
1943 -- view of the return type is available and the subprogram can now be
1944 -- frozen. However the freeze node cannot be inserted at the point of
1945 -- call, but rather must go in the package holding the function, so that
1946 -- the backend can process it in the proper context.
1949 -- Restore the values of all saved global variables
1952 -- If E is an entity for an imported subprogram with pre/post-conditions
1953 -- then this procedure will create a wrapper to ensure that proper run-
1954 -- time checking of the pre/postconditions. See body for details.
1956 -------------------
1957 -- Add_To_Result --
1958 -------------------
1961 begin
1964 else
1969 ----------------------------
1970 -- After_Last_Declaration --
1971 ----------------------------
1976 begin
1982 else
1986 else
1991 ----------------------------
1992 -- Check_Current_Instance --
1993 ----------------------------
1998 -- Determine whether Typ is compatible with the rules for aliased
1999 -- views of types as defined in RM 3.10 in the various dialects.
2002 -- Process routine to apply check to given node
2004 -----------------------------
2005 -- Is_Aliased_View_Of_Type --
2006 -----------------------------
2011 begin
2012 -- Common case
2016 then
2019 -- The following paragraphs describe what a legal aliased view of
2020 -- a type is in the various dialects of Ada.
2022 -- Ada 95
2024 -- The current instance of a limited type, and a formal parameter
2025 -- or generic formal object of a tagged type.
2027 -- Ada 95 limited type
2028 -- * Type with reserved word "limited"
2029 -- * A protected or task type
2030 -- * A composite type with limited component
2035 -- Ada 2005
2037 -- The current instance of a limited tagged type, a protected
2038 -- type, a task type, or a type that has the reserved word
2039 -- "limited" in its full definition ... a formal parameter or
2040 -- generic formal object of a tagged type.
2042 -- Ada 2005 limited type
2043 -- * Type with reserved word "limited", "synchronized", "task"
2044 -- or "protected"
2045 -- * A composite type with limited component
2046 -- * A derived type whose parent is a non-interface limited type
2049 return
2051 or else
2056 -- Ada 2012 and beyond
2058 -- The current instance of an immutably limited type ... a formal
2059 -- parameter or generic formal object of a tagged type.
2061 -- Ada 2012 limited type
2062 -- * Type with reserved word "limited", "synchronized", "task"
2063 -- or "protected"
2064 -- * A composite type with limited component
2065 -- * A derived type whose parent is a non-interface limited type
2066 -- * An incomplete view
2068 -- Ada 2012 immutably limited type
2069 -- * Explicitly limited record type
2070 -- * Record extension with "limited" present
2071 -- * Non-formal limited private type that is either tagged
2072 -- or has at least one access discriminant with a default
2073 -- expression
2074 -- * Task type, protected type or synchronized interface
2075 -- * Type derived from immutably limited type
2077 else
2078 return
2084 -------------
2085 -- Process --
2086 -------------
2089 begin
2093 Name_Unchecked_Access)
2097 then
2099 Error_Msg_N
2102 else
2103 Error_Msg_N
2110 else
2120 -- Local variables
2125 -- Start of processing for Check_Current_Instance
2127 begin
2133 ------------------------------
2134 -- Check_Suspicious_Modulus --
2135 ------------------------------
2140 begin
2146 declare
2149 begin
2151 declare
2155 begin
2157 declare
2161 begin
2162 -- First case, modulus and size are the same. This
2163 -- happens if you have something like mod 32, with
2164 -- an explicit size of 32, this is for sure a case
2165 -- where the warning is given, since it is seems
2166 -- very unlikely that someone would want e.g. a
2167 -- five bit type stored in 32 bits. It is much
2168 -- more likely they wanted a 32-bit type.
2173 -- Second case, the modulus is 32 or 64 and no
2174 -- size clause is present. This is a less clear
2175 -- case for giving the warning, but in the case
2176 -- of 32/64 (5-bit or 6-bit types) these seem rare
2177 -- enough that it is a likely error (and in any
2178 -- case using 2**5 or 2**6 in these cases seems
2179 -- clearer. We don't include 8 or 16 here, simply
2180 -- because in practice 3-bit and 4-bit types are
2181 -- more common and too many false positives if
2182 -- we warn in these cases.
2186 then
2189 -- No warning needed
2191 else
2195 -- If we fall through, give warning
2198 Error_Msg_N
2200 Modulus);
2209 -----------------------
2210 -- Freeze_Array_Type --
2211 -----------------------
2219 -- Set true if any of the index types is an enumeration type with a
2220 -- non-standard representation.
2222 begin
2231 then
2238 -- Processing that is done only for base types
2242 -- Deal with default setting of reverse storage order
2246 -- Propagate flags for component type
2250 then
2258 -- Warn for pragma Pack overriding foreign convention
2262 then
2263 declare
2268 begin
2272 Error_Msg_N
2275 Error_Msg_N
2282 -- If packing was requested or if the component size was
2283 -- set explicitly, then see if bit packing is required. This
2284 -- processing is only done for base types, since all of the
2285 -- representation aspects involved are type-related.
2287 -- This is not just an optimization, if we start processing the
2288 -- subtypes, they interfere with the settings on the base type
2289 -- (this is because Is_Packed has a slightly different meaning
2290 -- before and after freezing).
2292 declare
2296 begin
2300 then
2309 else
2312 -- We can set the component size if it is less than 16,
2313 -- rounding it up to the next storage unit size.
2319 else
2323 -- Set component size up to match alignment if it would
2324 -- otherwise be less than the alignment. This deals with
2325 -- cases of types whose alignment exceeds their size (the
2326 -- padded type cases).
2329 declare
2331 begin
2339 -- Case of component size that may result in packing
2342 declare
2348 Get_Attribute_Definition_Clause
2351 begin
2352 -- Warn if we have pack and component size so that the
2353 -- pack is ignored.
2355 -- Note: here we must check for the presence of a
2356 -- component size before checking for a Pack pragma to
2357 -- deal with the case where the array type is a derived
2358 -- type whose parent is currently private.
2362 and then Warn_On_Redundant_Constructs
2363 then
2365 Error_Msg_NE
2367 Error_Msg_N
2373 -- Set component size if not already set by a component
2374 -- size clause.
2380 -- Check for base type of 8, 16, 32 bits, where an
2381 -- unsigned subtype has a length one less than the
2382 -- base type (e.g. Natural subtype of Integer).
2384 -- In such cases, if a component size was not set
2385 -- explicitly, then generate a warning.
2391 then
2395 Error_Msg_N
2397 Pack_Pragma);
2398 Error_Msg_N
2400 Pack_Pragma);
2404 -- Actual packing is not needed for 8, 16, 32, 64. Also
2405 -- not needed for 24 if alignment is 1.
2412 then
2413 -- Here the array was requested to be packed, but
2414 -- the packing request had no effect, so Is_Packed
2415 -- is reset.
2417 -- Note: semantically this means that we lose track
2418 -- of the fact that a derived type inherited a pragma
2419 -- Pack that was non- effective, but that seems fine.
2421 -- We regard a Pack pragma as a request to set a
2422 -- representation characteristic, and this request
2423 -- may be ignored.
2430 then
2434 -- In all other cases, packing is indeed needed
2436 else
2445 -- Check for Aliased or Atomic_Components/Atomic/VFA with
2446 -- unsuitable packing or explicit component size clause given.
2451 and then
2453 then
2457 -- Outputs error messages for incorrect CS clause or pragma
2458 -- Pack for aliased or atomic/VFA components (T is "aliased"
2459 -- or "atomic/vfa");
2461 -----------------
2462 -- Complain_CS --
2463 -----------------
2466 begin
2468 Clause :=
2469 Get_Attribute_Definition_Clause
2472 Error_Msg_N
2476 Error_Msg_N
2479 else
2480 Error_Msg_N
2486 -- Start of processing for Alias_Atomic_Check
2488 begin
2489 -- If object size of component type isn't known, we cannot
2490 -- be sure so we defer to the back end.
2495 -- Case where component size has no effect. First check for
2496 -- object size of component type multiple of the storage
2497 -- unit size.
2501 -- OK in both packing case and component size case if RM
2502 -- size is known and static and same as the object size.
2504 and then
2508 -- Or if we have an explicit component size clause and
2509 -- the component size and object size are equal.
2511 or else
2514 then
2522 then
2531 -- Check for Independent_Components/Independent with unsuitable
2532 -- packing or explicit component size clause given.
2535 and then
2537 then
2538 begin
2539 -- If object size of component type isn't known, we cannot
2540 -- be sure so we defer to the back end.
2545 -- Case where component size has no effect. First check for
2546 -- object size of component type multiple of the storage
2547 -- unit size.
2551 -- OK in both packing case and component size case if RM
2552 -- size is known and multiple of the storage unit size.
2554 and then
2558 -- Or if we have an explicit component size clause and
2559 -- the component size is larger than the object size.
2561 or else
2564 then
2567 else
2569 Clause :=
2570 Get_Attribute_Definition_Clause
2573 Error_Msg_N
2577 Error_Msg_N
2580 else
2581 Error_Msg_N
2589 -- Warn for case of atomic type
2595 then
2596 Error_Msg_NE
2611 -- Check for scalar storage order
2613 declare
2615 begin
2616 Check_Component_Storage_Order
2619 ADC => Get_Attribute_Definition_Clause
2621 Attribute_Scalar_Storage_Order),
2625 -- Processing that is done only for subtypes
2627 else
2628 -- Acquire alignment from base type
2636 -- Specific checks for bit-packed arrays
2640 -- Check number of elements for bit packed arrays that come from
2641 -- source and have compile time known ranges. The bit-packed
2642 -- arrays circuitry does not support arrays with more than
2643 -- Integer'Last + 1 elements, and when this restriction is
2644 -- violated, causes incorrect data access.
2646 -- For the case where this is not compile time known, a run-time
2647 -- check should be generated???
2650 declare
2656 begin
2662 -- Never generate an error if any index is of a generic
2663 -- type. We will check this in instances.
2670 Ilen :=
2676 -- No attempt is made to check number of elements if not
2677 -- compile time known.
2690 then
2691 Error_Msg_N
2698 -- Check size
2701 declare
2705 begin
2706 -- It is not clear if it is possible to have no size clause
2707 -- at this stage, but it is not worth worrying about. Post
2708 -- error on the entity name in the size clause if present,
2709 -- else on the type entity itself.
2713 else
2720 -- If any of the index types was an enumeration type with a non-
2721 -- standard rep clause, then we indicate that the array type is
2722 -- always packed (even if it is not bit packed).
2731 -- If the array is packed, we must create the packed array type to be
2732 -- used to actually implement the type. This is only needed for real
2733 -- array types (not for string literal types, since they are present
2734 -- only for the front end).
2738 then
2742 -- Make sure that we have the necessary routines to implement the
2743 -- packing, and complain now if not. Note that we only test this
2744 -- for constrained array types.
2750 then
2751 declare
2755 begin
2758 then
2759 Error_Msg_CRT
2763 -- Cancel the packing
2773 -- Size information of packed array type is copied to the array
2774 -- type, since this is really the representation. But do not
2775 -- override explicit existing size values. If the ancestor subtype
2776 -- is constrained the Packed_Array_Impl_Type will be inherited
2777 -- from it, but the size may have been provided already, and
2778 -- must not be overridden either.
2781 and then
2784 then
2796 -- For non-packed arrays set the alignment of the array to the
2797 -- alignment of the component type if it is unknown. Skip this
2798 -- in atomic/VFA case (atomic/VFA arrays may need larger alignments).
2807 then
2812 -------------------------------
2813 -- Freeze_Object_Declaration --
2814 -------------------------------
2817 begin
2818 -- Abstract type allowed only for C++ imported variables or constants
2820 -- Note: we inhibit this check for objects that do not come from
2821 -- source because there is at least one case (the expansion of
2822 -- x'Class'Input where x is abstract) where we legitimately
2823 -- generate an abstract object.
2828 then
2833 Error_Msg_NE
2838 Error_Msg_N -- CODEFIX
2844 -- For object created by object declaration, perform required
2845 -- categorization (preelaborate and pure) checks. Defer these
2846 -- checks to freeze time since pragma Import inhibits default
2847 -- initialization and thus pragma Import affects these checks.
2851 -- If there is an address clause, check that it is valid
2852 -- and if need be move initialization to the freeze node.
2856 -- Similar processing is needed for aspects that may affect
2857 -- object layout, like Alignment, if there is an initialization
2858 -- expression.
2861 and then Expander_Active
2864 then
2865 declare
2869 begin
2871 -- Capture initialization value at point of declaration, and
2872 -- make explicit assignment legal, because object may be a
2873 -- constant.
2878 -- Move initialization to freeze actions.
2886 -- Set_Is_Frozen (E, False);
2890 -- Reset Is_True_Constant for non-constant aliased object. We
2891 -- consider that the fact that a non-constant object is aliased may
2892 -- indicate that some funny business is going on, e.g. an aliased
2893 -- object is passed by reference to a procedure which captures the
2894 -- address of the object, which is later used to assign a new value,
2895 -- even though the compiler thinks that it is not modified. Such
2896 -- code is highly dubious, but we choose to make it "work" for
2897 -- non-constant aliased objects.
2899 -- Note that we used to do this for all aliased objects, whether or
2900 -- not constant, but this caused anomalies down the line because we
2901 -- ended up with static objects that were not Is_True_Constant. Not
2902 -- resetting Is_True_Constant for (aliased) constant objects ensures
2903 -- that this anomaly never occurs.
2905 -- However, we don't do that for internal entities. We figure that if
2906 -- we deliberately set Is_True_Constant for an internal entity, e.g.
2907 -- a dispatch table entry, then we mean it.
2912 then
2916 -- If the object needs any kind of default initialization, an error
2917 -- must be issued if No_Default_Initialization applies. The check
2918 -- doesn't apply to imported objects, which are not ever default
2919 -- initialized, and is why the check is deferred until freezing, at
2920 -- which point we know if Import applies. Deferred constants are also
2921 -- exempted from this test because their completion is explicit, or
2922 -- through an import pragma.
2930 and then
2935 or else
2938 then
2940 Check_Restriction
2944 -- Check that a Thread_Local_Storage variable does not have
2945 -- default initialization, and any explicit initialization must
2946 -- either be the null constant or a static constant.
2949 declare
2951 begin
2952 if Has_Default_Initialization
2953 or else
2955 and then
2957 or else not
2960 then
2961 Error_Msg_NE
2964 Error_Msg_NE
2971 -- For imported objects, set Is_Public unless there is also an
2972 -- address clause, which means that there is no external symbol
2973 -- needed for the Import (Is_Public may still be set for other
2974 -- unrelated reasons). Note that we delayed this processing
2975 -- till freeze time so that we can be sure not to set the flag
2976 -- if there is an address clause. If there is such a clause,
2977 -- then the only purpose of the Import pragma is to suppress
2978 -- implicit initialization.
2984 -- For source objects that are not Imported and are library
2985 -- level, if no linker section pragma was given inherit the
2986 -- appropriate linker section from the corresponding type.
2992 then
2993 Set_Linker_Section_Pragma
2997 -- For convention C objects of an enumeration type, warn if the
2998 -- size is not integer size and no explicit size given. Skip
2999 -- warning for Boolean, and Character, assume programmer expects
3000 -- 8-bit sizes for these cases.
3003 or else
3010 then
3012 Error_Msg_N
3018 -----------------------------
3019 -- Freeze_Generic_Entities --
3020 -----------------------------
3027 begin
3046 --------------------
3047 -- Freeze_Profile --
3048 --------------------
3055 begin
3056 -- Loop through formals
3062 -- AI05-0151: incomplete types can appear in a profile. By the
3063 -- time the entity is frozen, the full view must be available,
3064 -- unless it is a limited view.
3069 then
3083 then
3084 -- If the type of a formal is incomplete, subprogram is being
3085 -- frozen prematurely. Within an instance (but not within a
3086 -- wrapper package) this is an artifact of our need to regard
3087 -- the end of an instantiation as a freeze point. Otherwise it
3088 -- is a definite error.
3095 elsif not After_Last_Declaration
3096 and then not Freezing_Library_Level_Tagged_Type
3097 then
3099 Error_Msg
3104 -- Check suspicious parameter for C function. These tests apply
3105 -- only to exported/imported subprograms.
3107 if Warn_On_Export_Import
3110 or else
3117 then
3118 -- Qualify mention of formals with subprogram name
3122 -- Check suspicious use of fat C pointer
3126 then
3127 Error_Msg_N
3130 -- Check suspicious return of boolean
3137 then
3138 Error_Msg_N
3140 Error_Msg_N
3144 -- Check suspicious tagged type
3147 or else
3151 then
3152 Error_Msg_N
3156 -- Check wrong convention subprogram pointer
3160 then
3161 Error_Msg_N
3165 Error_Msg_NE
3170 -- Turn off name qualification after message output
3175 -- Check for unconstrained array in exported foreign convention
3176 -- case.
3182 and then Warn_On_Export_Import
3184 -- Exclude VM case, since both .NET and JVM can handle
3185 -- unconstrained arrays without a problem.
3188 then
3191 -- If this is an inherited operation, place the warning on
3192 -- the derived type declaration, rather than on the original
3193 -- subprogram.
3196 then
3202 else
3218 -- If the formal is an anonymous_access_to_subprogram
3219 -- freeze the subprogram type as well, to prevent
3220 -- scope anomalies in gigi, because there is no other
3221 -- clear point at which it could be frozen.
3225 then
3233 -- Case of function: similar checks on return type
3237 -- Check whether function is declared elsewhere.
3239 Late_Freezing :=
3244 -- Freeze return type
3248 -- AI05-0151: the return type may have been incomplete
3249 -- at the point of declaration. Replace it with the full
3250 -- view, unless the current type is a limited view. In
3251 -- that case the full view is in a different unit, and
3252 -- gigi finds the non-limited view after the other unit
3253 -- is elaborated.
3258 then
3262 -- If the return type is a limited view and the non-limited
3263 -- view is still incomplete, the function has to be frozen at a
3264 -- later time. If the function is abstract there is no place at
3265 -- which the full view will become available, and no code to be
3266 -- generated for it, so mark type as frozen.
3271 then
3274 else
3283 -- Check suspicious return type for C function
3285 if Warn_On_Export_Import
3287 or else
3290 then
3291 -- Check suspicious return of fat C pointer
3297 then
3301 -- Check suspicious return of boolean
3309 then
3310 declare
3313 begin
3314 Error_Msg_NE
3316 Error_Msg_NE
3321 -- Check suspicious return tagged type
3325 and then
3326 Is_Tagged_Type
3331 then
3335 -- Check return of wrong convention subprogram pointer
3341 then
3345 Error_Msg_NE
3351 -- Give warning for suspicious return of a result of an
3352 -- unconstrained array type in a foreign convention function.
3356 -- We are looking for a return of unconstrained array
3361 -- Exclude imported routines, the warning does not belong on
3362 -- the import, but rather on the routine definition.
3366 -- Exclude VM case, since both .NET and JVM can handle return
3367 -- of unconstrained arrays without a problem.
3371 -- Check that general warning is enabled, and that it is not
3372 -- suppressed for this particular case.
3374 and then Warn_On_Export_Import
3377 then
3383 -- Check suspicious use of Import in pure unit (cases where the RM
3384 -- allows calls to be omitted).
3388 -- It might be suspicious if the compilation unit has the Pure
3389 -- aspect/pragma.
3393 -- The RM allows omission of calls only in the case of
3394 -- library-level subprograms (see RM-10.2.1(18)).
3398 -- Ignore internally generated entity. This happens in some cases
3399 -- of subprograms in specs, where we generate an implied body.
3403 -- Assume run-time knows what it is doing
3405 and then not GNAT_Mode
3407 -- Assume explicit Pure_Function means import is pure
3411 -- Don't need warning in relaxed semantics mode
3413 and then not Relaxed_RM_Semantics
3415 -- Assume convention Intrinsic is OK, since this is specialized.
3416 -- This deals with the DEC unit current_exception.ads
3420 -- Assume that ASM interface knows what it is doing. This deals
3421 -- with unsigned.ads in the AAMP back end.
3424 then
3425 Error_Msg_N
3427 Error_Msg_NE
3435 ------------------------
3436 -- Freeze_Record_Type --
3437 ------------------------
3449 -- Set True if the record type scope Rec has been pushed on the scope
3450 -- stack. Needed for the analysis of delayed aspects specified to the
3451 -- components of Rec.
3454 -- Scalar_Storage_Order attribute definition clause for the record
3457 -- Set True if we find at least one component with no component
3458 -- clause (used to warn about useless Pack pragmas).
3461 -- Set True if we find at least one component with a component
3462 -- clause (used to warn about useless Bit_Order pragmas, and also
3463 -- to detect cases where Implicit_Packing may have an effect).
3466 -- Set True if we find at least one component which is aliased. This
3467 -- is used to prevent Implicit_Packing of the record, since packing
3468 -- cannot modify the size of alignment of an aliased component.
3471 -- Set True if we find at least one component whose type has a
3472 -- Scalar_Storage_Order attribute definition clause.
3475 -- Set False if we encounter a component of a non-scalar type
3479 -- Accumulates total RM_Size values and total Esize values of all
3480 -- scalar components. Used for processing of Implicit_Packing.
3483 -- If N is an allocator, possibly wrapped in one or more level of
3484 -- qualified expression(s), return the inner allocator node, else
3485 -- return Empty.
3488 -- If the component subtype is an access to a constrained subtype of
3489 -- an already frozen type, make the subtype frozen as well. It might
3490 -- otherwise be frozen in the wrong scope, and a freeze node on
3491 -- subtype has no effect. Similarly, if the component subtype is a
3492 -- regular (not protected) access to subprogram, set the anonymous
3493 -- subprogram type to frozen as well, to prevent an out-of-scope
3494 -- freeze node at some eventual point of call. Protected operations
3495 -- are handled elsewhere.
3498 -- Make sure that all types mentioned in Discrete_Choices of the
3499 -- variants referenceed by the Variant_Part VP are frozen. This is
3500 -- a recursive routine to deal with nested variants.
3502 ---------------------
3503 -- Check_Allocator --
3504 ---------------------
3508 begin
3510 loop
3515 else
3521 -----------------
3522 -- Check_Itype --
3523 -----------------
3528 begin
3531 then
3534 -- In addition, add an Itype_Reference to ensure that the
3535 -- access subtype is elaborated early enough. This cannot be
3536 -- done if the subtype may depend on discriminants.
3541 then
3549 then
3554 ------------------------------------
3555 -- Freeze_Choices_In_Variant_Part --
3556 ------------------------------------
3565 begin
3566 -- Loop through variants
3571 -- Loop through choices, checking that all types are frozen
3577 then
3584 -- Check for nested variant part to process
3598 -- Start of processing for Freeze_Record_Type
3600 begin
3601 -- Deal with delayed aspect specifications for components. The
3602 -- analysis of the aspect is required to be delayed to the freeze
3603 -- point, thus we analyze the pragma or attribute definition
3604 -- clause in the tree at this point. We also analyze the aspect
3605 -- specification node at the freeze point when the aspect doesn't
3606 -- correspond to pragma/attribute definition clause.
3612 then
3617 -- The visibility to the discriminants must be restored in
3618 -- order to properly analyze the aspects.
3631 -- Pop the scope if Rec scope has been pushed on the scope stack
3632 -- during the delayed aspect analysis process.
3639 Pop_Scope;
3642 -- Freeze components and embedded subtypes
3651 -- Handle the component and discriminant case
3654 declare
3657 begin
3658 -- Freezing a record type freezes the type of each of its
3659 -- components. However, if the type of the component is
3660 -- part of this record, we do not want or need a separate
3661 -- Freeze_Node. Note that Is_Itype is wrong because that's
3662 -- also set in private type cases. We also can't check for
3663 -- the Scope being exactly Rec because of private types and
3664 -- record extensions.
3669 then
3675 -- Warn for pragma Pack overriding foreign convention
3680 -- Don't warn for aliased components, since override
3681 -- cannot happen in that case.
3684 then
3685 declare
3690 begin
3694 Error_Msg_N
3696 PP);
3698 Error_Msg_NE
3705 -- Check for error of component clause given for variable
3706 -- sized type. We have to delay this test till this point,
3707 -- since the component type has to be frozen for us to know
3708 -- if it is variable length.
3713 -- We omit this test in a generic context, it will be
3714 -- applied at instantiation time.
3719 -- Also omit this test in CodePeer mode, since we do not
3720 -- have sufficient info on size and rep clauses.
3725 -- Omit check if component has a generic type. This can
3726 -- happen in an instantiation within a generic in ASIS
3727 -- mode, where we force freeze actions without full
3728 -- expansion.
3733 -- Do the check
3735 elsif not
3736 Size_Known_At_Compile_Time
3738 then
3739 Error_Msg_N
3744 else
3748 -- Case of component requires byte alignment
3752 -- Set the enclosing record to also require byte align
3756 -- Check for component clause that is inconsistent with
3757 -- the required byte boundary alignment.
3762 then
3763 Error_Msg_N
3771 -- Gather data for possible Implicit_Packing later. Note that at
3772 -- this stage we might be dealing with a real component, or with
3773 -- an implicit subtype declaration.
3777 else
3778 Scalar_Component_Total_RM_Size :=
3780 Scalar_Component_Total_Esize :=
3784 -- If the component is an Itype with Delayed_Freeze and is either
3785 -- a record or array subtype and its base type has not yet been
3786 -- frozen, we must remove this from the entity list of this record
3787 -- and put it on the entity list of the scope of its base type.
3788 -- Note that we know that this is not the type of a component
3789 -- since we cleared Has_Delayed_Freeze for it in the previous
3790 -- loop. Thus this must be the Designated_Type of an access type,
3791 -- which is the type of a component.
3799 then
3800 declare
3804 begin
3805 -- We have a difficult case to handle here. Suppose Rec is
3806 -- subtype being defined in a subprogram that's created as
3807 -- part of the freezing of Rec'Base. In that case, we know
3808 -- that Comp'Base must have already been frozen by the time
3809 -- we get to elaborate this because Gigi doesn't elaborate
3810 -- any bodies until it has elaborated all of the declarative
3811 -- part. But Is_Frozen will not be set at this point because
3812 -- we are processing code in lexical order.
3814 -- We detect this case by going up the Scope chain of Rec
3815 -- and seeing if we have a subprogram scope before reaching
3816 -- the top of the scope chain or that of Comp'Base. If we
3817 -- do, then mark that Comp'Base will actually be frozen. If
3818 -- so, we merely undelay it.
3835 else
3838 else
3842 -- Insert in entity list of scope of base type (which
3843 -- must be an enclosing scope, because still unfrozen).
3849 -- If the component is an access type with an allocator as default
3850 -- value, the designated type will be frozen by the corresponding
3851 -- expression in init_proc. In order to place the freeze node for
3852 -- the designated type before that for the current record type,
3853 -- freeze it now.
3855 -- Same process if the component is an array of access types,
3856 -- initialized with an aggregate. If the designated type is
3857 -- private, it cannot contain allocators, and it is premature
3858 -- to freeze the type, so we check for this as well.
3863 then
3864 declare
3868 begin
3871 -- If component is pointer to a class-wide type, freeze
3872 -- the specific type in the expression being allocated.
3873 -- The expression may be a subtype indication, in which
3874 -- case freeze the subtype mark.
3876 if Is_Class_Wide_Type
3878 then
3880 Freeze_And_Append
3884 then
3885 Freeze_And_Append
3893 else
3894 Freeze_And_Append
3902 then
3905 -- Freeze the designated type when initializing a component with
3906 -- an aggregate in case the aggregate contains allocators.
3908 -- type T is ...;
3909 -- type T_Ptr is access all T;
3910 -- type T_Array is array ... of T_Ptr;
3912 -- type Rec is record
3913 -- Comp : T_Array := (others => ...);
3914 -- end record;
3918 then
3919 declare
3922 Designated_Type
3925 begin
3926 -- The only case when this sort of freezing is not done is
3927 -- when the designated type is class-wide and the root type
3928 -- is the record owning the component. This scenario results
3929 -- in a circularity because the class-wide type requires
3930 -- primitives that have not been created yet as the root
3931 -- type is in the process of being frozen.
3933 -- type Rec is tagged;
3934 -- type Rec_Ptr is access all Rec'Class;
3935 -- type Rec_Array is array ... of Rec_Ptr;
3937 -- type Rec is record
3938 -- Comp : Rec_Array := (others => ...);
3939 -- end record;
3943 then
3951 then
3961 -- Deal with default setting of reverse storage order
3965 -- Check consistent attribute setting on component types
3967 SSO_ADC := Get_Attribute_Definition_Clause
3970 declare
3972 begin
3975 Check_Component_Storage_Order
3985 -- Now deal with reverse storage order/bit order issues
3989 -- Check compatibility of Scalar_Storage_Order with Bit_Order, if
3990 -- the former is specified.
3994 -- Note: report error on Rec, not on SSO_ADC, as ADC may apply
3995 -- to some ancestor type.
3998 Error_Msg_N
4003 -- Warn if there is an Scalar_Storage_Order attribute definition
4004 -- clause but no component clause, no component that itself has
4005 -- such an attribute definition, and no pragma Pack.
4008 or else
4009 SSO_ADC_Component
4010 or else
4012 then
4013 Error_Msg_N
4015 SSO_ADC);
4019 -- Deal with Bit_Order aspect
4027 then
4028 -- Warn if clause has no effect when no component clause is
4029 -- present, but suppress warning if the Bit_Order is required
4030 -- due to the presence of a Scalar_Storage_Order attribute.
4032 Error_Msg_N
4034 Error_Msg_N
4037 -- Here is where we do the processing to adjust component clauses
4038 -- for reversed bit order, when not using reverse SSO.
4042 then
4045 -- Case where we have both an explicit Bit_Order and the same
4046 -- Scalar_Storage_Order: leave record untouched, the back-end
4047 -- will take care of required layout conversions.
4049 else
4055 -- Complete error checking on record representation clause (e.g.
4056 -- overlap of components). This is called after adjusting the
4057 -- record for reverse bit order.
4059 declare
4061 begin
4067 -- Set OK_To_Reorder_Components depending on debug flags
4071 or else
4073 then
4078 -- Check for useless pragma Pack when all components placed. We only
4079 -- do this check for record types, not subtypes, since a subtype may
4080 -- have all its components placed, and it still makes perfectly good
4081 -- sense to pack other subtypes or the parent type. We do not give
4082 -- this warning if Optimize_Alignment is set to Space, since the
4083 -- pragma Pack does have an effect in this case (it always resets
4084 -- the alignment to one).
4088 and then not Unplaced_Component
4090 then
4091 -- Reset packed status. Probably not necessary, but we do it so
4092 -- that there is no chance of the back end doing something strange
4093 -- with this redundant indication of packing.
4097 -- Give warning if redundant constructs warnings on
4100 Error_Msg_N -- CODEFIX
4106 -- If this is the record corresponding to a remote type, freeze the
4107 -- remote type here since that is what we are semantically freezing.
4108 -- This prevents the freeze node for that type in an inner scope.
4115 -- Check for controlled components and unchecked unions.
4120 -- Do not set Has_Controlled_Component on a class-wide
4121 -- equivalent type. See Make_CW_Equivalent_Type.
4124 and then
4126 or else
4129 or else
4131 and then
4133 and then
4134 Has_Controlled_Component
4136 then
4144 -- Scan component declaration for likely misuses of current
4145 -- instance, either in a constraint or a default expression.
4155 -- Enforce the restriction that access attributes with a current
4156 -- instance prefix can only apply to limited types. This comment
4157 -- is floating here, but does not seem to belong here???
4159 -- Set component alignment if not otherwise already set
4163 -- For first subtypes, check if there are any fixed-point fields with
4164 -- component clauses, where we must check the size. This is not done
4165 -- till the freeze point since for fixed-point types, we do not know
4166 -- the size until the type is frozen. Similar processing applies to
4167 -- bit packed arrays.
4175 then
4176 Check_Size
4180 Junk);
4187 -- Generate warning for applying C or C++ convention to a record
4188 -- with discriminants. This is suppressed for the unchecked union
4189 -- case, since the whole point in this case is interface C. We also
4190 -- do not generate this within instantiations, since we will have
4191 -- generated a message on the template.
4196 or else
4199 and then not In_Instance
4202 then
4203 declare
4207 begin
4212 Error_Msg_N
4214 A2);
4215 else
4216 Error_Msg_N
4218 A2);
4221 Error_Msg_NE
4227 -- See if Size is too small as is (and implicit packing might help)
4231 -- No implicit packing if even one component is explicitly placed
4233 and then not Placed_Component
4235 -- Or even one component is aliased
4237 and then not Aliased_Component
4239 -- Must have size clause and all scalar components
4242 and then All_Scalar_Components
4244 -- Do not try implicit packing on records with discriminants, too
4245 -- complicated, especially in the variant record case.
4249 -- We can implicitly pack if the specified size of the record is
4250 -- less than the sum of the object sizes (no point in packing if
4251 -- this is not the case).
4255 -- And the total RM size cannot be greater than the specified size
4256 -- since otherwise packing will not get us where we have to be.
4260 -- Never do implicit packing in CodePeer or SPARK modes since
4261 -- we don't do any packing in these modes, since this generates
4262 -- over-complex code that confuses static analysis, and in
4263 -- general, neither CodePeer not GNATprove care about the
4264 -- internal representation of objects.
4267 then
4268 -- If implicit packing enabled, do it
4273 -- Otherwise flag the size clause
4275 else
4276 declare
4278 begin
4279 Error_Msg_NE -- CODEFIX
4281 Error_Msg_N -- CODEFIX
4288 -- The following checks are only relevant when SPARK_Mode is on as
4289 -- they are not standard Ada legality rules.
4294 -- A discriminated type cannot be effectively volatile
4295 -- (SPARK RM C.6(4)).
4300 -- A tagged type cannot be effectively volatile
4301 -- (SPARK RM C.6(5)).
4307 -- A non-effectively volatile record type cannot contain
4308 -- effectively volatile components (SPARK RM C.6(2)).
4310 else
4315 then
4317 Error_Msg_N
4327 -- Make sure that if we have an iterator aspect, then we have
4328 -- either Constant_Indexing or Variable_Indexing.
4330 declare
4333 begin
4342 or else
4344 then
4346 else
4347 Error_Msg_N
4349 Iterator_Aspect);
4354 -- All done if not a full record definition
4360 -- Finally we need to check the variant part to make sure that
4361 -- all types within choices are properly frozen as part of the
4362 -- freezing of the record type.
4369 begin
4370 -- Find component list
4382 then
4387 -- Case of variant part present
4393 -- Note: we used to call Check_Choices here, but it is too early,
4394 -- since predicated subtypes are frozen here, but their freezing
4395 -- actions are in Analyze_Freeze_Entity, which has not been called
4396 -- yet for entities frozen within this procedure, so we moved that
4397 -- call to the Analyze_Freeze_Entity for the record type.
4401 -- Check that all the primitives of an interface type are abstract
4402 -- or null procedures.
4406 then
4407 declare
4411 begin
4418 -- Avoid reporting the error on inherited primitives
4421 then
4426 Error_Msg_N
4430 else
4431 Error_Msg_N
4443 -------------------------------
4444 -- Has_Boolean_Aspect_Import --
4445 -------------------------------
4452 begin
4458 -- The value of aspect Import is True when the expression is
4459 -- either missing or it is explicitly set to True.
4465 then
4476 ----------------------------
4477 -- Late_Freeze_Subprogram --
4478 ----------------------------
4485 begin
4488 else
4495 ---------------------
4496 -- Restore_Globals --
4497 ---------------------
4500 begin
4504 ------------------------------
4505 -- Wrap_Imported_Subprogram --
4506 ------------------------------
4508 -- The issue here is that our normal approach of checking preconditions
4509 -- and postconditions does not work for imported procedures, since we
4510 -- are not generating code for the body. To get around this we create
4511 -- a wrapper, as shown by the following example:
4513 -- procedure K (A : Integer);
4514 -- pragma Import (C, K);
4516 -- The spec is rewritten by removing the effects of pragma Import, but
4517 -- leaving the convention unchanged, as though the source had said:
4519 -- procedure K (A : Integer);
4520 -- pragma Convention (C, K);
4522 -- and we create a body, added to the entity K freeze actions, which
4523 -- looks like:
4525 -- procedure K (A : Integer) is
4526 -- procedure K (A : Integer);
4527 -- pragma Import (C, K);
4528 -- begin
4529 -- K (A);
4530 -- end K;
4532 -- Now the contract applies in the normal way to the outer procedure,
4533 -- and the inner procedure has no contracts, so there is no problem
4534 -- in just calling it to get the original effect.
4536 -- In the case of a function, we create an appropriate return statement
4537 -- for the subprogram body that calls the inner procedure.
4549 begin
4550 -- Nothing to do if not imported
4555 -- Test enabling conditions for wrapping
4560 and then not GNATprove_Mode
4561 then
4562 -- Here we do the wrap
4564 -- Note on calls to Copy_Separate_Tree. The trees we are copying
4565 -- here are fully analyzed, but we definitely want fully syntactic
4566 -- unanalyzed trees in the body we construct, so that the analysis
4567 -- generates the right visibility, and that is exactly what the
4568 -- calls to Copy_Separate_Tree give us.
4570 -- Acquire copy of Inline pragma, and indicate that it does not
4571 -- come from an aspect, as it applies to an internal entity.
4576 -- Fix up spec to be not imported any more
4583 -- Grab the subprogram declaration and specification
4587 -- Build parameter list that we need
4596 -- Build the call
4599 Stmt :=
4601 Expression =>
4606 else
4607 Stmt :=
4613 -- Now build the body
4615 Bod :=
4617 Specification =>
4621 Specification =>
4623 Iprag),
4624 Handled_Statement_Sequence =>
4629 -- Append the body to freeze result
4634 -- Case of imported subprogram that does not get wrapped
4636 else
4637 -- Set Is_Public. All imported entities need an external symbol
4638 -- created for them since they are always referenced from another
4639 -- object file. Note this used to be set when we set Is_Imported
4640 -- back in Sem_Prag, but now we delay it to this point, since we
4641 -- don't want to set this flag if we wrap an imported subprogram.
4647 -- Start of processing for Freeze_Entity
4649 begin
4650 -- The entity being frozen may be subject to pragma Ghost with policy
4651 -- Ignore. Set the mode now to ensure that any nodes generated during
4652 -- freezing are properly flagged as ignored Ghost.
4656 -- We are going to test for various reasons why this entity need not be
4657 -- frozen here, but in the case of an Itype that's defined within a
4658 -- record, that test actually applies to the record.
4664 then
4668 -- Do not freeze if already frozen since we only need one freeze node
4671 Restore_Globals;
4674 -- It is improper to freeze an external entity within a generic because
4675 -- its freeze node will appear in a non-valid context. The entity will
4676 -- be frozen in the proper scope after the current generic is analyzed.
4677 -- However, aspects must be analyzed because they may be queried later
4678 -- within the generic itself, and the corresponding pragma or attribute
4679 -- definition has not been analyzed yet.
4686 Restore_Globals;
4689 -- AI05-0213: A formal incomplete type does not freeze the actual. In
4690 -- the instance, the same applies to the subtype renaming the actual.
4696 then
4697 Restore_Globals;
4700 -- Formal subprograms are never frozen
4703 Restore_Globals;
4706 -- Generic types are never frozen as they lack delayed semantic checks
4709 Restore_Globals;
4712 -- Do not freeze a global entity within an inner scope created during
4713 -- expansion. A call to subprogram E within some internal procedure
4714 -- (a stream attribute for example) might require freezing E, but the
4715 -- freeze node must appear in the same declarative part as E itself.
4716 -- The two-pass elaboration mechanism in gigi guarantees that E will
4717 -- be frozen before the inner call is elaborated. We exclude constants
4718 -- from this test, because deferred constants may be frozen early, and
4719 -- must be diagnosed (e.g. in the case of a deferred constant being used
4720 -- in a default expression). If the enclosing subprogram comes from
4721 -- source, or is a generic instance, then the freeze point is the one
4722 -- mandated by the language, and we freeze the entity. A subprogram that
4723 -- is a child unit body that acts as a spec does not have a spec that
4724 -- comes from source, but can only come from source.
4729 then
4730 declare
4733 begin
4740 then
4742 else
4743 Restore_Globals;
4752 -- Similarly, an inlined instance body may make reference to global
4753 -- entities, but these references cannot be the proper freezing point
4754 -- for them, and in the absence of inlining freezing will take place in
4755 -- their own scope. Normally instance bodies are analyzed after the
4756 -- enclosing compilation, and everything has been frozen at the proper
4757 -- place, but with front-end inlining an instance body is compiled
4758 -- before the end of the enclosing scope, and as a result out-of-order
4759 -- freezing must be prevented.
4761 elsif Front_End_Inlining
4762 and then In_Instance_Body
4764 then
4765 declare
4768 begin
4773 else
4779 Restore_Globals;
4787 Restore_Globals;
4791 -- Add checks to detect proper initialization of scalars that may appear
4792 -- as subprogram parameters.
4798 -- Deal with delayed aspect specifications. The analysis of the aspect
4799 -- is required to be delayed to the freeze point, thus we analyze the
4800 -- pragma or attribute definition clause in the tree at this point. We
4801 -- also analyze the aspect specification node at the freeze point when
4802 -- the aspect doesn't correspond to pragma/attribute definition clause.
4808 -- Here to freeze the entity
4812 -- Case of entity being frozen is other than a type
4816 -- If entity is exported or imported and does not have an external
4817 -- name, now is the time to provide the appropriate default name.
4818 -- Skip this if the entity is stubbed, since we don't need a name
4819 -- for any stubbed routine. For the case on intrinsics, if no
4820 -- external name is specified, then calls will be handled in
4821 -- Exp_Intr.Expand_Intrinsic_Call, and no name is needed. If an
4822 -- external name is provided, then Expand_Intrinsic_Call leaves
4823 -- calls in place for expansion by GIGI.
4829 then
4830 Set_Encoded_Interface_Name
4833 -- If entity is an atomic object appearing in a declaration and
4834 -- the expression is an aggregate, assign it to a temporary to
4835 -- ensure that the actual assignment is done atomically rather
4836 -- than component-wise (the assignment to the temp may be done
4837 -- component-wise, but that is harmless).
4844 then
4848 -- Subprogram case
4852 -- Check for needing to wrap imported subprogram
4856 -- Freeze all parameter types and the return type (RM 13.14(14)).
4857 -- However skip this for internal subprograms. This is also where
4858 -- any extra formal parameters are created since we now know
4859 -- whether the subprogram will use a foreign convention.
4861 -- In Ada 2012, freezing a subprogram does not always freeze
4862 -- the corresponding profile (see AI05-019). An attribute
4863 -- reference is not a freezing point of the profile.
4864 -- Other constructs that should not freeze ???
4866 -- This processing doesn't apply to internal entities (see below)
4870 Restore_Globals;
4875 -- Must freeze its parent first if it is a derived subprogram
4881 -- We don't freeze internal subprograms, because we don't normally
4882 -- want addition of extra formals or mechanism setting to happen
4883 -- for those. However we do pass through predefined dispatching
4884 -- cases, since extra formals may be needed in some cases, such as
4885 -- for the stream 'Input function (build-in-place formals).
4889 then
4895 Restore_Globals;
4899 -- If warning on suspicious contracts then check for the case of
4900 -- a postcondition other than False for a No_Return subprogram.
4903 and then Warn_On_Suspicious_Contract
4905 then
4906 declare
4910 begin
4913 Name_Postcondition,
4914 Name_Refined_Post)
4915 then
4916 Exp :=
4917 Expression
4922 then
4923 Error_Msg_NE
4934 -- Here for other than a subprogram or type
4936 else
4937 -- If entity has a type, and it is not a generic unit, then
4938 -- freeze it first (RM 13.14(10)).
4942 then
4945 -- For an object of an anonymous array type, aspects on the
4946 -- object declaration apply to the type itself. This is the
4947 -- case for Atomic_Components, Volatile_Components, and
4948 -- Independent_Components. In these cases analysis of the
4949 -- generated pragma will mark the anonymous types accordingly,
4950 -- and the object itself does not require a freeze node.
4956 then
4963 -- Special processing for objects created by object declaration
4969 -- Check that a constant which has a pragma Volatile[_Components]
4970 -- or Atomic[_Components] also has a pragma Import (RM C.6(13)).
4972 -- Note: Atomic[_Components] also sets Volatile[_Components]
4978 then
4979 -- Make sure we actually have a pragma, and have not merely
4980 -- inherited the indication from elsewhere (e.g. an address
4981 -- clause, which is not good enough in RM terms).
4984 or else
4986 then
4987 Error_Msg_N
4992 or else
4994 then
4995 Error_Msg_N
5001 -- Static objects require special handling
5005 then
5009 -- Remaining step is to layout objects
5013 then
5017 -- For an object that does not have delayed freezing, and whose
5018 -- initialization actions have been captured in a compound
5019 -- statement, move them back now directly within the enclosing
5020 -- statement sequence.
5024 then
5029 -- Case of a type or subtype being frozen
5031 else
5032 -- We used to check here that a full type must have preelaborable
5033 -- initialization if it completes a private type specified with
5034 -- pragma Preelaborable_Initialization, but that missed cases where
5035 -- the types occur within a generic package, since the freezing
5036 -- that occurs within a containing scope generally skips traversal
5037 -- of a generic unit's declarations (those will be frozen within
5038 -- instances). This check was moved to Analyze_Package_Specification.
5040 -- The type may be defined in a generic unit. This can occur when
5041 -- freezing a generic function that returns the type (which is
5042 -- defined in a parent unit). It is clearly meaningless to freeze
5043 -- this type. However, if it is a subtype, its size may be determi-
5044 -- nable and used in subsequent checks, so might as well try to
5045 -- compute it.
5047 -- In Ada 2012, Freeze_Entities is also used in the front end to
5048 -- trigger the analysis of aspect expressions, so in this case we
5049 -- want to continue the freezing process.
5053 and then
5056 then
5058 Restore_Globals;
5062 -- Check for error of Type_Invariant'Class applied to an untagged
5063 -- type (check delayed to freeze time when full type is available).
5065 declare
5067 begin
5071 then
5072 Error_Msg_NE
5075 Error_Msg_N
5080 -- A Ghost type cannot be effectively volatile (SPARK RM 6.9(8))
5084 then
5088 -- Deal with special cases of freezing for subtype
5092 -- Before we do anything else, a specialized test for the case of
5093 -- a size given for an array where the array needs to be packed,
5094 -- but was not so the size cannot be honored. This is the case
5095 -- where implicit packing may apply. The reason we do this so
5096 -- early is that if we have implicit packing, the layout of the
5097 -- base type is affected, so we must do this before we freeze
5098 -- the base type.
5100 -- We could do this processing only if implicit packing is enabled
5101 -- since in all other cases, the error would be caught by the back
5102 -- end. However, we choose to do the check even if we do not have
5103 -- implicit packing enabled, since this allows us to give a more
5104 -- useful error message (advising use of pragmas Implicit_Packing
5105 -- or Pack).
5108 declare
5119 -- Number of elements in array
5121 begin
5122 -- Check enabling conditions. These are straightforward
5123 -- except for the test for a limited composite type. This
5124 -- eliminates the rare case of a array of limited components
5125 -- where there are issues of whether or not we can go ahead
5126 -- and pack the array (since we can't freely pack and unpack
5127 -- arrays if they are limited).
5129 -- Note that we check the root type explicitly because the
5130 -- whole point is we are doing this test before we have had
5131 -- a chance to freeze the base type (and it is that freeze
5132 -- action that causes stuff to be inherited).
5145 then
5146 -- Compute number of elements in array
5154 and then
5156 then
5160 Num_Elmts :=
5161 Num_Elmts *
5167 -- What we are looking for here is the situation where
5168 -- the RM_Size given would be exactly right if there was
5169 -- a pragma Pack (resulting in the component size being
5170 -- the same as the RM_Size). Furthermore, the component
5171 -- type size must be an odd size (not a multiple of
5172 -- storage unit). If the component RM size is an exact
5173 -- number of storage units that is a power of two, the
5174 -- array is not packed and has a standard representation.
5178 then
5179 -- For implicit packing mode, just set the component
5180 -- size silently.
5188 -- Otherwise give an error message
5190 else
5191 Error_Msg_NE
5193 Error_Msg_N -- CODEFIX
5199 and then Implicit_Packing
5200 and then
5202 or else
5204 or else
5206 then
5207 -- Not a packed array, but indicate the desired
5208 -- component size, for the back-end.
5218 -- If ancestor subtype present, freeze that first. Note that this
5219 -- will also get the base type frozen. Need RM reference ???
5226 -- No ancestor subtype present
5228 else
5229 -- See if we have a nearest ancestor that has a predicate.
5230 -- That catches the case of derived type with a predicate.
5231 -- Need RM reference here ???
5239 -- Freeze base type before freezing the entity (RM 13.14(15))
5246 -- A subtype inherits all the type-related representation aspects
5247 -- from its parents (RM 13.1(8)).
5251 -- For a derived type, freeze its parent type first (RM 13.14(15))
5257 -- A derived type inherits each type-related representation aspect
5258 -- of its parent type that was directly specified before the
5259 -- declaration of the derived type (RM 13.1(15)).
5264 -- Check for incompatible size and alignment for record type
5266 if Warn_On_Size_Alignment
5270 -- If explicit Object_Size clause given assume that the programmer
5271 -- knows what he is doing, and expects the compiler behavior.
5275 -- Check for size not a multiple of alignment
5278 then
5279 declare
5285 begin
5288 -- Give a warning
5292 Error_Msg_NE
5299 else
5301 Error_Msg_NE
5315 -- Array type
5320 -- For a class-wide type, the corresponding specific type is
5321 -- frozen as well (RM 13.14(15))
5326 -- If the base type of the class-wide type is still incomplete,
5327 -- the class-wide remains unfrozen as well. This is legal when
5328 -- E is the formal of a primitive operation of some other type
5329 -- which is being frozen.
5333 Restore_Globals;
5337 -- The equivalent type associated with a class-wide subtype needs
5338 -- to be frozen to ensure that its layout is done.
5342 then
5346 -- Generate an itype reference for a library-level class-wide type
5347 -- at the freeze point. Otherwise the first explicit reference to
5348 -- the type may appear in an inner scope which will be rejected by
5349 -- the back-end.
5353 then
5354 declare
5357 begin
5360 -- From a gigi point of view, a class-wide subtype derives
5361 -- from its record equivalent type. As a result, the itype
5362 -- reference must appear after the freeze node of the
5363 -- equivalent type or gigi will reject the reference.
5367 then
5369 else
5375 -- For a record type or record subtype, freeze all component types
5376 -- (RM 13.14(15)). We test for E_Record_(sub)Type here, rather than
5377 -- using Is_Record_Type, because we don't want to attempt the freeze
5378 -- for the case of a private type with record extension (we will do
5379 -- that later when the full type is frozen).
5384 then
5387 -- For a concurrent type, freeze corresponding record type. This does
5388 -- not correspond to any specific rule in the RM, but the record type
5389 -- is essentially part of the concurrent type. Also freeze all local
5390 -- entities. This includes record types created for entry parameter
5391 -- blocks and whatever local entities may appear in the private part.
5405 -- The guard on the presence of the Etype seems to be needed
5406 -- for some CodePeer (-gnatcC) cases, but not clear why???
5411 then
5422 -- Private types are required to point to the same freeze node as
5423 -- their corresponding full views. The freeze node itself has to
5424 -- point to the partial view of the entity (because from the partial
5425 -- view, we can retrieve the full view, but not the reverse).
5426 -- However, in order to freeze correctly, we need to freeze the full
5427 -- view. If we are freezing at the end of a scope (or within the
5428 -- scope) of the private type, the partial and full views will have
5429 -- been swapped, the full view appears first in the entity chain and
5430 -- the swapping mechanism ensures that the pointers are properly set
5431 -- (on scope exit).
5433 -- If we encounter the partial view before the full view (e.g. when
5434 -- freezing from another scope), we freeze the full view, and then
5435 -- set the pointers appropriately since we cannot rely on swapping to
5436 -- fix things up (subtypes in an outer scope might not get swapped).
5438 -- If the full view is itself private, the above requirements apply
5439 -- to the underlying full view instead of the full view. But there is
5440 -- no swapping mechanism for the underlying full view so we need to
5441 -- set the pointers appropriately in both cases.
5445 then
5446 -- The construction of the dispatch table associated with library
5447 -- level tagged types forces freezing of all the primitives of the
5448 -- type, which may cause premature freezing of the partial view.
5449 -- For example:
5451 -- package Pkg is
5452 -- type T is tagged private;
5453 -- type DT is new T with private;
5454 -- procedure Prim (X : in out T; Y : in out DT'Class);
5455 -- private
5456 -- type T is tagged null record;
5457 -- Obj : T;
5458 -- type DT is new T with null record;
5459 -- end;
5461 -- In this case the type will be frozen later by the usual
5462 -- mechanism: an object declaration, an instantiation, or the
5463 -- end of a declarative part.
5467 then
5469 Restore_Globals;
5472 -- Case of full view present
5476 -- If full view has already been frozen, then no further
5477 -- processing is required
5483 -- Otherwise freeze full view and patch the pointers so that
5484 -- the freeze node will elaborate both views in the back end.
5485 -- However, if full view is itself private, freeze underlying
5486 -- full view instead and patch the pointers so that the freeze
5487 -- node will elaborate the three views in the back end.
5489 else
5490 declare
5493 begin
5496 then
5504 then
5511 else
5524 else
5525 -- {Incomplete,Private}_Subtypes with Full_Views
5526 -- constrained by discriminants.
5537 -- AI-117 requires that the convention of a partial view be the
5538 -- same as the convention of the full view. Note that this is a
5539 -- recognized breach of privacy, but it's essential for logical
5540 -- consistency of representation, and the lack of a rule in
5541 -- RM95 was an oversight.
5548 -- Size information is copied from the full view to the
5549 -- incomplete or private view for consistency.
5551 -- We skip this is the full view is not a type. This is very
5552 -- strange of course, and can only happen as a result of
5553 -- certain illegalities, such as a premature attempt to derive
5554 -- from an incomplete type.
5561 Restore_Globals;
5564 -- Case of underlying full view present
5568 then
5573 -- Patch the pointers so that the freeze node will elaborate
5574 -- both views in the back end.
5583 else
5591 Restore_Globals;
5594 -- Case of no full view present. If entity is derived or subtype,
5595 -- it is safe to freeze, correctness depends on the frozen status
5596 -- of parent. Otherwise it is either premature usage, or a Taft
5597 -- amendment type, so diagnosis is at the point of use and the
5598 -- type might be frozen later.
5603 else
5605 Restore_Globals;
5609 -- For access subprogram, freeze types of all formals, the return
5610 -- type was already frozen, since it is the Etype of the function.
5611 -- Formal types can be tagged Taft amendment types, but otherwise
5612 -- they cannot be incomplete.
5620 then
5624 -- AI05-151: Incomplete types are allowed in access to
5625 -- subprogram specifications.
5628 Error_Msg_NE
5639 -- For access to a protected subprogram, freeze the equivalent type
5640 -- (however this is not set if we are not generating code or if this
5641 -- is an anonymous type used just for resolution).
5649 -- Generic types are never seen by the back-end, and are also not
5650 -- processed by the expander (since the expander is turned off for
5651 -- generic processing), so we never need freeze nodes for them.
5654 Restore_Globals;
5658 -- Some special processing for non-generic types to complete
5659 -- representation details not known till the freeze point.
5664 -- Some error checks required for ordinary fixed-point type. Defer
5665 -- these till the freeze-point since we need the small and range
5666 -- values. We only do these checks for base types
5671 Error_Msg_N
5676 Error_Msg_N
5682 Error_Msg_N
5688 Error_Msg_N
5700 and then Warn_On_Suspicious_Modulus_Value
5701 then
5705 -- The pool applies to named and anonymous access types, but not
5706 -- to subprogram and to internal types generated for 'Access
5707 -- references.
5712 then
5713 -- If a pragma Default_Storage_Pool applies, and this type has no
5714 -- Storage_Pool or Storage_Size clause (which must have occurred
5715 -- before the freezing point), then use the default. This applies
5716 -- only to base types.
5718 -- None of this applies to access to subprograms, for which there
5719 -- are clearly no pools.
5725 then
5726 -- Case of pragma Default_Storage_Pool (null)
5731 -- Case of pragma Default_Storage_Pool (storage_pool_NAME)
5733 else
5738 -- Check restriction for standard storage pool
5744 -- Deal with error message for pure access type. This is not an
5745 -- error in Ada 2005 if there is no pool (see AI-366).
5751 then
5755 Error_Msg_N
5759 Error_Msg_N
5762 else
5763 Error_Msg_N
5770 -- Case of composite types
5774 -- AI-117 requires that all new primitives of a tagged type must
5775 -- inherit the convention of the full view of the type. Inherited
5776 -- and overriding operations are defined to inherit the convention
5777 -- of their parent or overridden subprogram (also specified in
5778 -- AI-117), which will have occurred earlier (in Derive_Subprogram
5779 -- and New_Overloaded_Entity). Here we set the convention of
5780 -- primitives that are still convention Ada, which will ensure
5781 -- that any new primitives inherit the type's convention. Class-
5782 -- wide types can have a foreign convention inherited from their
5783 -- specific type, but are excluded from this since they don't have
5784 -- any associated primitives.
5789 then
5790 declare
5794 begin
5806 -- If the type is a simple storage pool type, then this is where
5807 -- we attempt to locate and validate its Allocate, Deallocate, and
5808 -- Storage_Size operations (the first is required, and the latter
5809 -- two are optional). We also verify that the full type for a
5810 -- private type is allowed to be a simple storage pool type.
5814 then
5815 -- If the type is marked Has_Private_Declaration, then this is
5816 -- a full type for a private type that was specified with the
5817 -- pragma Simple_Storage_Pool_Type, and here we ensure that the
5818 -- pragma is allowed for the full type (for example, it can't
5819 -- be an array type, or a nonlimited record type).
5824 then
5826 Error_Msg_N
5837 procedure Validate_Simple_Pool_Op_Formal
5844 -- Validate one formal Pool_Op_Formal of the candidate pool
5845 -- operation Pool_Op. The formal must be of Expected_Type
5846 -- and have mode Expected_Mode. OK_Formal will be set to
5847 -- False if the formal doesn't match. If OK_Formal is False
5848 -- on entry, then the formal will effectively be ignored
5849 -- (because validation of the pool op has already failed).
5850 -- Upon return, Pool_Op_Formal will be updated to the next
5851 -- formal, if any.
5853 procedure Validate_Simple_Pool_Operation
5855 -- Search for and validate a simple pool operation with the
5856 -- name Op_Name. If the name is Allocate, then there must be
5857 -- exactly one such primitive operation for the simple pool
5858 -- type. If the name is Deallocate or Storage_Size, then
5859 -- there can be at most one such primitive operation. The
5860 -- profile of the located primitive must conform to what
5861 -- is expected for each operation.
5863 ------------------------------------
5864 -- Validate_Simple_Pool_Op_Formal --
5865 ------------------------------------
5867 procedure Validate_Simple_Pool_Op_Formal
5874 is
5875 begin
5876 -- If OK_Formal is False on entry, then simply ignore
5877 -- the formal, because an earlier formal has already
5878 -- been flagged.
5883 -- If no formal is passed in, then issue an error for a
5884 -- missing formal.
5887 Error_Msg_NE
5897 -- If the pool type was expected for this formal, then
5898 -- this will not be considered a candidate operation
5899 -- for the simple pool, so we unset OK_Formal so that
5900 -- the op and any later formals will be ignored.
5907 else
5908 Error_Msg_NE
5915 -- Issue error if formal's mode is not the expected one
5918 Error_Msg_N
5920 Pool_Op_Formal);
5923 -- Advance to the next formal
5928 ------------------------------------
5929 -- Validate_Simple_Pool_Operation --
5930 ------------------------------------
5932 procedure Validate_Simple_Pool_Operation
5934 is
5940 begin
5941 pragma Assert
5943 Name_Deallocate,
5944 Name_Storage_Size));
5948 -- For each homonym declared immediately in the scope
5949 -- of the simple storage pool type, determine whether
5950 -- the homonym is an operation of the pool type, and,
5951 -- if so, check that its profile is as expected for
5952 -- a simple pool operation of that name.
5958 then
5963 -- The first parameter must be of the pool type
5964 -- in order for the operation to qualify.
5967 Validate_Simple_Pool_Op_Formal
5970 else
5971 Validate_Simple_Pool_Op_Formal
5976 -- If another operation with this name has already
5977 -- been located for the type, then flag an error,
5978 -- since we only allow the type to have a single
5979 -- such primitive.
5982 Error_Msg_NE
5987 -- In the case of Allocate and Deallocate, a formal
5988 -- of type System.Address is required.
5991 Validate_Simple_Pool_Op_Formal
5996 Validate_Simple_Pool_Op_Formal
6001 -- In the case of Allocate and Deallocate, formals
6002 -- of type Storage_Count are required as the third
6003 -- and fourth parameters.
6006 Validate_Simple_Pool_Op_Formal
6009 Validate_Simple_Pool_Op_Formal
6014 -- If no mismatched formals have been found (Is_OK)
6015 -- and no excess formals are present, then this
6016 -- operation has been validated, so record it.
6026 -- There must be a valid Allocate operation for the type,
6027 -- so issue an error if none was found.
6031 then
6037 -- Simple pool operations can't be abstract
6040 Error_Msg_N
6045 -- The Storage_Size operation must be a function with
6046 -- Storage_Count as its result type.
6050 Error_Msg_N
6054 Error_Msg_NE
6059 -- Allocate and Deallocate must be procedures
6062 Error_Msg_N
6068 -- Start of processing for Validate_Simple_Pool_Ops
6070 begin
6078 -- Now that all types from which E may depend are frozen, see if the
6079 -- size is known at compile time, if it must be unsigned, or if
6080 -- strict alignment is required
6089 -- Do not allow a size clause for a type which does not have a size
6090 -- that is known at compile time
6094 then
6095 -- Suppress this message if errors posted on E, even if we are
6096 -- in all errors mode, since this is often a junk message
6099 Error_Msg_N
6105 -- Now we set/verify the representation information, in particular
6106 -- the size and alignment values. This processing is not required for
6107 -- generic types, since generic types do not play any part in code
6108 -- generation, and so the size and alignment values for such types
6109 -- are irrelevant. Ditto for types declared within a generic unit,
6110 -- which may have components that depend on generic parameters, and
6111 -- that will be recreated in an instance.
6116 -- Otherwise we call the layout procedure
6118 else
6122 -- If this is an access to subprogram whose designated type is itself
6123 -- a subprogram type, the return type of this anonymous subprogram
6124 -- type must be decorated as well.
6128 then
6132 -- If the type has a Defaut_Value/Default_Component_Value aspect,
6133 -- this is where we analye the expression (after the type is frozen,
6134 -- since in the case of Default_Value, we are analyzing with the
6135 -- type itself, and we treat Default_Component_Value similarly for
6136 -- the sake of uniformity).
6139 declare
6144 begin
6149 else
6160 Flag_Non_Static_Expr
6167 -- End of freeze processing for type entities
6170 -- Here is where we logically freeze the current entity. If it has a
6171 -- freeze node, then this is the point at which the freeze node is
6172 -- linked into the result list.
6176 -- If a freeze node is already allocated, use it, otherwise allocate
6177 -- a new one. The preallocation happens in the case of anonymous base
6178 -- types, where we preallocate so that we can set First_Subtype_Link.
6179 -- Note that we reset the Sloc to the current freeze location.
6185 else
6196 -- A final pass over record types with discriminants. If the type
6197 -- has an incomplete declaration, there may be constrained access
6198 -- subtypes declared elsewhere, which do not depend on the discrimi-
6199 -- nants of the type, and which are used as component types (i.e.
6200 -- the full view is a recursive type). The designated types of these
6201 -- subtypes can only be elaborated after the type itself, and they
6202 -- need an itype reference.
6206 then
6207 declare
6212 begin
6222 then
6234 -- When a type is frozen, the first subtype of the type is frozen as
6235 -- well (RM 13.14(15)). This has to be done after freezing the type,
6236 -- since obviously the first subtype depends on its own base type.
6241 -- If we just froze a tagged non-class wide record, then freeze the
6242 -- corresponding class-wide type. This must be done after the tagged
6243 -- type itself is frozen, because the class-wide type refers to the
6244 -- tagged type which generates the class.
6249 then
6256 -- Special handling for subprograms
6260 -- If subprogram has address clause then reset Is_Public flag, since
6261 -- we do not want the backend to generate external references.
6265 then
6270 Restore_Globals;
6274 -----------------------------
6275 -- Freeze_Enumeration_Type --
6276 -----------------------------
6279 begin
6280 -- By default, if no size clause is present, an enumeration type with
6281 -- Convention C is assumed to interface to a C enum, and has integer
6282 -- size. This applies to types. For subtypes, verify that its base
6283 -- type has no size clause either. Treat other foreign conventions
6284 -- in the same way, and also make sure alignment is set right.
6291 -- Don't do this if Short_Enums on target
6293 and then not Target_Short_Enums
6294 then
6298 -- Normal Ada case or size clause present or not Long_C_Enums on target
6300 else
6301 -- If the enumeration type interfaces to C, and it has a size clause
6302 -- that specifies less than int size, it warrants a warning. The
6303 -- user may intend the C type to be an enum or a char, so this is
6304 -- not by itself an error that the Ada compiler can detect, but it
6305 -- it is a worth a heads-up. For Boolean and Character types we
6306 -- assume that the programmer has the proper C type in mind.
6314 -- Don't do this if Short_Enums on target
6316 and then not Target_Short_Enums
6317 then
6318 Error_Msg_N
6326 -----------------------
6327 -- Freeze_Expression --
6328 -----------------------
6339 -- This flag is set true if the entity must be frozen outside the
6340 -- current subprogram. This happens in the case of expander generated
6341 -- subprograms (_Init_Proc, _Input, _Output, _Read, _Write) which do
6342 -- not freeze all entities like other bodies, but which nevertheless
6343 -- may reference entities that have to be frozen before the body and
6344 -- obviously cannot be frozen inside the body.
6347 -- If the expression is an array aggregate, the type of the component
6348 -- expressions is also frozen. If the component type is an access type
6349 -- and the expressions include allocators, the designed type is frozen
6350 -- as well.
6353 -- Given an N_Handled_Sequence_Of_Statements node N, determines whether
6354 -- it is the handled statement sequence of an expander-generated
6355 -- subprogram (init proc, stream subprogram, or renaming as body).
6356 -- If so, this is not a freezing context.
6358 -----------------------------------------
6359 -- Find_Aggregate_Component_Desig_Type --
6360 -----------------------------------------
6366 begin
6392 ----------------------
6393 -- In_Expanded_Body --
6394 ----------------------
6400 begin
6403 else
6410 else
6413 -- The following are expander-created bodies, or bodies that
6414 -- are not freeze points.
6423 N_Subprogram_Renaming_Declaration,
6424 N_Expression_Function))
6425 then
6427 else
6433 -- Start of processing for Freeze_Expression
6435 begin
6436 -- Immediate return if freezing is inhibited. This flag is set by the
6437 -- analyzer to stop freezing on generated expressions that would cause
6438 -- freezing if they were in the source program, but which are not
6439 -- supposed to freeze, since they are created.
6445 -- If expression is non-static, then it does not freeze in a default
6446 -- expression, see section "Handling of Default Expressions" in the
6447 -- spec of package Sem for further details. Note that we have to make
6448 -- sure that we actually have a real expression (if we have a subtype
6449 -- indication, we can't test Is_OK_Static_Expression). However, we
6450 -- exclude the case of the prefix of an attribute of a static scalar
6451 -- subtype from this early return, because static subtype attributes
6452 -- should always cause freezing, even in default expressions, but
6453 -- the attribute may not have been marked as static yet (because in
6454 -- Resolve_Attribute, the call to Eval_Attribute follows the call of
6455 -- Freeze_Expression on the prefix).
6457 if In_Spec_Exp
6464 then
6468 -- Freeze type of expression if not frozen already
6476 -- Base type may be an derived numeric type that is frozen at
6477 -- the point of declaration, but first_subtype is still unfrozen.
6484 -- For entity name, freeze entity if not frozen already. A special
6485 -- exception occurs for an identifier that did not come from source.
6486 -- We don't let such identifiers freeze a non-internal entity, i.e.
6487 -- an entity that did come from source, since such an identifier was
6488 -- generated by the expander, and cannot have any semantic effect on
6489 -- the freezing semantics. For example, this stops the parameter of
6490 -- an initialization procedure from freezing the variable.
6497 then
6504 else
6508 -- For an allocator freeze designated type if not frozen already
6510 -- For an aggregate whose component type is an access type, freeze the
6511 -- designated type now, so that its freeze does not appear within the
6512 -- loop that might be created in the expansion of the aggregate. If the
6513 -- designated type is a private type without full view, the expression
6514 -- cannot contain an allocator, so the type is not frozen.
6516 -- For a function, we freeze the entity when the subprogram declaration
6517 -- is frozen, but a function call may appear in an initialization proc.
6518 -- before the declaration is frozen. We need to generate the extra
6519 -- formals, if any, to ensure that the expansion of the call includes
6520 -- the proper actuals. This only applies to Ada subprograms, not to
6521 -- imported ones.
6532 then
6534 -- Check whether aggregate includes allocators.
6539 when N_Selected_Component |
6540 N_Indexed_Component |
6541 N_Slice =>
6552 then
6563 then
6567 -- All done if nothing needs freezing
6572 then
6576 -- Examine the enclosing context by climbing the parent chain. The
6577 -- traversal serves two purposes - to detect scenarios where freezeing
6578 -- is not needed and to find the proper insertion point for the freeze
6579 -- nodes. Although somewhat similar to Insert_Actions, this traversal
6580 -- is freezing semantics-sensitive. Inserting freeze nodes blindly in
6581 -- the tree may result in types being frozen too early.
6584 loop
6587 -- If we don't have a parent, then we are not in a well-formed tree.
6588 -- This is an unusual case, but there are some legitimate situations
6589 -- in which this occurs, notably when the expressions in the range of
6590 -- a type declaration are resolved. We simply ignore the freeze
6591 -- request in this case. Is this right ???
6597 -- See if we have got to an appropriate point in the tree
6601 -- A special test for the exception of (RM 13.14(8)) for the case
6602 -- of per-object expressions (RM 3.8(18)) occurring in component
6603 -- definition or a discrete subtype definition. Note that we test
6604 -- for a component declaration which includes both cases we are
6605 -- interested in, and furthermore the tree does not have explicit
6606 -- nodes for either of these two constructs.
6610 -- The case we want to test for here is an identifier that is
6611 -- a per-object expression, this is either a discriminant that
6612 -- appears in a context other than the component declaration
6613 -- or it is a reference to the type of the enclosing construct.
6615 -- For either of these cases, we skip the freezing
6617 if not In_Spec_Expression
6620 then
6621 -- We recognize the discriminant case by just looking for
6622 -- a reference to a discriminant. It can only be one for
6623 -- the enclosing construct. Skip freezing in this case.
6628 -- For the case of a reference to the enclosing record,
6629 -- (or task or protected type), we look for a type that
6630 -- matches the current scope.
6637 -- If we have an enumeration literal that appears as the choice in
6638 -- the aggregate of an enumeration representation clause, then
6639 -- freezing does not occur (RM 13.14(10)).
6643 -- The case we are looking for is an enumeration literal
6647 then
6648 -- If enumeration literal appears directly as the choice,
6649 -- do not freeze (this is the normal non-overloaded case)
6653 then
6656 -- If enumeration literal appears as the name of function
6657 -- which is the choice, then also do not freeze. This
6658 -- happens in the overloaded literal case, where the
6659 -- enumeration literal is temporarily changed to a function
6660 -- call for overloading analysis purposes.
6663 and then
6665 and then
6667 then
6672 -- Normally if the parent is a handled sequence of statements,
6673 -- then the current node must be a statement, and that is an
6674 -- appropriate place to insert a freeze node.
6678 -- An exception occurs when the sequence of statements is for
6679 -- an expander generated body that did not do the usual freeze
6680 -- all operation. In this case we usually want to freeze
6681 -- outside this body, not inside it, and we skip past the
6682 -- subprogram body that we are inside.
6685 declare
6689 begin
6690 -- Freeze the entity only when it is declared inside the
6691 -- body of the expander generated procedure. This case
6692 -- is recognized by the scope of the entity or its type,
6693 -- which is either the spec for some enclosing body, or
6694 -- (in the case of init_procs, for which there are no
6695 -- separate specs) the current scope.
6701 or else
6703 then
6709 then
6714 -- An expression function may act as a completion of
6715 -- a function declaration. As such, it can reference
6716 -- entities declared between the two views:
6718 -- Hidden []; -- 1
6719 -- function F return ...;
6720 -- private
6721 -- function Hidden return ...;
6722 -- function F return ... is (Hidden); -- 2
6724 -- Refering to the example above, freezing the expression
6725 -- of F (2) would place Hidden's freeze node (1) in the
6726 -- wrong place. Avoid explicit freezing and let the usual
6727 -- scenarios do the job - for example, reaching the end
6728 -- of the private declarations, or a call to F.
6731 N_Expression_Function
6732 then
6735 -- Freeze outside the body
6737 else
6743 -- Here if normal case where we are in handled statement
6744 -- sequence and want to do the insertion right there.
6746 else
6750 -- If parent is a body or a spec or a block, then the current node
6751 -- is a statement or declaration and we can insert the freeze node
6752 -- before it.
6754 when N_Block_Statement |
6755 N_Entry_Body |
6756 N_Package_Body |
6757 N_Package_Specification |
6758 N_Protected_Body |
6759 N_Subprogram_Body |
6762 -- The expander is allowed to define types in any statements list,
6763 -- so any of the following parent nodes also mark a freezing point
6764 -- if the actual node is in a list of statements or declarations.
6766 when N_Abortable_Part |
6767 N_Accept_Alternative |
6768 N_And_Then |
6769 N_Case_Statement_Alternative |
6770 N_Compilation_Unit_Aux |
6771 N_Conditional_Entry_Call |
6772 N_Delay_Alternative |
6773 N_Elsif_Part |
6774 N_Entry_Call_Alternative |
6775 N_Exception_Handler |
6776 N_Extended_Return_Statement |
6777 N_Freeze_Entity |
6778 N_If_Statement |
6779 N_Or_Else |
6780 N_Selective_Accept |
6781 N_Triggering_Alternative =>
6785 -- Freeze nodes produced by an expression coming from the Actions
6786 -- list of a N_Expression_With_Actions node must remain within the
6787 -- Actions list. Inserting the freeze nodes further up the tree
6788 -- may lead to use before declaration issues in the case of array
6789 -- types.
6794 then
6798 -- Note: N_Loop_Statement is a special case. A type that appears
6799 -- in the source can never be frozen in a loop (this occurs only
6800 -- because of a loop expanded by the expander), so we keep on
6801 -- going. Otherwise we terminate the search. Same is true of any
6802 -- entity which comes from source. (if they have predefined type,
6803 -- that type does not appear to come from source, but the entity
6804 -- should not be frozen here).
6810 -- For all other cases, keep looking at parents
6816 -- We fall through the case if we did not yet find the proper
6817 -- place in the free for inserting the freeze node, so climb.
6822 -- If the expression appears in a record or an initialization procedure,
6823 -- the freeze nodes are collected and attached to the current scope, to
6824 -- be inserted and analyzed on exit from the scope, to insure that
6825 -- generated entities appear in the correct scope. If the expression is
6826 -- a default for a discriminant specification, the scope is still void.
6827 -- The expression can also appear in the discriminant part of a private
6828 -- or concurrent type.
6830 -- If the expression appears in a constrained subcomponent of an
6831 -- enclosing record declaration, the freeze nodes must be attached to
6832 -- the outer record type so they can eventually be placed in the
6833 -- enclosing declaration list.
6835 -- The other case requiring this special handling is if we are in a
6836 -- default expression, since in that case we are about to freeze a
6837 -- static type, and the freeze scope needs to be the outer scope, not
6838 -- the scope of the subprogram with the default parameter.
6840 -- For default expressions and other spec expressions in generic units,
6841 -- the Move_Freeze_Nodes mechanism (see sem_ch12.adb) takes care of
6842 -- placing them at the proper place, after the generic unit.
6845 or else Freeze_Outside
6850 then
6851 declare
6856 begin
6869 -- The current scope may be that of a constrained component of
6870 -- an enclosing record declaration, or of a loop of an enclosing
6871 -- quantified expression, which is above the current scope in the
6872 -- scope stack. Indeed in the context of a quantified expression,
6873 -- a scope is created and pushed above the current scope in order
6874 -- to emulate the loop-like behavior of the quantified expression.
6875 -- If the expression is within a top-level pragma, as for a pre-
6876 -- condition on a library-level subprogram, nothing to do.
6881 N_Quantified_Expression)
6882 then
6889 Freeze_Nodes;
6890 else
6900 -- Now we have the right place to do the freezing. First, a special
6901 -- adjustment, if we are in spec-expression analysis mode, these freeze
6902 -- actions must not be thrown away (normally all inserted actions are
6903 -- thrown away in this mode. However, the freeze actions are from static
6904 -- expressions and one of the important reasons we are doing this
6905 -- special analysis is to get these freeze actions. Therefore we turn
6906 -- off the In_Spec_Expression mode to propagate these freeze actions.
6907 -- This also means they get properly analyzed and expanded.
6911 -- Freeze the designated type of an allocator (RM 13.14(13))
6917 -- Freeze type of expression (RM 13.14(10)). Note that we took care of
6918 -- the enumeration representation clause exception in the loop above.
6924 -- Freeze name if one is present (RM 13.14(11))
6930 -- Restore In_Spec_Expression flag
6935 -----------------------------
6936 -- Freeze_Fixed_Point_Type --
6937 -----------------------------
6939 -- Certain fixed-point types and subtypes, including implicit base types
6940 -- and declared first subtypes, have not yet set up a range. This is
6941 -- because the range cannot be set until the Small and Size values are
6942 -- known, and these are not known till the type is frozen.
6944 -- To signal this case, Scalar_Range contains an unanalyzed syntactic range
6945 -- whose bounds are unanalyzed real literals. This routine will recognize
6946 -- this case, and transform this range node into a properly typed range
6947 -- with properly analyzed and resolved values.
6964 -- Save original bounds (for shaving tests)
6967 -- Actual size chosen
6970 -- Returns size of type with given bounds. Also leaves these
6971 -- bounds set as the current bounds of the Typ.
6973 -----------
6974 -- Fsize --
6975 -----------
6978 begin
6984 -- Start of processing for Freeze_Fixed_Point_Type
6986 begin
6987 -- If Esize of a subtype has not previously been set, set it now
6994 else
6999 -- Immediate return if the range is already analyzed. This means that
7000 -- the range is already set, and does not need to be computed by this
7001 -- routine.
7007 -- Immediate return if either of the bounds raises Constraint_Error
7011 then
7021 -- Ordinary fixed-point case
7025 -- For the ordinary fixed-point case, we are allowed to fudge the
7026 -- end-points up or down by small. Generally we prefer to fudge up,
7027 -- i.e. widen the bounds for non-model numbers so that the end points
7028 -- are included. However there are cases in which this cannot be
7029 -- done, and indeed cases in which we may need to narrow the bounds.
7030 -- The following circuit makes the decision.
7032 -- Note: our terminology here is that Incl_EP means that the bounds
7033 -- are widened by Small if necessary to include the end points, and
7034 -- Excl_EP means that the bounds are narrowed by Small to exclude the
7035 -- end-points if this reduces the size.
7037 -- Note that in the Incl case, all we care about is including the
7038 -- end-points. In the Excl case, we want to narrow the bounds as
7039 -- much as permitted by the RM, to give the smallest possible size.
7056 begin
7057 -- First step. Base types are required to be symmetrical. Right
7058 -- now, the base type range is a copy of the first subtype range.
7059 -- This will be corrected before we are done, but right away we
7060 -- need to deal with the case where both bounds are non-negative.
7061 -- In this case, we set the low bound to the negative of the high
7062 -- bound, to make sure that the size is computed to include the
7063 -- required sign. Note that we do not need to worry about the
7064 -- case of both bounds negative, because the sign will be dealt
7065 -- with anyway. Furthermore we can't just go making such a bound
7066 -- symmetrical, since in a twos-complement system, there is an
7067 -- extra negative value which could not be accommodated on the
7068 -- positive side.
7073 then
7078 -- Compute the fudged bounds. If the number is a model number,
7079 -- then we do nothing to include it, but we are allowed to backoff
7080 -- to the next adjacent model number when we exclude it. If it is
7081 -- not a model number then we straddle the two values with the
7082 -- model numbers on either side.
7088 else
7092 -- The low value excluding the end point is Small greater, but
7093 -- we do not do this exclusion if the low value is positive,
7094 -- since it can't help the size and could actually hurt by
7095 -- crossing the high bound.
7100 -- If the value went from negative to zero, then we have the
7101 -- case where Loval_Incl_EP is the model number just below
7102 -- zero, so we want to stick to the negative value for the
7103 -- base type to maintain the condition that the size will
7104 -- include signed values.
7108 then
7112 else
7116 -- Similar processing for upper bound and high value
7122 else
7128 else
7132 -- One further adjustment is needed. In the case of subtypes, we
7133 -- cannot go outside the range of the base type, or we get
7134 -- peculiarities, and the base type range is already set. This
7135 -- only applies to the Incl values, since clearly the Excl values
7136 -- are already as restricted as they are allowed to be.
7143 -- Get size including and excluding end points
7148 -- No need to exclude end-points if it does not reduce size
7158 -- Now we set the actual size to be used. We want to use the
7159 -- bounds fudged up to include the end-points but only if this
7160 -- can be done without violating a specifically given size
7161 -- size clause or causing an unacceptable increase in size.
7163 -- Case of size clause given
7167 -- Use the inclusive size only if it is consistent with
7168 -- the explicitly specified size.
7175 -- If the inclusive size is too large, we try excluding
7176 -- the end-points (will be caught later if does not work).
7178 else
7184 -- Case of size clause not given
7186 else
7187 -- If we have a base type whose corresponding first subtype
7188 -- has an explicit size that is large enough to include our
7189 -- end-points, then do so. There is no point in working hard
7190 -- to get a base type whose size is smaller than the specified
7191 -- size of the first subtype.
7197 then
7202 -- If excluding the end-points makes the size smaller and
7203 -- results in a size of 8,16,32,64, then we take the smaller
7204 -- size. For the 64 case, this is compulsory. For the other
7205 -- cases, it seems reasonable. We like to include end points
7206 -- if we can, but not at the expense of moving to the next
7207 -- natural boundary of size.
7211 then
7216 -- Otherwise we can definitely include the end points
7218 else
7224 -- One pathological case: normally we never fudge a low bound
7225 -- down, since it would seem to increase the size (if it has
7226 -- any effect), but for ranges containing single value, or no
7227 -- values, the high bound can be small too large. Consider:
7229 -- type t is delta 2.0**(-14)
7230 -- range 131072.0 .. 0;
7232 -- That lower bound is *just* outside the range of 32 bits, and
7233 -- does need fudging down in this case. Note that the bounds
7234 -- will always have crossed here, since the high bound will be
7235 -- fudged down if necessary, as in the case of:
7237 -- type t is delta 2.0**(-14)
7238 -- range 131072.0 .. 131072.0;
7240 -- So we detect the situation by looking for crossed bounds,
7241 -- and if the bounds are crossed, and the low bound is greater
7242 -- than zero, we will always back it off by small, since this
7243 -- is completely harmless.
7250 -- And of course, we need to do exactly the same parallel
7251 -- fudge for flat ranges in the negative region.
7264 -- For the decimal case, none of this fudging is required, since there
7265 -- are no end-point problems in the decimal case (the end-points are
7266 -- always included).
7268 else
7272 -- At this stage, the actual size has been calculated and the proper
7273 -- required bounds are stored in the low and high bounds.
7277 Error_Msg_N
7279 Typ);
7283 -- Check size against explicit given size
7289 Error_Msg_NE
7293 else
7297 -- Increase size to next natural boundary if no size clause given
7299 else
7306 else
7314 -- If we have a base type, then expand the bounds so that they extend to
7315 -- the full width of the allocated size in bits, to avoid junk range
7316 -- checks on intermediate computations.
7323 -- Final step is to reanalyze the bounds using the proper type
7324 -- and set the Corresponding_Integer_Value fields of the literals.
7330 -- Resolve with universal fixed if the base type, and the base type if
7331 -- it is a subtype. Note we can't resolve the base type with itself,
7332 -- that would be a reference before definition.
7336 else
7340 -- Set corresponding integer value for bound
7342 Set_Corresponding_Integer_Value
7345 -- Similar processing for high bound
7353 else
7357 Set_Corresponding_Integer_Value
7360 -- Set type of range to correspond to bounds
7364 -- Set Esize to calculated size if not set already
7370 -- Set RM_Size if not already set. If already set, check value
7372 declare
7375 begin
7380 Error_Msg_NE
7385 else
7390 -- Check for shaving
7394 Error_Msg_N
7396 Error_Msg_N
7401 Error_Msg_N
7403 Error_Msg_N
7409 ------------------
7410 -- Freeze_Itype --
7411 ------------------
7416 begin
7425 --------------------------
7426 -- Freeze_Static_Object --
7427 --------------------------
7432 -- Exception raised if the type of a static object cannot be made
7433 -- static. This happens if the type depends on non-global objects.
7436 -- Called to ensure that an expression used as part of a type definition
7437 -- is statically allocatable, which means that the expression type is
7438 -- statically allocatable, and the expression is either static, or a
7439 -- reference to a library level constant.
7442 -- Called to mark a type as static, checking that it is possible
7443 -- to set the type as static. If it is not possible, then the
7444 -- exception Cannot_Be_Static is raised.
7446 -----------------------------
7447 -- Ensure_Expression_Is_SA --
7448 -----------------------------
7453 begin
7465 then
7473 -----------------------
7474 -- Ensure_Type_Is_SA --
7475 -----------------------
7481 begin
7482 -- If type is library level, we are all set
7488 -- We are also OK if the type already marked as statically allocated,
7489 -- which means we processed it before.
7495 -- Mark type as statically allocated
7499 -- Check that it is safe to statically allocate this type
7517 declare
7521 begin
7533 else
7542 then
7561 else
7566 -- Start of processing for Freeze_Static_Object
7568 begin
7571 exception
7574 -- If the object that cannot be static is imported or exported, then
7575 -- issue an error message saying that this object cannot be imported
7576 -- or exported. If it has an address clause it is an overlay in the
7577 -- current partition and the static requirement is not relevant.
7578 -- Do not issue any error message when ignoring rep clauses.
7585 Error_Msg_N
7589 -- Otherwise must be exported, something is wrong if compiler
7590 -- is marking something as statically allocated which cannot be).
7593 Error_Msg_N
7598 -----------------------
7599 -- Freeze_Subprogram --
7600 -----------------------
7606 begin
7607 -- Subprogram may not have an address clause unless it is imported
7611 Error_Msg_N
7618 -- Reset the Pure indication on an imported subprogram unless an
7619 -- explicit Pure_Function pragma was present or the subprogram is an
7620 -- intrinsic. We do this because otherwise it is an insidious error
7621 -- to call a non-pure function from pure unit and have calls
7622 -- mysteriously optimized away. What happens here is that the Import
7623 -- can bypass the normal check to ensure that pure units call only pure
7624 -- subprograms.
7626 -- The reason for the intrinsic exception is that in general, intrinsic
7627 -- functions (such as shifts) are pure anyway. The only exceptions are
7628 -- the intrinsics in GNAT.Source_Info, and that unit is not marked Pure
7629 -- in any case, so no problem arises.
7635 then
7639 -- For non-foreign convention subprograms, this is where we create
7640 -- the extra formals (for accessibility level and constrained bit
7641 -- information). We delay this till the freeze point precisely so
7642 -- that we know the convention.
7648 -- If this is convention Ada and a Valued_Procedure, that's odd
7653 and then Warn_On_Export_Import
7654 then
7655 Error_Msg_N
7660 -- Case of foreign convention
7662 else
7665 -- For foreign conventions, warn about return of unconstrained array
7670 -- If no return type, probably some other error, e.g. a
7671 -- missing full declaration, so ignore.
7676 -- If the return type is generic, we have emitted a warning
7677 -- earlier on, and there is nothing else to check here. Specific
7678 -- instantiations may lead to erroneous behavior.
7683 -- Display warning if returning unconstrained array
7688 -- Check appropriate warning is enabled (should we check for
7689 -- Warnings (Off) on specific entities here, probably so???)
7691 and then Warn_On_Export_Import
7693 -- Exclude the VM case, since return of unconstrained arrays
7694 -- is properly handled in both the JVM and .NET cases.
7697 then
7698 Error_Msg_N
7705 -- If any of the formals for an exported foreign convention
7706 -- subprogram have defaults, then emit an appropriate warning since
7707 -- this is odd (default cannot be used from non-Ada code)
7712 if Warn_On_Export_Import
7714 then
7715 Error_Msg_N
7725 -- Pragma Inline_Always is disallowed for dispatching subprograms
7726 -- because the address of such subprograms is saved in the dispatch
7727 -- table to support dispatching calls, and dispatching calls cannot
7728 -- be inlined. This is consistent with the restriction against using
7729 -- 'Access or 'Address on an Inline_Always subprogram.
7733 then
7734 Error_Msg_N
7738 -- Because of the implicit representation of inherited predefined
7739 -- operators in the front-end, the overriding status of the operation
7740 -- may be affected when a full view of a type is analyzed, and this is
7741 -- not captured by the analysis of the corresponding type declaration.
7742 -- Therefore the correctness of a not-overriding indicator must be
7743 -- rechecked when the subprogram is frozen.
7747 then
7752 ----------------------
7753 -- Is_Fully_Defined --
7754 ----------------------
7757 begin
7766 then
7767 -- Verify that the record type has no components with private types
7768 -- without completion.
7770 declare
7773 begin
7785 -- For the designated type of an access to subprogram, all types in
7786 -- the profile must be fully defined.
7789 declare
7792 begin
7805 else
7811 ---------------------------------
7812 -- Process_Default_Expressions --
7813 ---------------------------------
7815 procedure Process_Default_Expressions
7818 is
7825 begin
7828 -- A subprogram instance and its associated anonymous subprogram share
7829 -- their signature. The default expression functions are defined in the
7830 -- wrapper packages for the anonymous subprogram, and should not be
7831 -- generated again for the instance.
7836 then
7844 -- We work with a copy of the default expression because we
7845 -- do not want to disturb the original, since this would mess
7846 -- up the conformance checking.
7850 -- The analysis of the expression may generate insert actions,
7851 -- which of course must not be executed. We wrap those actions
7852 -- in a procedure that is not called, and later on eliminated.
7853 -- The following cases have no side-effects, and are analyzed
7854 -- directly.
7858 N_Integer_Literal,
7859 N_Character_Literal,
7860 N_String_Literal,
7861 N_Real_Literal)
7865 then
7866 -- If there is no default function, we must still do a full
7867 -- analyze call on the default value, to ensure that all error
7868 -- checks are performed, e.g. those associated with static
7869 -- evaluation. Note: this branch will always be taken if the
7870 -- analyzer is turned off (but we still need the error checks).
7872 -- Note: the setting of parent here is to meet the requirement
7873 -- that we can only analyze the expression while attached to
7874 -- the tree. Really the requirement is that the parent chain
7875 -- be set, we don't actually need to be in the tree.
7880 -- Default expressions are resolved with their own type if the
7881 -- context is generic, to avoid anomalies with private types.
7885 else
7889 -- If that resolved expression will raise constraint error,
7890 -- then flag the default value as raising constraint error.
7891 -- This allows a proper error message on the calls.
7897 -- If the default is a parameterless call, we use the name of
7898 -- the called function directly, and there is no body to build.
7902 then
7905 -- Else construct and analyze the body of a wrapper procedure
7906 -- that contains an object declaration to hold the expression.
7907 -- Given that this is done only to complete the analysis, it
7908 -- simpler to build a procedure than a function which might
7909 -- involve secondary stack expansion.
7911 else
7914 Dbody :=
7916 Specification =>
7923 Object_Definition =>
7927 Handled_Statement_Sequence =>
7944 ----------------------------------------
7945 -- Set_Component_Alignment_If_Not_Set --
7946 ----------------------------------------
7949 begin
7950 -- Ignore if not base type, subtypes don't need anything
7956 -- Do not override existing representation
7967 else
7968 Set_Component_Alignment
7974 --------------------------
7975 -- Set_SSO_From_Default --
7976 --------------------------
7981 begin
7982 -- Set default SSO for an array or record base type, except in case of
7983 -- a type extension (which always inherits the SSO of its parent type).
7990 then
7991 Reversed :=
7993 or else
7998 -- For a record type, if bit order is specified explicitly,
7999 -- then do not set SSO from default if not consistent. Note that
8000 -- we do not want to look at a Bit_Order attribute definition
8001 -- for a parent: if we were to inherit Bit_Order, then both
8002 -- SSO_Set_*_By_Default flags would have been cleared already
8003 -- (by Inherit_Aspects_At_Freeze_Point).
8005 and then not
8007 and then
8010 then
8011 -- If flags cause reverse storage order, then set the result. Note
8012 -- that we would have ignored the pragma setting the non default
8013 -- storage order in any case, hence the assertion at this point.
8015 pragma Assert
8020 -- For a record type, also set reversed bit order. Note: if a bit
8021 -- order has been specified explicitly, then this is a no-op.
8030 ------------------
8031 -- Undelay_Type --
8032 ------------------
8035 begin
8039 -- Since we don't want T to have a Freeze_Node, we don't want its
8040 -- Full_View or Corresponding_Record_Type to have one either.
8042 -- ??? Fundamentally, this whole handling is unpleasant. What we really
8043 -- want is to be sure that for an Itype that's part of record R and is a
8044 -- subtype of type T, that it's frozen after the later of the freeze
8045 -- points of R and T. We have no way of doing that directly, so what we
8046 -- do is force most such Itypes to be frozen as part of freezing R via
8047 -- this procedure and only delay the ones that need to be delayed
8048 -- (mostly the designated types of access types that are defined as part
8049 -- of the record).
8055 then
8063 then
8068 ------------------
8069 -- Warn_Overlay --
8070 ------------------
8072 procedure Warn_Overlay
8076 is
8078 -- The object to which the address clause applies
8084 begin
8085 -- No warning if address clause overlay warnings are off
8091 -- No warning if there is an explicit initialization
8099 -- We only give the warning for non-imported entities of a type for
8100 -- which a non-null base init proc is defined, or for objects of access
8101 -- types with implicit null initialization, or when Normalize_Scalars
8102 -- applies and the type is scalar or a string type (the latter being
8103 -- tested for because predefined String types are initialized by inline
8104 -- code rather than by an init_proc). Note that we do not give the
8105 -- warning for Initialize_Scalars, since we suppressed initialization
8106 -- in this case. Also, do not warn if Suppress_Initialization is set.
8116 then
8119 then
8124 then
8131 then
8138 -- A function call (most likely to To_Address) is probably not an
8139 -- overlay, so skip warning. Ditto if the function call was inlined
8140 -- and transformed into an entity.
8146 -- If a pragma Import follows, we assume that it is for the current
8147 -- target of the address clause, and skip the warning. There may be
8148 -- a source pragma or an aspect that specifies import and generates
8149 -- the corresponding pragma. These will indicate that the entity is
8150 -- imported and that is checked above so that the spurious warning
8151 -- (generated when the entity is frozen) will be suppressed. The
8152 -- pragma may be attached to the aspect, so it is not yet a list
8153 -- member.
8161 then
8166 -- Otherwise give warning message
8170 Error_Msg_N
8172 Nam);
8173 else
8174 Error_Msg_N
8176 Nam);
8179 -- Add friendly warning if initialization comes from a packed array
8180 -- component.
8183 declare
8186 begin
8191 then
8195 then
8196 Error_Msg_NE
8201 else
8208 Error_Msg_N
8211 Nam);