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Diffstat (limited to 'gcc-4.4.3/gcc/ada/sem_elab.adb')
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diff --git a/gcc-4.4.3/gcc/ada/sem_elab.adb b/gcc-4.4.3/gcc/ada/sem_elab.adb deleted file mode 100644 index 340659911..000000000 --- a/gcc-4.4.3/gcc/ada/sem_elab.adb +++ /dev/null @@ -1,3177 +0,0 @@ ------------------------------------------------------------------------------- --- -- --- GNAT COMPILER COMPONENTS -- --- -- --- S E M _ E L A B -- --- -- --- B o d y -- --- -- --- Copyright (C) 1997-2008, Free Software Foundation, Inc. -- --- -- --- GNAT is free software; you can redistribute it and/or modify it under -- --- terms of the GNU General Public License as published by the Free Soft- -- --- ware Foundation; either version 3, or (at your option) any later ver- -- --- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- --- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- --- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- --- for more details. You should have received a copy of the GNU General -- --- Public License distributed with GNAT; see file COPYING3. If not, go to -- --- http://www.gnu.org/licenses for a complete copy of the license. -- --- -- --- GNAT was originally developed by the GNAT team at New York University. -- --- Extensive contributions were provided by Ada Core Technologies Inc. -- --- -- ------------------------------------------------------------------------------- - -with Atree; use Atree; -with Checks; use Checks; -with Debug; use Debug; -with Einfo; use Einfo; -with Elists; use Elists; -with Errout; use Errout; -with Exp_Tss; use Exp_Tss; -with Exp_Util; use Exp_Util; -with Expander; use Expander; -with Fname; use Fname; -with Lib; use Lib; -with Lib.Load; use Lib.Load; -with Namet; use Namet; -with Nlists; use Nlists; -with Nmake; use Nmake; -with Opt; use Opt; -with Output; use Output; -with Restrict; use Restrict; -with Rident; use Rident; -with Sem; use Sem; -with Sem_Cat; use Sem_Cat; -with Sem_Ch7; use Sem_Ch7; -with Sem_Ch8; use Sem_Ch8; -with Sem_Res; use Sem_Res; -with Sem_Util; use Sem_Util; -with Sinfo; use Sinfo; -with Sinput; use Sinput; -with Snames; use Snames; -with Stand; use Stand; -with Table; -with Tbuild; use Tbuild; -with Uname; use Uname; - -package body Sem_Elab is - - -- The following table records the recursive call chain for output in the - -- Output routine. Each entry records the call node and the entity of the - -- called routine. The number of entries in the table (i.e. the value of - -- Elab_Call.Last) indicates the current depth of recursion and is used to - -- identify the outer level. - - type Elab_Call_Entry is record - Cloc : Source_Ptr; - Ent : Entity_Id; - end record; - - package Elab_Call is new Table.Table ( - Table_Component_Type => Elab_Call_Entry, - Table_Index_Type => Int, - Table_Low_Bound => 1, - Table_Initial => 50, - Table_Increment => 100, - Table_Name => "Elab_Call"); - - -- This table is initialized at the start of each outer level call. It - -- holds the entities for all subprograms that have been examined for this - -- particular outer level call, and is used to prevent both infinite - -- recursion, and useless reanalysis of bodies already seen - - package Elab_Visited is new Table.Table ( - Table_Component_Type => Entity_Id, - Table_Index_Type => Int, - Table_Low_Bound => 1, - Table_Initial => 200, - Table_Increment => 100, - Table_Name => "Elab_Visited"); - - -- This table stores calls to Check_Internal_Call that are delayed - -- until all generics are instantiated, and in particular that all - -- generic bodies have been inserted. We need to delay, because we - -- need to be able to look through the inserted bodies. - - type Delay_Element is record - N : Node_Id; - -- The parameter N from the call to Check_Internal_Call. Note that - -- this node may get rewritten over the delay period by expansion - -- in the call case (but not in the instantiation case). - - E : Entity_Id; - -- The parameter E from the call to Check_Internal_Call - - Orig_Ent : Entity_Id; - -- The parameter Orig_Ent from the call to Check_Internal_Call - - Curscop : Entity_Id; - -- The current scope of the call. This is restored when we complete - -- the delayed call, so that we do this in the right scope. - - From_Elab_Code : Boolean; - -- Save indication of whether this call is from elaboration code - - Outer_Scope : Entity_Id; - -- Save scope of outer level call - end record; - - package Delay_Check is new Table.Table ( - Table_Component_Type => Delay_Element, - Table_Index_Type => Int, - Table_Low_Bound => 1, - Table_Initial => 1000, - Table_Increment => 100, - Table_Name => "Delay_Check"); - - C_Scope : Entity_Id; - -- Top level scope of current scope. Compute this only once at the outer - -- level, i.e. for a call to Check_Elab_Call from outside this unit. - - Outer_Level_Sloc : Source_Ptr; - -- Save Sloc value for outer level call node for comparisons of source - -- locations. A body is too late if it appears after the *outer* level - -- call, not the particular call that is being analyzed. - - From_Elab_Code : Boolean; - -- This flag shows whether the outer level call currently being examined - -- is or is not in elaboration code. We are only interested in calls to - -- routines in other units if this flag is True. - - In_Task_Activation : Boolean := False; - -- This flag indicates whether we are performing elaboration checks on - -- task procedures, at the point of activation. If true, we do not trace - -- internal calls in these procedures, because all local bodies are known - -- to be elaborated. - - Delaying_Elab_Checks : Boolean := True; - -- This is set True till the compilation is complete, including the - -- insertion of all instance bodies. Then when Check_Elab_Calls is called, - -- the delay table is used to make the delayed calls and this flag is reset - -- to False, so that the calls are processed - - ----------------------- - -- Local Subprograms -- - ----------------------- - - -- Note: Outer_Scope in all following specs represents the scope of - -- interest of the outer level call. If it is set to Standard_Standard, - -- then it means the outer level call was at elaboration level, and that - -- thus all calls are of interest. If it was set to some other scope, - -- then the original call was an inner call, and we are not interested - -- in calls that go outside this scope. - - procedure Activate_Elaborate_All_Desirable (N : Node_Id; U : Entity_Id); - -- Analysis of construct N shows that we should set Elaborate_All_Desirable - -- for the WITH clause for unit U (which will always be present). A special - -- case is when N is a function or procedure instantiation, in which case - -- it is sufficient to set Elaborate_Desirable, since in this case there is - -- no possibility of transitive elaboration issues. - - procedure Check_A_Call - (N : Node_Id; - E : Entity_Id; - Outer_Scope : Entity_Id; - Inter_Unit_Only : Boolean; - Generate_Warnings : Boolean := True); - -- This is the internal recursive routine that is called to check for a - -- possible elaboration error. The argument N is a subprogram call or - -- generic instantiation to be checked, and E is the entity of the called - -- subprogram, or instantiated generic unit. The flag Outer_Scope is the - -- outer level scope for the original call. Inter_Unit_Only is set if the - -- call is only to be checked in the case where it is to another unit (and - -- skipped if within a unit). Generate_Warnings is set to False to suppress - -- warning messages about missing pragma Elaborate_All's. These messages - -- are not wanted for inner calls in the dynamic model. - - procedure Check_Bad_Instantiation (N : Node_Id); - -- N is a node for an instantiation (if called with any other node kind, - -- Check_Bad_Instantiation ignores the call). This subprogram checks for - -- the special case of a generic instantiation of a generic spec in the - -- same declarative part as the instantiation where a body is present and - -- has not yet been seen. This is an obvious error, but needs to be checked - -- specially at the time of the instantiation, since it is a case where we - -- cannot insert the body anywhere. If this case is detected, warnings are - -- generated, and a raise of Program_Error is inserted. In addition any - -- subprograms in the generic spec are stubbed, and the Bad_Instantiation - -- flag is set on the instantiation node. The caller in Sem_Ch12 uses this - -- flag as an indication that no attempt should be made to insert an - -- instance body. - - procedure Check_Internal_Call - (N : Node_Id; - E : Entity_Id; - Outer_Scope : Entity_Id; - Orig_Ent : Entity_Id); - -- N is a function call or procedure statement call node and E is the - -- entity of the called function, which is within the current compilation - -- unit (where subunits count as part of the parent). This call checks if - -- this call, or any call within any accessed body could cause an ABE, and - -- if so, outputs a warning. Orig_Ent differs from E only in the case of - -- renamings, and points to the original name of the entity. This is used - -- for error messages. Outer_Scope is the outer level scope for the - -- original call. - - procedure Check_Internal_Call_Continue - (N : Node_Id; - E : Entity_Id; - Outer_Scope : Entity_Id; - Orig_Ent : Entity_Id); - -- The processing for Check_Internal_Call is divided up into two phases, - -- and this represents the second phase. The second phase is delayed if - -- Delaying_Elab_Calls is set to True. In this delayed case, the first - -- phase makes an entry in the Delay_Check table, which is processed when - -- Check_Elab_Calls is called. N, E and Orig_Ent are as for the call to - -- Check_Internal_Call. Outer_Scope is the outer level scope for the - -- original call. - - procedure Set_Elaboration_Constraint - (Call : Node_Id; - Subp : Entity_Id; - Scop : Entity_Id); - -- The current unit U may depend semantically on some unit P which is not - -- in the current context. If there is an elaboration call that reaches P, - -- we need to indicate that P requires an Elaborate_All, but this is not - -- effective in U's ali file, if there is no with_clause for P. In this - -- case we add the Elaborate_All on the unit Q that directly or indirectly - -- makes P available. This can happen in two cases: - -- - -- a) Q declares a subtype of a type declared in P, and the call is an - -- initialization call for an object of that subtype. - -- - -- b) Q declares an object of some tagged type whose root type is - -- declared in P, and the initialization call uses object notation on - -- that object to reach a primitive operation or a classwide operation - -- declared in P. - -- - -- If P appears in the context of U, the current processing is correct. - -- Otherwise we must identify these two cases to retrieve Q and place the - -- Elaborate_All_Desirable on it. - - function Has_Generic_Body (N : Node_Id) return Boolean; - -- N is a generic package instantiation node, and this routine determines - -- if this package spec does in fact have a generic body. If so, then - -- True is returned, otherwise False. Note that this is not at all the - -- same as checking if the unit requires a body, since it deals with - -- the case of optional bodies accurately (i.e. if a body is optional, - -- then it looks to see if a body is actually present). Note: this - -- function can only do a fully correct job if in generating code mode - -- where all bodies have to be present. If we are operating in semantics - -- check only mode, then in some cases of optional bodies, a result of - -- False may incorrectly be given. In practice this simply means that - -- some cases of warnings for incorrect order of elaboration will only - -- be given when generating code, which is not a big problem (and is - -- inevitable, given the optional body semantics of Ada). - - procedure Insert_Elab_Check (N : Node_Id; C : Node_Id := Empty); - -- Given code for an elaboration check (or unconditional raise if the check - -- is not needed), inserts the code in the appropriate place. N is the call - -- or instantiation node for which the check code is required. C is the - -- test whose failure triggers the raise. - - procedure Output_Calls (N : Node_Id); - -- Outputs chain of calls stored in the Elab_Call table. The caller has - -- already generated the main warning message, so the warnings generated - -- are all continuation messages. The argument is the call node at which - -- the messages are to be placed. - - function Same_Elaboration_Scope (Scop1, Scop2 : Entity_Id) return Boolean; - -- Given two scopes, determine whether they are the same scope from an - -- elaboration point of view, i.e. packages and blocks are ignored. - - procedure Set_C_Scope; - -- On entry C_Scope is set to some scope. On return, C_Scope is reset - -- to be the enclosing compilation unit of this scope. - - function Spec_Entity (E : Entity_Id) return Entity_Id; - -- Given a compilation unit entity, if it is a spec entity, it is returned - -- unchanged. If it is a body entity, then the spec for the corresponding - -- spec is returned - - procedure Supply_Bodies (N : Node_Id); - -- Given a node, N, that is either a subprogram declaration or a package - -- declaration, this procedure supplies dummy bodies for the subprogram - -- or for all subprograms in the package. If the given node is not one - -- of these two possibilities, then Supply_Bodies does nothing. The - -- dummy body contains a single Raise statement. - - procedure Supply_Bodies (L : List_Id); - -- Calls Supply_Bodies for all elements of the given list L - - function Within (E1, E2 : Entity_Id) return Boolean; - -- Given two scopes E1 and E2, returns True if E1 is equal to E2, or is one - -- of its contained scopes, False otherwise. - - function Within_Elaborate_All (E : Entity_Id) return Boolean; - -- Before emitting a warning on a scope E for a missing elaborate_all, - -- check whether E may be in the context of a directly visible unit U to - -- which the pragma applies. This prevents spurious warnings when the - -- called entity is renamed within U. - - -------------------------------------- - -- Activate_Elaborate_All_Desirable -- - -------------------------------------- - - procedure Activate_Elaborate_All_Desirable (N : Node_Id; U : Entity_Id) is - UN : constant Unit_Number_Type := Get_Code_Unit (N); - CU : constant Node_Id := Cunit (UN); - UE : constant Entity_Id := Cunit_Entity (UN); - Unm : constant Unit_Name_Type := Unit_Name (UN); - CI : constant List_Id := Context_Items (CU); - Itm : Node_Id; - Ent : Entity_Id; - - procedure Add_To_Context_And_Mark (Itm : Node_Id); - -- This procedure is called when the elaborate indication must be - -- applied to a unit not in the context of the referencing unit. The - -- unit gets added to the context as an implicit with. - - function In_Withs_Of (UEs : Entity_Id) return Boolean; - -- UEs is the spec entity of a unit. If the unit to be marked is - -- in the context item list of this unit spec, then the call returns - -- True and Itm is left set to point to the relevant N_With_Clause node. - - procedure Set_Elab_Flag (Itm : Node_Id); - -- Sets Elaborate_[All_]Desirable as appropriate on Itm - - ----------------------------- - -- Add_To_Context_And_Mark -- - ----------------------------- - - procedure Add_To_Context_And_Mark (Itm : Node_Id) is - CW : constant Node_Id := - Make_With_Clause (Sloc (Itm), - Name => Name (Itm)); - - begin - Set_Library_Unit (CW, Library_Unit (Itm)); - Set_Implicit_With (CW, True); - - -- Set elaborate all desirable on copy and then append the copy to - -- the list of body with's and we are done. - - Set_Elab_Flag (CW); - Append_To (CI, CW); - end Add_To_Context_And_Mark; - - ----------------- - -- In_Withs_Of -- - ----------------- - - function In_Withs_Of (UEs : Entity_Id) return Boolean is - UNs : constant Unit_Number_Type := Get_Source_Unit (UEs); - CUs : constant Node_Id := Cunit (UNs); - CIs : constant List_Id := Context_Items (CUs); - - begin - Itm := First (CIs); - while Present (Itm) loop - if Nkind (Itm) = N_With_Clause then - Ent := - Cunit_Entity (Get_Cunit_Unit_Number (Library_Unit (Itm))); - - if U = Ent then - return True; - end if; - end if; - - Next (Itm); - end loop; - - return False; - end In_Withs_Of; - - ------------------- - -- Set_Elab_Flag -- - ------------------- - - procedure Set_Elab_Flag (Itm : Node_Id) is - begin - if Nkind (N) in N_Subprogram_Instantiation then - Set_Elaborate_Desirable (Itm); - else - Set_Elaborate_All_Desirable (Itm); - end if; - end Set_Elab_Flag; - - -- Start of processing for Activate_Elaborate_All_Desirable - - begin - -- Do not set binder indication if expansion is disabled, as when - -- compiling a generic unit. - - if not Expander_Active then - return; - end if; - - Itm := First (CI); - while Present (Itm) loop - if Nkind (Itm) = N_With_Clause then - Ent := Cunit_Entity (Get_Cunit_Unit_Number (Library_Unit (Itm))); - - -- If we find it, then mark elaborate all desirable and return - - if U = Ent then - Set_Elab_Flag (Itm); - return; - end if; - end if; - - Next (Itm); - end loop; - - -- If we fall through then the with clause is not present in the - -- current unit. One legitimate possibility is that the with clause - -- is present in the spec when we are a body. - - if Is_Body_Name (Unm) - and then In_Withs_Of (Spec_Entity (UE)) - then - Add_To_Context_And_Mark (Itm); - return; - end if; - - -- Similarly, we may be in the spec or body of a child unit, where - -- the unit in question is with'ed by some ancestor of the child unit. - - if Is_Child_Name (Unm) then - declare - Pkg : Entity_Id; - - begin - Pkg := UE; - loop - Pkg := Scope (Pkg); - exit when Pkg = Standard_Standard; - - if In_Withs_Of (Pkg) then - Add_To_Context_And_Mark (Itm); - return; - end if; - end loop; - end; - end if; - - -- Here if we do not find with clause on spec or body. We just ignore - -- this case, it means that the elaboration involves some other unit - -- than the unit being compiled, and will be caught elsewhere. - - null; - end Activate_Elaborate_All_Desirable; - - ------------------ - -- Check_A_Call -- - ------------------ - - procedure Check_A_Call - (N : Node_Id; - E : Entity_Id; - Outer_Scope : Entity_Id; - Inter_Unit_Only : Boolean; - Generate_Warnings : Boolean := True) - is - Loc : constant Source_Ptr := Sloc (N); - Ent : Entity_Id; - Decl : Node_Id; - - E_Scope : Entity_Id; - -- Top level scope of entity for called subprogram. This value includes - -- following renamings and derivations, so this scope can be in a - -- non-visible unit. This is the scope that is to be investigated to - -- see whether an elaboration check is required. - - W_Scope : Entity_Id; - -- Top level scope of directly called entity for subprogram. This - -- differs from E_Scope in the case where renamings or derivations - -- are involved, since it does not follow these links. W_Scope is - -- generally in a visible unit, and it is this scope that may require - -- an Elaborate_All. However, there are some cases (initialization - -- calls and calls involving object notation) where W_Scope might not - -- be in the context of the current unit, and there is an intermediate - -- package that is, in which case the Elaborate_All has to be placed - -- on this intermediate package. These special cases are handled in - -- Set_Elaboration_Constraint. - - Body_Acts_As_Spec : Boolean; - -- Set to true if call is to body acting as spec (no separate spec) - - Inst_Case : constant Boolean := Nkind (N) in N_Generic_Instantiation; - -- Indicates if we have instantiation case - - Caller_Unit_Internal : Boolean; - Callee_Unit_Internal : Boolean; - - Inst_Caller : Source_Ptr; - Inst_Callee : Source_Ptr; - - Unit_Caller : Unit_Number_Type; - Unit_Callee : Unit_Number_Type; - - Cunit_SC : Boolean := False; - -- Set to suppress dynamic elaboration checks where one of the - -- enclosing scopes has Elaboration_Checks_Suppressed set, or else - -- if a pragma Elaborate (_All) applies to that scope, in which case - -- warnings on the scope are also suppressed. For the internal case, - -- we ignore this flag. - - begin - -- If the call is known to be within a local Suppress Elaboration - -- pragma, nothing to check. This can happen in task bodies. - - if (Nkind (N) = N_Function_Call - or else Nkind (N) = N_Procedure_Call_Statement) - and then No_Elaboration_Check (N) - then - return; - end if; - - -- Go to parent for derived subprogram, or to original subprogram in the - -- case of a renaming (Alias covers both these cases). - - Ent := E; - loop - if (Suppress_Elaboration_Warnings (Ent) - or else Elaboration_Checks_Suppressed (Ent)) - and then (Inst_Case or else No (Alias (Ent))) - then - return; - end if; - - -- Nothing to do for imported entities - - if Is_Imported (Ent) then - return; - end if; - - exit when Inst_Case or else No (Alias (Ent)); - Ent := Alias (Ent); - end loop; - - Decl := Unit_Declaration_Node (Ent); - - if Nkind (Decl) = N_Subprogram_Body then - Body_Acts_As_Spec := True; - - elsif Nkind (Decl) = N_Subprogram_Declaration - or else Nkind (Decl) = N_Subprogram_Body_Stub - or else Inst_Case - then - Body_Acts_As_Spec := False; - - -- If we have none of an instantiation, subprogram body or - -- subprogram declaration, then it is not a case that we want - -- to check. (One case is a call to a generic formal subprogram, - -- where we do not want the check in the template). - - else - return; - end if; - - E_Scope := Ent; - loop - if Elaboration_Checks_Suppressed (E_Scope) - or else Suppress_Elaboration_Warnings (E_Scope) - then - Cunit_SC := True; - end if; - - -- Exit when we get to compilation unit, not counting subunits - - exit when Is_Compilation_Unit (E_Scope) - and then (Is_Child_Unit (E_Scope) - or else Scope (E_Scope) = Standard_Standard); - - -- If we did not find a compilation unit, other than standard, - -- then nothing to check (happens in some instantiation cases) - - if E_Scope = Standard_Standard then - return; - - -- Otherwise move up a scope looking for compilation unit - - else - E_Scope := Scope (E_Scope); - end if; - end loop; - - -- No checks needed for pure or preelaborated compilation units - - if Is_Pure (E_Scope) - or else Is_Preelaborated (E_Scope) - then - return; - end if; - - -- If the generic entity is within a deeper instance than we are, then - -- either the instantiation to which we refer itself caused an ABE, in - -- which case that will be handled separately, or else we know that the - -- body we need appears as needed at the point of the instantiation. - -- However, this assumption is only valid if we are in static mode. - - if not Dynamic_Elaboration_Checks - and then Instantiation_Depth (Sloc (Ent)) > - Instantiation_Depth (Sloc (N)) - then - return; - end if; - - -- Do not give a warning for a package with no body - - if Ekind (Ent) = E_Generic_Package - and then not Has_Generic_Body (N) - then - return; - end if; - - -- Case of entity is not in current unit (i.e. with'ed unit case) - - if E_Scope /= C_Scope then - - -- We are only interested in such calls if the outer call was from - -- elaboration code, or if we are in Dynamic_Elaboration_Checks mode. - - if not From_Elab_Code and then not Dynamic_Elaboration_Checks then - return; - end if; - - -- Nothing to do if some scope said that no checks were required - - if Cunit_SC then - return; - end if; - - -- Nothing to do for a generic instance, because in this case the - -- checking was at the point of instantiation of the generic However, - -- this shortcut is only applicable in static mode. - - if Is_Generic_Instance (Ent) and not Dynamic_Elaboration_Checks then - return; - end if; - - -- Nothing to do if subprogram with no separate spec. However, a - -- call to Deep_Initialize may result in a call to a user-defined - -- Initialize procedure, which imposes a body dependency. This - -- happens only if the type is controlled and the Initialize - -- procedure is not inherited. - - if Body_Acts_As_Spec then - if Is_TSS (Ent, TSS_Deep_Initialize) then - declare - Typ : Entity_Id; - Init : Entity_Id; - begin - Typ := Etype (Next_Formal (First_Formal (Ent))); - - if not Is_Controlled (Typ) then - return; - else - Init := Find_Prim_Op (Typ, Name_Initialize); - - if Comes_From_Source (Init) then - Ent := Init; - else - return; - end if; - end if; - end; - - else - return; - end if; - end if; - - -- Check cases of internal units - - Callee_Unit_Internal := - Is_Internal_File_Name - (Unit_File_Name (Get_Source_Unit (E_Scope))); - - -- Do not give a warning if the with'ed unit is internal - -- and this is the generic instantiation case (this saves a - -- lot of hassle dealing with the Text_IO special child units) - - if Callee_Unit_Internal and Inst_Case then - return; - end if; - - if C_Scope = Standard_Standard then - Caller_Unit_Internal := False; - else - Caller_Unit_Internal := - Is_Internal_File_Name - (Unit_File_Name (Get_Source_Unit (C_Scope))); - end if; - - -- Do not give a warning if the with'ed unit is internal - -- and the caller is not internal (since the binder always - -- elaborates internal units first). - - if Callee_Unit_Internal and (not Caller_Unit_Internal) then - return; - end if; - - -- For now, if debug flag -gnatdE is not set, do no checking for - -- one internal unit withing another. This fixes the problem with - -- the sgi build and storage errors. To be resolved later ??? - - if (Callee_Unit_Internal and Caller_Unit_Internal) - and then not Debug_Flag_EE - then - return; - end if; - - if Is_TSS (E, TSS_Deep_Initialize) then - Ent := E; - end if; - - -- If the call is in an instance, and the called entity is not - -- defined in the same instance, then the elaboration issue - -- focuses around the unit containing the template, it is - -- this unit which requires an Elaborate_All. - - -- However, if we are doing dynamic elaboration, we need to - -- chase the call in the usual manner. - - -- We do not handle the case of calling a generic formal correctly - -- in the static case. See test 4703-004 to explore this gap ??? - - Inst_Caller := Instantiation (Get_Source_File_Index (Sloc (N))); - Inst_Callee := Instantiation (Get_Source_File_Index (Sloc (Ent))); - - if Inst_Caller = No_Location then - Unit_Caller := No_Unit; - else - Unit_Caller := Get_Source_Unit (N); - end if; - - if Inst_Callee = No_Location then - Unit_Callee := No_Unit; - else - Unit_Callee := Get_Source_Unit (Ent); - end if; - - if Unit_Caller /= No_Unit - and then Unit_Callee /= Unit_Caller - and then not Dynamic_Elaboration_Checks - then - E_Scope := Spec_Entity (Cunit_Entity (Unit_Caller)); - - -- If we don't get a spec entity, just ignore call. Not quite - -- clear why this check is necessary. ??? - - if No (E_Scope) then - return; - end if; - - -- Otherwise step to enclosing compilation unit - - while not Is_Compilation_Unit (E_Scope) loop - E_Scope := Scope (E_Scope); - end loop; - - -- For the case N is not an instance, or a call within instance, we - -- recompute E_Scope for the error message, since we do NOT want to - -- go to the unit which has the ultimate declaration in the case of - -- renaming and derivation and we also want to go to the generic unit - -- in the case of an instance, and no further. - - else - -- Loop to carefully follow renamings and derivations one step - -- outside the current unit, but not further. - - if not Inst_Case - and then Present (Alias (Ent)) - then - E_Scope := Alias (Ent); - else - E_Scope := Ent; - end if; - - loop - while not Is_Compilation_Unit (E_Scope) loop - E_Scope := Scope (E_Scope); - end loop; - - -- If E_Scope is the same as C_Scope, it means that there - -- definitely was a local renaming or derivation, and we - -- are not yet out of the current unit. - - exit when E_Scope /= C_Scope; - Ent := Alias (Ent); - E_Scope := Ent; - - -- If no alias, there is a previous error - - if No (Ent) then - return; - end if; - end loop; - end if; - - if Within_Elaborate_All (E_Scope) then - return; - end if; - - -- Find top level scope for called entity (not following renamings - -- or derivations). This is where the Elaborate_All will go if it - -- is needed. We start with the called entity, except in the case - -- of an initialization procedure outside the current package, where - -- the init proc is in the root package, and we start from the entity - -- of the name in the call. - - if Is_Entity_Name (Name (N)) - and then Is_Init_Proc (Entity (Name (N))) - and then not In_Same_Extended_Unit (N, Entity (Name (N))) - then - W_Scope := Scope (Entity (Name (N))); - else - W_Scope := E; - end if; - - while not Is_Compilation_Unit (W_Scope) loop - W_Scope := Scope (W_Scope); - end loop; - - -- Now check if an elaborate_all (or dynamic check) is needed - - if not Suppress_Elaboration_Warnings (Ent) - and then not Elaboration_Checks_Suppressed (Ent) - and then not Suppress_Elaboration_Warnings (E_Scope) - and then not Elaboration_Checks_Suppressed (E_Scope) - and then Elab_Warnings - and then Generate_Warnings - then - Generate_Elab_Warnings : declare - procedure Elab_Warning - (Msg_D : String; - Msg_S : String; - Ent : Node_Or_Entity_Id); - -- Generate a call to Error_Msg_NE with parameters Msg_D or - -- Msg_S (for dynamic or static elaboration model), N and Ent. - - ------------------ - -- Elab_Warning -- - ------------------ - - procedure Elab_Warning - (Msg_D : String; - Msg_S : String; - Ent : Node_Or_Entity_Id) - is - begin - if Dynamic_Elaboration_Checks then - Error_Msg_NE (Msg_D, N, Ent); - else - Error_Msg_NE (Msg_S, N, Ent); - end if; - end Elab_Warning; - - -- Start of processing for Generate_Elab_Warnings - - begin - if Inst_Case then - Elab_Warning - ("instantiation of& may raise Program_Error?", - "info: instantiation of& during elaboration?", Ent); - - else - if Nkind (Name (N)) in N_Has_Entity - and then Is_Init_Proc (Entity (Name (N))) - and then Comes_From_Source (Ent) - then - Elab_Warning - ("implicit call to & may raise Program_Error?", - "info: implicit call to & during elaboration?", - Ent); - - else - Elab_Warning - ("call to & may raise Program_Error?", - "info: call to & during elaboration?", - Ent); - end if; - end if; - - Error_Msg_Qual_Level := Nat'Last; - - if Nkind (N) in N_Subprogram_Instantiation then - Elab_Warning - ("\missing pragma Elaborate for&?", - "\info: implicit pragma Elaborate for& generated?", - W_Scope); - else - Elab_Warning - ("\missing pragma Elaborate_All for&?", - "\info: implicit pragma Elaborate_All for & generated?", - W_Scope); - end if; - end Generate_Elab_Warnings; - - Error_Msg_Qual_Level := 0; - Output_Calls (N); - - -- Set flag to prevent further warnings for same unit unless in - -- All_Errors_Mode. - - if not All_Errors_Mode and not Dynamic_Elaboration_Checks then - Set_Suppress_Elaboration_Warnings (W_Scope, True); - end if; - end if; - - -- Check for runtime elaboration check required - - if Dynamic_Elaboration_Checks then - if not Elaboration_Checks_Suppressed (Ent) - and then not Elaboration_Checks_Suppressed (W_Scope) - and then not Elaboration_Checks_Suppressed (E_Scope) - and then not Cunit_SC - then - -- Runtime elaboration check required. Generate check of the - -- elaboration Boolean for the unit containing the entity. - - -- Note that for this case, we do check the real unit (the one - -- from following renamings, since that is the issue!) - - -- Could this possibly miss a useless but required PE??? - - Insert_Elab_Check (N, - Make_Attribute_Reference (Loc, - Attribute_Name => Name_Elaborated, - Prefix => - New_Occurrence_Of - (Spec_Entity (E_Scope), Loc))); - end if; - - -- Case of static elaboration model - - else - -- Do not do anything if elaboration checks suppressed. Note that - -- we check Ent here, not E, since we want the real entity for the - -- body to see if checks are suppressed for it, not the dummy - -- entry for renamings or derivations. - - if Elaboration_Checks_Suppressed (Ent) - or else Elaboration_Checks_Suppressed (E_Scope) - or else Elaboration_Checks_Suppressed (W_Scope) - then - null; - - -- Here we need to generate an implicit elaborate all - - else - -- Generate elaborate_all warning unless suppressed - - if (Elab_Warnings and Generate_Warnings and not Inst_Case) - and then not Suppress_Elaboration_Warnings (Ent) - and then not Suppress_Elaboration_Warnings (E_Scope) - and then not Suppress_Elaboration_Warnings (W_Scope) - then - Error_Msg_Node_2 := W_Scope; - Error_Msg_NE - ("call to& in elaboration code " & - "requires pragma Elaborate_All on&?", N, E); - end if; - - -- Set indication for binder to generate Elaborate_All - - Set_Elaboration_Constraint (N, E, W_Scope); - end if; - end if; - - -- Case of entity is in same unit as call or instantiation - - elsif not Inter_Unit_Only then - Check_Internal_Call (N, Ent, Outer_Scope, E); - end if; - end Check_A_Call; - - ----------------------------- - -- Check_Bad_Instantiation -- - ----------------------------- - - procedure Check_Bad_Instantiation (N : Node_Id) is - Ent : Entity_Id; - - begin - -- Nothing to do if we do not have an instantiation (happens in some - -- error cases, and also in the formal package declaration case) - - if Nkind (N) not in N_Generic_Instantiation then - return; - - -- Nothing to do if serious errors detected (avoid cascaded errors) - - elsif Serious_Errors_Detected /= 0 then - return; - - -- Nothing to do if not in full analysis mode - - elsif not Full_Analysis then - return; - - -- Nothing to do if inside a generic template - - elsif Inside_A_Generic then - return; - - -- Nothing to do if a library level instantiation - - elsif Nkind (Parent (N)) = N_Compilation_Unit then - return; - - -- Nothing to do if we are compiling a proper body for semantic - -- purposes only. The generic body may be in another proper body. - - elsif - Nkind (Parent (Unit_Declaration_Node (Main_Unit_Entity))) = N_Subunit - then - return; - end if; - - Ent := Get_Generic_Entity (N); - - -- The case we are interested in is when the generic spec is in the - -- current declarative part - - if not Same_Elaboration_Scope (Current_Scope, Scope (Ent)) - or else not In_Same_Extended_Unit (N, Ent) - then - return; - end if; - - -- If the generic entity is within a deeper instance than we are, then - -- either the instantiation to which we refer itself caused an ABE, in - -- which case that will be handled separately. Otherwise, we know that - -- the body we need appears as needed at the point of the instantiation. - -- If they are both at the same level but not within the same instance - -- then the body of the generic will be in the earlier instance. - - declare - D1 : constant Int := Instantiation_Depth (Sloc (Ent)); - D2 : constant Int := Instantiation_Depth (Sloc (N)); - - begin - if D1 > D2 then - return; - - elsif D1 = D2 - and then Is_Generic_Instance (Scope (Ent)) - and then not In_Open_Scopes (Scope (Ent)) - then - return; - end if; - end; - - -- Now we can proceed, if the entity being called has a completion, - -- then we are definitely OK, since we have already seen the body. - - if Has_Completion (Ent) then - return; - end if; - - -- If there is no body, then nothing to do - - if not Has_Generic_Body (N) then - return; - end if; - - -- Here we definitely have a bad instantiation - - Error_Msg_NE - ("?cannot instantiate& before body seen", N, Ent); - - if Present (Instance_Spec (N)) then - Supply_Bodies (Instance_Spec (N)); - end if; - - Error_Msg_N - ("\?Program_Error will be raised at run time", N); - Insert_Elab_Check (N); - Set_ABE_Is_Certain (N); - end Check_Bad_Instantiation; - - --------------------- - -- Check_Elab_Call -- - --------------------- - - procedure Check_Elab_Call - (N : Node_Id; - Outer_Scope : Entity_Id := Empty) - is - Ent : Entity_Id; - P : Node_Id; - - function Get_Called_Ent return Entity_Id; - -- Retrieve called entity. If this is a call to a protected subprogram, - -- entity is a selected component. The callable entity may be absent, - -- in which case there is no check to perform. This happens with - -- non-analyzed calls in nested generics. - - -------------------- - -- Get_Called_Ent -- - -------------------- - - function Get_Called_Ent return Entity_Id is - Nam : Node_Id; - - begin - Nam := Name (N); - - if No (Nam) then - return Empty; - - elsif Nkind (Nam) = N_Selected_Component then - return Entity (Selector_Name (Nam)); - - elsif not Is_Entity_Name (Nam) then - return Empty; - - else - return Entity (Nam); - end if; - end Get_Called_Ent; - - -- Start of processing for Check_Elab_Call - - begin - -- If the call does not come from the main unit, there is nothing to - -- check. Elaboration call from units in the context of the main unit - -- will lead to semantic dependencies when those units are compiled. - - if not In_Extended_Main_Code_Unit (N) then - return; - end if; - - -- For an entry call, check relevant restriction - - if Nkind (N) = N_Entry_Call_Statement - and then not In_Subprogram_Or_Concurrent_Unit - then - Check_Restriction (No_Entry_Calls_In_Elaboration_Code, N); - - -- Nothing to do if this is not a call (happens in some error - -- conditions, and in some cases where rewriting occurs). - - elsif Nkind (N) /= N_Function_Call - and then Nkind (N) /= N_Procedure_Call_Statement - then - return; - - -- Nothing to do if this is a call already rewritten for elab checking - - elsif Nkind (Parent (N)) = N_Conditional_Expression then - return; - - -- Nothing to do if inside a generic template - - elsif Inside_A_Generic - and then No (Enclosing_Generic_Body (N)) - then - return; - end if; - - -- Here we have a call at elaboration time which must be checked - - if Debug_Flag_LL then - Write_Str (" Check_Elab_Call: "); - - if No (Name (N)) - or else not Is_Entity_Name (Name (N)) - then - Write_Str ("<<not entity name>> "); - else - Write_Name (Chars (Entity (Name (N)))); - end if; - - Write_Str (" call at "); - Write_Location (Sloc (N)); - Write_Eol; - end if; - - -- Climb up the tree to make sure we are not inside default expression - -- of a parameter specification or a record component, since in both - -- these cases, we will be doing the actual call later, not now, and it - -- is at the time of the actual call (statically speaking) that we must - -- do our static check, not at the time of its initial analysis). - - -- However, we have to check calls within component definitions (e.g. - -- a function call that determines an array component bound), so we - -- terminate the loop in that case. - - P := Parent (N); - while Present (P) loop - if Nkind (P) = N_Parameter_Specification - or else - Nkind (P) = N_Component_Declaration - then - return; - - -- The call occurs within the constraint of a component, - -- so it must be checked. - - elsif Nkind (P) = N_Component_Definition then - exit; - - else - P := Parent (P); - end if; - end loop; - - -- Stuff that happens only at the outer level - - if No (Outer_Scope) then - Elab_Visited.Set_Last (0); - - -- Nothing to do if current scope is Standard (this is a bit odd, but - -- it happens in the case of generic instantiations). - - C_Scope := Current_Scope; - - if C_Scope = Standard_Standard then - return; - end if; - - -- First case, we are in elaboration code - - From_Elab_Code := not In_Subprogram_Or_Concurrent_Unit; - if From_Elab_Code then - - -- Complain if call that comes from source in preelaborated unit - -- and we are not inside a subprogram (i.e. we are in elab code). - - if Comes_From_Source (N) - and then In_Preelaborated_Unit - and then not In_Inlined_Body - then - -- This is a warning in GNAT mode allowing such calls to be - -- used in the predefined library with appropriate care. - - Error_Msg_Warn := GNAT_Mode; - Error_Msg_N - ("<non-static call not allowed in preelaborated unit", N); - return; - end if; - - -- Second case, we are inside a subprogram or concurrent unit, which - -- means we are not in elaboration code. - - else - -- In this case, the issue is whether we are inside the - -- declarative part of the unit in which we live, or inside its - -- statements. In the latter case, there is no issue of ABE calls - -- at this level (a call from outside to the unit in which we live - -- might cause an ABE, but that will be detected when we analyze - -- that outer level call, as it recurses into the called unit). - - -- Climb up the tree, doing this test, and also testing for being - -- inside a default expression, which, as discussed above, is not - -- checked at this stage. - - declare - P : Node_Id; - L : List_Id; - - begin - P := N; - loop - -- If we find a parentless subtree, it seems safe to assume - -- that we are not in a declarative part and that no - -- checking is required. - - if No (P) then - return; - end if; - - if Is_List_Member (P) then - L := List_Containing (P); - P := Parent (L); - else - L := No_List; - P := Parent (P); - end if; - - exit when Nkind (P) = N_Subunit; - - -- Filter out case of default expressions, where we do not - -- do the check at this stage. - - if Nkind (P) = N_Parameter_Specification - or else - Nkind (P) = N_Component_Declaration - then - return; - end if; - - -- A protected body has no elaboration code and contains - -- only other bodies. - - if Nkind (P) = N_Protected_Body then - return; - - elsif Nkind (P) = N_Subprogram_Body - or else - Nkind (P) = N_Task_Body - or else - Nkind (P) = N_Block_Statement - or else - Nkind (P) = N_Entry_Body - then - if L = Declarations (P) then - exit; - - -- We are not in elaboration code, but we are doing - -- dynamic elaboration checks, in this case, we still - -- need to do the call, since the subprogram we are in - -- could be called from another unit, also in dynamic - -- elaboration check mode, at elaboration time. - - elsif Dynamic_Elaboration_Checks then - - -- This is a rather new check, going into version - -- 3.14a1 for the first time (V1.80 of this unit), so - -- we provide a debug flag to enable it. That way we - -- have an easy work around for regressions that are - -- caused by this new check. This debug flag can be - -- removed later. - - if Debug_Flag_DD then - return; - end if; - - -- Do the check in this case - - exit; - - elsif Nkind (P) = N_Task_Body then - - -- The check is deferred until Check_Task_Activation - -- but we need to capture local suppress pragmas - -- that may inhibit checks on this call. - - Ent := Get_Called_Ent; - - if No (Ent) then - return; - - elsif Elaboration_Checks_Suppressed (Current_Scope) - or else Elaboration_Checks_Suppressed (Ent) - or else Elaboration_Checks_Suppressed (Scope (Ent)) - then - Set_No_Elaboration_Check (N); - end if; - - return; - - -- Static model, call is not in elaboration code, we - -- never need to worry, because in the static model the - -- top level caller always takes care of things. - - else - return; - end if; - end if; - end loop; - end; - end if; - end if; - - Ent := Get_Called_Ent; - - if No (Ent) then - return; - end if; - - -- Nothing to do if this is a recursive call (i.e. a call to - -- an entity that is already in the Elab_Call stack) - - for J in 1 .. Elab_Visited.Last loop - if Ent = Elab_Visited.Table (J) then - return; - end if; - end loop; - - -- See if we need to analyze this call. We analyze it if either of - -- the following conditions is met: - - -- It is an inner level call (since in this case it was triggered - -- by an outer level call from elaboration code), but only if the - -- call is within the scope of the original outer level call. - - -- It is an outer level call from elaboration code, or the called - -- entity is in the same elaboration scope. - - -- And in these cases, we will check both inter-unit calls and - -- intra-unit (within a single unit) calls. - - C_Scope := Current_Scope; - - -- If not outer level call, then we follow it if it is within - -- the original scope of the outer call. - - if Present (Outer_Scope) - and then Within (Scope (Ent), Outer_Scope) - then - Set_C_Scope; - Check_A_Call (N, Ent, Outer_Scope, Inter_Unit_Only => False); - - elsif Elaboration_Checks_Suppressed (Current_Scope) then - null; - - elsif From_Elab_Code then - Set_C_Scope; - Check_A_Call (N, Ent, Standard_Standard, Inter_Unit_Only => False); - - elsif Same_Elaboration_Scope (C_Scope, Scope (Ent)) then - Set_C_Scope; - Check_A_Call (N, Ent, Scope (Ent), Inter_Unit_Only => False); - - -- If none of those cases holds, but Dynamic_Elaboration_Checks mode - -- is set, then we will do the check, but only in the inter-unit case - -- (this is to accommodate unguarded elaboration calls from other units - -- in which this same mode is set). We don't want warnings in this case, - -- it would generate warnings having nothing to do with elaboration. - - elsif Dynamic_Elaboration_Checks then - Set_C_Scope; - Check_A_Call - (N, - Ent, - Standard_Standard, - Inter_Unit_Only => True, - Generate_Warnings => False); - - -- Otherwise nothing to do - - else - return; - end if; - - -- A call to an Init_Proc in elaboration code may bring additional - -- dependencies, if some of the record components thereof have - -- initializations that are function calls that come from source. We - -- treat the current node as a call to each of these functions, to check - -- their elaboration impact. - - if Is_Init_Proc (Ent) - and then From_Elab_Code - then - Process_Init_Proc : declare - Unit_Decl : constant Node_Id := Unit_Declaration_Node (Ent); - - function Find_Init_Call (Nod : Node_Id) return Traverse_Result; - -- Find subprogram calls within body of Init_Proc for Traverse - -- instantiation below. - - procedure Traverse_Body is new Traverse_Proc (Find_Init_Call); - -- Traversal procedure to find all calls with body of Init_Proc - - -------------------- - -- Find_Init_Call -- - -------------------- - - function Find_Init_Call (Nod : Node_Id) return Traverse_Result is - Func : Entity_Id; - - begin - if (Nkind (Nod) = N_Function_Call - or else Nkind (Nod) = N_Procedure_Call_Statement) - and then Is_Entity_Name (Name (Nod)) - then - Func := Entity (Name (Nod)); - - if Comes_From_Source (Func) then - Check_A_Call - (N, Func, Standard_Standard, Inter_Unit_Only => True); - end if; - - return OK; - - else - return OK; - end if; - end Find_Init_Call; - - -- Start of processing for Process_Init_Proc - - begin - if Nkind (Unit_Decl) = N_Subprogram_Body then - Traverse_Body (Handled_Statement_Sequence (Unit_Decl)); - end if; - end Process_Init_Proc; - end if; - end Check_Elab_Call; - - ----------------------- - -- Check_Elab_Assign -- - ----------------------- - - procedure Check_Elab_Assign (N : Node_Id) is - Ent : Entity_Id; - Scop : Entity_Id; - - Pkg_Spec : Entity_Id; - Pkg_Body : Entity_Id; - - begin - -- For record or array component, check prefix. If it is an access type, - -- then there is nothing to do (we do not know what is being assigned), - -- but otherwise this is an assignment to the prefix. - - if Nkind (N) = N_Indexed_Component - or else - Nkind (N) = N_Selected_Component - or else - Nkind (N) = N_Slice - then - if not Is_Access_Type (Etype (Prefix (N))) then - Check_Elab_Assign (Prefix (N)); - end if; - - return; - end if; - - -- For type conversion, check expression - - if Nkind (N) = N_Type_Conversion then - Check_Elab_Assign (Expression (N)); - return; - end if; - - -- Nothing to do if this is not an entity reference otherwise get entity - - if Is_Entity_Name (N) then - Ent := Entity (N); - else - return; - end if; - - -- What we are looking for is a reference in the body of a package that - -- modifies a variable declared in the visible part of the package spec. - - if Present (Ent) - and then Comes_From_Source (N) - and then not Suppress_Elaboration_Warnings (Ent) - and then Ekind (Ent) = E_Variable - and then not In_Private_Part (Ent) - and then Is_Library_Level_Entity (Ent) - then - Scop := Current_Scope; - loop - if No (Scop) or else Scop = Standard_Standard then - return; - elsif Ekind (Scop) = E_Package - and then Is_Compilation_Unit (Scop) - then - exit; - else - Scop := Scope (Scop); - end if; - end loop; - - -- Here Scop points to the containing library package - - Pkg_Spec := Scop; - Pkg_Body := Body_Entity (Pkg_Spec); - - -- All OK if the package has an Elaborate_Body pragma - - if Has_Pragma_Elaborate_Body (Scop) then - return; - end if; - - -- OK if entity being modified is not in containing package spec - - if not In_Same_Source_Unit (Scop, Ent) then - return; - end if; - - -- All OK if entity appears in generic package or generic instance. - -- We just get too messed up trying to give proper warnings in the - -- presence of generics. Better no message than a junk one. - - Scop := Scope (Ent); - while Present (Scop) and then Scop /= Pkg_Spec loop - if Ekind (Scop) = E_Generic_Package then - return; - elsif Ekind (Scop) = E_Package - and then Is_Generic_Instance (Scop) - then - return; - end if; - - Scop := Scope (Scop); - end loop; - - -- All OK if in task, don't issue warnings there - - if In_Task_Activation then - return; - end if; - - -- OK if no package body - - if No (Pkg_Body) then - return; - end if; - - -- OK if reference is not in package body - - if not In_Same_Source_Unit (Pkg_Body, N) then - return; - end if; - - -- OK if package body has no handled statement sequence - - declare - HSS : constant Node_Id := - Handled_Statement_Sequence (Declaration_Node (Pkg_Body)); - begin - if No (HSS) or else not Comes_From_Source (HSS) then - return; - end if; - end; - - -- We definitely have a case of a modification of an entity in - -- the package spec from the elaboration code of the package body. - -- We may not give the warning (because there are some additional - -- checks to avoid too many false positives), but it would be a good - -- idea for the binder to try to keep the body elaboration close to - -- the spec elaboration. - - Set_Elaborate_Body_Desirable (Pkg_Spec); - - -- All OK in gnat mode (we know what we are doing) - - if GNAT_Mode then - return; - end if; - - -- All OK if all warnings suppressed - - if Warning_Mode = Suppress then - return; - end if; - - -- All OK if elaboration checks suppressed for entity - - if Checks_May_Be_Suppressed (Ent) - and then Is_Check_Suppressed (Ent, Elaboration_Check) - then - return; - end if; - - -- OK if the entity is initialized. Note that the No_Initialization - -- flag usually means that the initialization has been rewritten into - -- assignments, but that still counts for us. - - declare - Decl : constant Node_Id := Declaration_Node (Ent); - begin - if Nkind (Decl) = N_Object_Declaration - and then (Present (Expression (Decl)) - or else No_Initialization (Decl)) - then - return; - end if; - end; - - -- Here is where we give the warning - - -- All OK if warnings suppressed on the entity - - if not Has_Warnings_Off (Ent) then - Error_Msg_Sloc := Sloc (Ent); - - Error_Msg_NE - ("?elaboration code may access& before it is initialized", - N, Ent); - Error_Msg_NE - ("\?suggest adding pragma Elaborate_Body to spec of &", - N, Scop); - Error_Msg_N - ("\?or an explicit initialization could be added #", N); - end if; - - if not All_Errors_Mode then - Set_Suppress_Elaboration_Warnings (Ent); - end if; - end if; - end Check_Elab_Assign; - - ---------------------- - -- Check_Elab_Calls -- - ---------------------- - - procedure Check_Elab_Calls is - begin - -- If expansion is disabled, do not generate any checks. Also skip - -- checks if any subunits are missing because in either case we lack the - -- full information that we need, and no object file will be created in - -- any case. - - if not Expander_Active - or else Is_Generic_Unit (Cunit_Entity (Main_Unit)) - or else Subunits_Missing - then - return; - end if; - - -- Skip delayed calls if we had any errors - - if Serious_Errors_Detected = 0 then - Delaying_Elab_Checks := False; - Expander_Mode_Save_And_Set (True); - - for J in Delay_Check.First .. Delay_Check.Last loop - Push_Scope (Delay_Check.Table (J).Curscop); - From_Elab_Code := Delay_Check.Table (J).From_Elab_Code; - - Check_Internal_Call_Continue ( - N => Delay_Check.Table (J).N, - E => Delay_Check.Table (J).E, - Outer_Scope => Delay_Check.Table (J).Outer_Scope, - Orig_Ent => Delay_Check.Table (J).Orig_Ent); - - Pop_Scope; - end loop; - - -- Set Delaying_Elab_Checks back on for next main compilation - - Expander_Mode_Restore; - Delaying_Elab_Checks := True; - end if; - end Check_Elab_Calls; - - ------------------------------ - -- Check_Elab_Instantiation -- - ------------------------------ - - procedure Check_Elab_Instantiation - (N : Node_Id; - Outer_Scope : Entity_Id := Empty) - is - Ent : Entity_Id; - - begin - -- Check for and deal with bad instantiation case. There is some - -- duplicated code here, but we will worry about this later ??? - - Check_Bad_Instantiation (N); - - if ABE_Is_Certain (N) then - return; - end if; - - -- Nothing to do if we do not have an instantiation (happens in some - -- error cases, and also in the formal package declaration case) - - if Nkind (N) not in N_Generic_Instantiation then - return; - end if; - - -- Nothing to do if inside a generic template - - if Inside_A_Generic then - return; - end if; - - -- Nothing to do if the instantiation is not in the main unit - - if not In_Extended_Main_Code_Unit (N) then - return; - end if; - - Ent := Get_Generic_Entity (N); - From_Elab_Code := not In_Subprogram_Or_Concurrent_Unit; - - -- See if we need to analyze this instantiation. We analyze it if - -- either of the following conditions is met: - - -- It is an inner level instantiation (since in this case it was - -- triggered by an outer level call from elaboration code), but - -- only if the instantiation is within the scope of the original - -- outer level call. - - -- It is an outer level instantiation from elaboration code, or the - -- instantiated entity is in the same elaboration scope. - - -- And in these cases, we will check both the inter-unit case and - -- the intra-unit (within a single unit) case. - - C_Scope := Current_Scope; - - if Present (Outer_Scope) - and then Within (Scope (Ent), Outer_Scope) - then - Set_C_Scope; - Check_A_Call (N, Ent, Outer_Scope, Inter_Unit_Only => False); - - elsif From_Elab_Code then - Set_C_Scope; - Check_A_Call (N, Ent, Standard_Standard, Inter_Unit_Only => False); - - elsif Same_Elaboration_Scope (C_Scope, Scope (Ent)) then - Set_C_Scope; - Check_A_Call (N, Ent, Scope (Ent), Inter_Unit_Only => False); - - -- If none of those cases holds, but Dynamic_Elaboration_Checks mode is - -- set, then we will do the check, but only in the inter-unit case (this - -- is to accommodate unguarded elaboration calls from other units in - -- which this same mode is set). We inhibit warnings in this case, since - -- this instantiation is not occurring in elaboration code. - - elsif Dynamic_Elaboration_Checks then - Set_C_Scope; - Check_A_Call - (N, - Ent, - Standard_Standard, - Inter_Unit_Only => True, - Generate_Warnings => False); - - else - return; - end if; - end Check_Elab_Instantiation; - - ------------------------- - -- Check_Internal_Call -- - ------------------------- - - procedure Check_Internal_Call - (N : Node_Id; - E : Entity_Id; - Outer_Scope : Entity_Id; - Orig_Ent : Entity_Id) - is - Inst_Case : constant Boolean := Nkind (N) in N_Generic_Instantiation; - - begin - -- If not function or procedure call or instantiation, then ignore - -- call (this happens in some error case and rewriting cases) - - if Nkind (N) /= N_Function_Call - and then - Nkind (N) /= N_Procedure_Call_Statement - and then - not Inst_Case - then - return; - - -- Nothing to do if this is a call or instantiation that has - -- already been found to be a sure ABE - - elsif ABE_Is_Certain (N) then - return; - - -- Nothing to do if errors already detected (avoid cascaded errors) - - elsif Serious_Errors_Detected /= 0 then - return; - - -- Nothing to do if not in full analysis mode - - elsif not Full_Analysis then - return; - - -- Nothing to do if analyzing in special spec-expression mode, since the - -- call is not actually being made at this time. - - elsif In_Spec_Expression then - return; - - -- Nothing to do for call to intrinsic subprogram - - elsif Is_Intrinsic_Subprogram (E) then - return; - - -- No need to trace local calls if checking task activation, because - -- other local bodies are elaborated already. - - elsif In_Task_Activation then - return; - end if; - - -- Delay this call if we are still delaying calls - - if Delaying_Elab_Checks then - Delay_Check.Append ( - (N => N, - E => E, - Orig_Ent => Orig_Ent, - Curscop => Current_Scope, - Outer_Scope => Outer_Scope, - From_Elab_Code => From_Elab_Code)); - return; - - -- Otherwise, call phase 2 continuation right now - - else - Check_Internal_Call_Continue (N, E, Outer_Scope, Orig_Ent); - end if; - end Check_Internal_Call; - - ---------------------------------- - -- Check_Internal_Call_Continue -- - ---------------------------------- - - procedure Check_Internal_Call_Continue - (N : Node_Id; - E : Entity_Id; - Outer_Scope : Entity_Id; - Orig_Ent : Entity_Id) - is - Loc : constant Source_Ptr := Sloc (N); - Inst_Case : constant Boolean := Is_Generic_Unit (E); - - Sbody : Node_Id; - Ebody : Entity_Id; - - function Find_Elab_Reference (N : Node_Id) return Traverse_Result; - -- Function applied to each node as we traverse the body. Checks for - -- call or entity reference that needs checking, and if so checks it. - -- Always returns OK, so entire tree is traversed, except that as - -- described below subprogram bodies are skipped for now. - - procedure Traverse is new Atree.Traverse_Proc (Find_Elab_Reference); - -- Traverse procedure using above Find_Elab_Reference function - - ------------------------- - -- Find_Elab_Reference -- - ------------------------- - - function Find_Elab_Reference (N : Node_Id) return Traverse_Result is - Actual : Node_Id; - - begin - -- If user has specified that there are no entry calls in elaboration - -- code, do not trace past an accept statement, because the rendez- - -- vous will happen after elaboration. - - if (Nkind (Original_Node (N)) = N_Accept_Statement - or else Nkind (Original_Node (N)) = N_Selective_Accept) - and then Restriction_Active (No_Entry_Calls_In_Elaboration_Code) - then - return Abandon; - - -- If we have a function call, check it - - elsif Nkind (N) = N_Function_Call then - Check_Elab_Call (N, Outer_Scope); - return OK; - - -- If we have a procedure call, check the call, and also check - -- arguments that are assignments (OUT or IN OUT mode formals). - - elsif Nkind (N) = N_Procedure_Call_Statement then - Check_Elab_Call (N, Outer_Scope); - - Actual := First_Actual (N); - while Present (Actual) loop - if Known_To_Be_Assigned (Actual) then - Check_Elab_Assign (Actual); - end if; - - Next_Actual (Actual); - end loop; - - return OK; - - -- If we have a generic instantiation, check it - - elsif Nkind (N) in N_Generic_Instantiation then - Check_Elab_Instantiation (N, Outer_Scope); - return OK; - - -- Skip subprogram bodies that come from source (wait for call to - -- analyze these). The reason for the come from source test is to - -- avoid catching task bodies. - - -- For task bodies, we should really avoid these too, waiting for the - -- task activation, but that's too much trouble to catch for now, so - -- we go in unconditionally. This is not so terrible, it means the - -- error backtrace is not quite complete, and we are too eager to - -- scan bodies of tasks that are unused, but this is hardly very - -- significant! - - elsif Nkind (N) = N_Subprogram_Body - and then Comes_From_Source (N) - then - return Skip; - - elsif Nkind (N) = N_Assignment_Statement - and then Comes_From_Source (N) - then - Check_Elab_Assign (Name (N)); - return OK; - - else - return OK; - end if; - end Find_Elab_Reference; - - -- Start of processing for Check_Internal_Call_Continue - - begin - -- Save outer level call if at outer level - - if Elab_Call.Last = 0 then - Outer_Level_Sloc := Loc; - end if; - - Elab_Visited.Append (E); - - -- If the call is to a function that renames a literal, no check - -- is needed. - - if Ekind (E) = E_Enumeration_Literal then - return; - end if; - - Sbody := Unit_Declaration_Node (E); - - if Nkind (Sbody) /= N_Subprogram_Body - and then - Nkind (Sbody) /= N_Package_Body - then - Ebody := Corresponding_Body (Sbody); - - if No (Ebody) then - return; - else - Sbody := Unit_Declaration_Node (Ebody); - end if; - end if; - - -- If the body appears after the outer level call or instantiation then - -- we have an error case handled below. - - if Earlier_In_Extended_Unit (Outer_Level_Sloc, Sloc (Sbody)) - and then not In_Task_Activation - then - null; - - -- If we have the instantiation case we are done, since we now - -- know that the body of the generic appeared earlier. - - elsif Inst_Case then - return; - - -- Otherwise we have a call, so we trace through the called body to see - -- if it has any problems. - - else - pragma Assert (Nkind (Sbody) = N_Subprogram_Body); - - Elab_Call.Append ((Cloc => Loc, Ent => E)); - - if Debug_Flag_LL then - Write_Str ("Elab_Call.Last = "); - Write_Int (Int (Elab_Call.Last)); - Write_Str (" Ent = "); - Write_Name (Chars (E)); - Write_Str (" at "); - Write_Location (Sloc (N)); - Write_Eol; - end if; - - -- Now traverse declarations and statements of subprogram body. Note - -- that we cannot simply Traverse (Sbody), since traverse does not - -- normally visit subprogram bodies. - - declare - Decl : Node_Id; - begin - Decl := First (Declarations (Sbody)); - while Present (Decl) loop - Traverse (Decl); - Next (Decl); - end loop; - end; - - Traverse (Handled_Statement_Sequence (Sbody)); - - Elab_Call.Decrement_Last; - return; - end if; - - -- Here is the case of calling a subprogram where the body has not yet - -- been encountered, a warning message is needed. - - -- If we have nothing in the call stack, then this is at the outer - -- level, and the ABE is bound to occur. - - if Elab_Call.Last = 0 then - if Inst_Case then - Error_Msg_NE - ("?cannot instantiate& before body seen", N, Orig_Ent); - else - Error_Msg_NE - ("?cannot call& before body seen", N, Orig_Ent); - end if; - - Error_Msg_N - ("\?Program_Error will be raised at run time", N); - Insert_Elab_Check (N); - - -- Call is not at outer level - - else - -- Deal with dynamic elaboration check - - if not Elaboration_Checks_Suppressed (E) then - Set_Elaboration_Entity_Required (E); - - -- Case of no elaboration entity allocated yet - - if No (Elaboration_Entity (E)) then - - -- Create object declaration for elaboration entity, and put it - -- just in front of the spec of the subprogram or generic unit, - -- in the same scope as this unit. - - declare - Loce : constant Source_Ptr := Sloc (E); - Ent : constant Entity_Id := - Make_Defining_Identifier (Loc, - Chars => New_External_Name (Chars (E), 'E')); - - begin - Set_Elaboration_Entity (E, Ent); - Push_Scope (Scope (E)); - - Insert_Action (Declaration_Node (E), - Make_Object_Declaration (Loce, - Defining_Identifier => Ent, - Object_Definition => - New_Occurrence_Of (Standard_Boolean, Loce), - Expression => New_Occurrence_Of (Standard_False, Loce))); - - -- Set elaboration flag at the point of the body - - Set_Elaboration_Flag (Sbody, E); - - -- Kill current value indication. This is necessary because - -- the tests of this flag are inserted out of sequence and - -- must not pick up bogus indications of the wrong constant - -- value. Also, this is never a true constant, since one way - -- or another, it gets reset. - - Set_Current_Value (Ent, Empty); - Set_Last_Assignment (Ent, Empty); - Set_Is_True_Constant (Ent, False); - Pop_Scope; - end; - end if; - - -- Generate check of the elaboration Boolean - - Insert_Elab_Check (N, - New_Occurrence_Of (Elaboration_Entity (E), Loc)); - end if; - - -- Generate the warning - - if not Suppress_Elaboration_Warnings (E) - and then not Elaboration_Checks_Suppressed (E) - then - if Inst_Case then - Error_Msg_NE - ("instantiation of& may occur before body is seen?", - N, Orig_Ent); - else - Error_Msg_NE - ("call to& may occur before body is seen?", N, Orig_Ent); - end if; - - Error_Msg_N - ("\Program_Error may be raised at run time?", N); - - Output_Calls (N); - end if; - end if; - - -- Set flag to suppress further warnings on same subprogram - -- unless in all errors mode - - if not All_Errors_Mode then - Set_Suppress_Elaboration_Warnings (E); - end if; - end Check_Internal_Call_Continue; - - --------------------------- - -- Check_Task_Activation -- - --------------------------- - - procedure Check_Task_Activation (N : Node_Id) is - Loc : constant Source_Ptr := Sloc (N); - Inter_Procs : constant Elist_Id := New_Elmt_List; - Intra_Procs : constant Elist_Id := New_Elmt_List; - Ent : Entity_Id; - P : Entity_Id; - Task_Scope : Entity_Id; - Cunit_SC : Boolean := False; - Decl : Node_Id; - Elmt : Elmt_Id; - Enclosing : Entity_Id; - - procedure Add_Task_Proc (Typ : Entity_Id); - -- Add to Task_Procs the task body procedure(s) of task types in Typ. - -- For record types, this procedure recurses over component types. - - procedure Collect_Tasks (Decls : List_Id); - -- Collect the types of the tasks that are to be activated in the given - -- list of declarations, in order to perform elaboration checks on the - -- corresponding task procedures which are called implicitly here. - - function Outer_Unit (E : Entity_Id) return Entity_Id; - -- find enclosing compilation unit of Entity, ignoring subunits, or - -- else enclosing subprogram. If E is not a package, there is no need - -- for inter-unit elaboration checks. - - ------------------- - -- Add_Task_Proc -- - ------------------- - - procedure Add_Task_Proc (Typ : Entity_Id) is - Comp : Entity_Id; - Proc : Entity_Id := Empty; - - begin - if Is_Task_Type (Typ) then - Proc := Get_Task_Body_Procedure (Typ); - - elsif Is_Array_Type (Typ) - and then Has_Task (Base_Type (Typ)) - then - Add_Task_Proc (Component_Type (Typ)); - - elsif Is_Record_Type (Typ) - and then Has_Task (Base_Type (Typ)) - then - Comp := First_Component (Typ); - while Present (Comp) loop - Add_Task_Proc (Etype (Comp)); - Comp := Next_Component (Comp); - end loop; - end if; - - -- If the task type is another unit, we will perform the usual - -- elaboration check on its enclosing unit. If the type is in the - -- same unit, we can trace the task body as for an internal call, - -- but we only need to examine other external calls, because at - -- the point the task is activated, internal subprogram bodies - -- will have been elaborated already. We keep separate lists for - -- each kind of task. - - -- Skip this test if errors have occurred, since in this case - -- we can get false indications. - - if Serious_Errors_Detected /= 0 then - return; - end if; - - if Present (Proc) then - if Outer_Unit (Scope (Proc)) = Enclosing then - - if No (Corresponding_Body (Unit_Declaration_Node (Proc))) - and then - (not Is_Generic_Instance (Scope (Proc)) - or else - Scope (Proc) = Scope (Defining_Identifier (Decl))) - then - Error_Msg_N - ("task will be activated before elaboration of its body?", - Decl); - Error_Msg_N - ("\Program_Error will be raised at run-time?", Decl); - - elsif - Present (Corresponding_Body (Unit_Declaration_Node (Proc))) - then - Append_Elmt (Proc, Intra_Procs); - end if; - - else - -- No need for multiple entries of the same type - - Elmt := First_Elmt (Inter_Procs); - while Present (Elmt) loop - if Node (Elmt) = Proc then - return; - end if; - - Next_Elmt (Elmt); - end loop; - - Append_Elmt (Proc, Inter_Procs); - end if; - end if; - end Add_Task_Proc; - - ------------------- - -- Collect_Tasks -- - ------------------- - - procedure Collect_Tasks (Decls : List_Id) is - begin - if Present (Decls) then - Decl := First (Decls); - while Present (Decl) loop - if Nkind (Decl) = N_Object_Declaration - and then Has_Task (Etype (Defining_Identifier (Decl))) - then - Add_Task_Proc (Etype (Defining_Identifier (Decl))); - end if; - - Next (Decl); - end loop; - end if; - end Collect_Tasks; - - ---------------- - -- Outer_Unit -- - ---------------- - - function Outer_Unit (E : Entity_Id) return Entity_Id is - Outer : Entity_Id; - - begin - Outer := E; - while Present (Outer) loop - if Elaboration_Checks_Suppressed (Outer) then - Cunit_SC := True; - end if; - - exit when Is_Child_Unit (Outer) - or else Scope (Outer) = Standard_Standard - or else Ekind (Outer) /= E_Package; - Outer := Scope (Outer); - end loop; - - return Outer; - end Outer_Unit; - - -- Start of processing for Check_Task_Activation - - begin - Enclosing := Outer_Unit (Current_Scope); - - -- Find all tasks declared in the current unit - - if Nkind (N) = N_Package_Body then - P := Unit_Declaration_Node (Corresponding_Spec (N)); - - Collect_Tasks (Declarations (N)); - Collect_Tasks (Visible_Declarations (Specification (P))); - Collect_Tasks (Private_Declarations (Specification (P))); - - elsif Nkind (N) = N_Package_Declaration then - Collect_Tasks (Visible_Declarations (Specification (N))); - Collect_Tasks (Private_Declarations (Specification (N))); - - else - Collect_Tasks (Declarations (N)); - end if; - - -- We only perform detailed checks in all tasks are library level - -- entities. If the master is a subprogram or task, activation will - -- depend on the activation of the master itself. - - -- Should dynamic checks be added in the more general case??? - - if Ekind (Enclosing) /= E_Package then - return; - end if; - - -- For task types defined in other units, we want the unit containing - -- the task body to be elaborated before the current one. - - Elmt := First_Elmt (Inter_Procs); - while Present (Elmt) loop - Ent := Node (Elmt); - Task_Scope := Outer_Unit (Scope (Ent)); - - if not Is_Compilation_Unit (Task_Scope) then - null; - - elsif Suppress_Elaboration_Warnings (Task_Scope) - or else Elaboration_Checks_Suppressed (Task_Scope) - then - null; - - elsif Dynamic_Elaboration_Checks then - if not Elaboration_Checks_Suppressed (Ent) - and then not Cunit_SC - and then - not Restriction_Active (No_Entry_Calls_In_Elaboration_Code) - then - -- Runtime elaboration check required. Generate check of the - -- elaboration Boolean for the unit containing the entity. - - Insert_Elab_Check (N, - Make_Attribute_Reference (Loc, - Attribute_Name => Name_Elaborated, - Prefix => - New_Occurrence_Of - (Spec_Entity (Task_Scope), Loc))); - end if; - - else - -- Force the binder to elaborate other unit first - - if not Suppress_Elaboration_Warnings (Ent) - and then not Elaboration_Checks_Suppressed (Ent) - and then Elab_Warnings - and then not Suppress_Elaboration_Warnings (Task_Scope) - and then not Elaboration_Checks_Suppressed (Task_Scope) - then - Error_Msg_Node_2 := Task_Scope; - Error_Msg_NE ("activation of an instance of task type&" & - " requires pragma Elaborate_All on &?", N, Ent); - end if; - - Activate_Elaborate_All_Desirable (N, Task_Scope); - Set_Suppress_Elaboration_Warnings (Task_Scope); - end if; - - Next_Elmt (Elmt); - end loop; - - -- For tasks declared in the current unit, trace other calls within - -- the task procedure bodies, which are available. - - In_Task_Activation := True; - - Elmt := First_Elmt (Intra_Procs); - while Present (Elmt) loop - Ent := Node (Elmt); - Check_Internal_Call_Continue (N, Ent, Enclosing, Ent); - Next_Elmt (Elmt); - end loop; - - In_Task_Activation := False; - end Check_Task_Activation; - - -------------------------------- - -- Set_Elaboration_Constraint -- - -------------------------------- - - procedure Set_Elaboration_Constraint - (Call : Node_Id; - Subp : Entity_Id; - Scop : Entity_Id) - is - Elab_Unit : Entity_Id; - Init_Call : constant Boolean := - Chars (Subp) = Name_Initialize - and then Comes_From_Source (Subp) - and then Present (Parameter_Associations (Call)) - and then Is_Controlled (Etype (First_Actual (Call))); - begin - -- If the unit is mentioned in a with_clause of the current unit, it is - -- visible, and we can set the elaboration flag. - - if Is_Immediately_Visible (Scop) - or else (Is_Child_Unit (Scop) and then Is_Visible_Child_Unit (Scop)) - then - Activate_Elaborate_All_Desirable (Call, Scop); - Set_Suppress_Elaboration_Warnings (Scop, True); - return; - end if; - - -- If this is not an initialization call or a call using object notation - -- we know that the unit of the called entity is in the context, and - -- we can set the flag as well. The unit need not be visible if the call - -- occurs within an instantiation. - - if Is_Init_Proc (Subp) - or else Init_Call - or else Nkind (Original_Node (Call)) = N_Selected_Component - then - null; -- detailed processing follows. - - else - Activate_Elaborate_All_Desirable (Call, Scop); - Set_Suppress_Elaboration_Warnings (Scop, True); - return; - end if; - - -- If the unit is not in the context, there must be an intermediate unit - -- that is, on which we need to place to elaboration flag. This happens - -- with init proc calls. - - if Is_Init_Proc (Subp) - or else Init_Call - then - -- The initialization call is on an object whose type is not declared - -- in the same scope as the subprogram. The type of the object must - -- be a subtype of the type of operation. This object is the first - -- actual in the call. - - declare - Typ : constant Entity_Id := - Etype (First (Parameter_Associations (Call))); - begin - Elab_Unit := Scope (Typ); - while (Present (Elab_Unit)) - and then not Is_Compilation_Unit (Elab_Unit) - loop - Elab_Unit := Scope (Elab_Unit); - end loop; - end; - - -- If original node uses selected component notation, the prefix is - -- visible and determines the scope that must be elaborated. After - -- rewriting, the prefix is the first actual in the call. - - elsif Nkind (Original_Node (Call)) = N_Selected_Component then - Elab_Unit := Scope (Etype (First (Parameter_Associations (Call)))); - - -- Not one of special cases above - - else - -- Using previously computed scope. If the elaboration check is - -- done after analysis, the scope is not visible any longer, but - -- must still be in the context. - - Elab_Unit := Scop; - end if; - - Activate_Elaborate_All_Desirable (Call, Elab_Unit); - Set_Suppress_Elaboration_Warnings (Elab_Unit, True); - end Set_Elaboration_Constraint; - - ---------------------- - -- Has_Generic_Body -- - ---------------------- - - function Has_Generic_Body (N : Node_Id) return Boolean is - Ent : constant Entity_Id := Get_Generic_Entity (N); - Decl : constant Node_Id := Unit_Declaration_Node (Ent); - Scop : Entity_Id; - - function Find_Body_In (E : Entity_Id; N : Node_Id) return Node_Id; - -- Determine if the list of nodes headed by N and linked by Next - -- contains a package body for the package spec entity E, and if so - -- return the package body. If not, then returns Empty. - - function Load_Package_Body (Nam : Unit_Name_Type) return Node_Id; - -- This procedure is called load the unit whose name is given by Nam. - -- This unit is being loaded to see whether it contains an optional - -- generic body. The returned value is the loaded unit, which is always - -- a package body (only package bodies can contain other entities in the - -- sense in which Has_Generic_Body is interested). We only attempt to - -- load bodies if we are generating code. If we are in semantics check - -- only mode, then it would be wrong to load bodies that are not - -- required from a semantic point of view, so in this case we return - -- Empty. The result is that the caller may incorrectly decide that a - -- generic spec does not have a body when in fact it does, but the only - -- harm in this is that some warnings on elaboration problems may be - -- lost in semantic checks only mode, which is not big loss. We also - -- return Empty if we go for a body and it is not there. - - function Locate_Corresponding_Body (PE : Entity_Id) return Node_Id; - -- PE is the entity for a package spec. This function locates the - -- corresponding package body, returning Empty if none is found. The - -- package body returned is fully parsed but may not yet be analyzed, - -- so only syntactic fields should be referenced. - - ------------------ - -- Find_Body_In -- - ------------------ - - function Find_Body_In (E : Entity_Id; N : Node_Id) return Node_Id is - Nod : Node_Id; - - begin - Nod := N; - while Present (Nod) loop - - -- If we found the package body we are looking for, return it - - if Nkind (Nod) = N_Package_Body - and then Chars (Defining_Unit_Name (Nod)) = Chars (E) - then - return Nod; - - -- If we found the stub for the body, go after the subunit, - -- loading it if necessary. - - elsif Nkind (Nod) = N_Package_Body_Stub - and then Chars (Defining_Identifier (Nod)) = Chars (E) - then - if Present (Library_Unit (Nod)) then - return Unit (Library_Unit (Nod)); - - else - return Load_Package_Body (Get_Unit_Name (Nod)); - end if; - - -- If neither package body nor stub, keep looking on chain - - else - Next (Nod); - end if; - end loop; - - return Empty; - end Find_Body_In; - - ----------------------- - -- Load_Package_Body -- - ----------------------- - - function Load_Package_Body (Nam : Unit_Name_Type) return Node_Id is - U : Unit_Number_Type; - - begin - if Operating_Mode /= Generate_Code then - return Empty; - else - U := - Load_Unit - (Load_Name => Nam, - Required => False, - Subunit => False, - Error_Node => N); - - if U = No_Unit then - return Empty; - else - return Unit (Cunit (U)); - end if; - end if; - end Load_Package_Body; - - ------------------------------- - -- Locate_Corresponding_Body -- - ------------------------------- - - function Locate_Corresponding_Body (PE : Entity_Id) return Node_Id is - Spec : constant Node_Id := Declaration_Node (PE); - Decl : constant Node_Id := Parent (Spec); - Scop : constant Entity_Id := Scope (PE); - PBody : Node_Id; - - begin - if Is_Library_Level_Entity (PE) then - - -- If package is a library unit that requires a body, we have no - -- choice but to go after that body because it might contain an - -- optional body for the original generic package. - - if Unit_Requires_Body (PE) then - - -- Load the body. Note that we are a little careful here to use - -- Spec to get the unit number, rather than PE or Decl, since - -- in the case where the package is itself a library level - -- instantiation, Spec will properly reference the generic - -- template, which is what we really want. - - return - Load_Package_Body - (Get_Body_Name (Unit_Name (Get_Source_Unit (Spec)))); - - -- But if the package is a library unit that does NOT require - -- a body, then no body is permitted, so we are sure that there - -- is no body for the original generic package. - - else - return Empty; - end if; - - -- Otherwise look and see if we are embedded in a further package - - elsif Is_Package_Or_Generic_Package (Scop) then - - -- If so, get the body of the enclosing package, and look in - -- its package body for the package body we are looking for. - - PBody := Locate_Corresponding_Body (Scop); - - if No (PBody) then - return Empty; - else - return Find_Body_In (PE, First (Declarations (PBody))); - end if; - - -- If we are not embedded in a further package, then the body - -- must be in the same declarative part as we are. - - else - return Find_Body_In (PE, Next (Decl)); - end if; - end Locate_Corresponding_Body; - - -- Start of processing for Has_Generic_Body - - begin - if Present (Corresponding_Body (Decl)) then - return True; - - elsif Unit_Requires_Body (Ent) then - return True; - - -- Compilation units cannot have optional bodies - - elsif Is_Compilation_Unit (Ent) then - return False; - - -- Otherwise look at what scope we are in - - else - Scop := Scope (Ent); - - -- Case of entity is in other than a package spec, in this case - -- the body, if present, must be in the same declarative part. - - if not Is_Package_Or_Generic_Package (Scop) then - declare - P : Node_Id; - - begin - -- Declaration node may get us a spec, so if so, go to - -- the parent declaration. - - P := Declaration_Node (Ent); - while not Is_List_Member (P) loop - P := Parent (P); - end loop; - - return Present (Find_Body_In (Ent, Next (P))); - end; - - -- If the entity is in a package spec, then we have to locate - -- the corresponding package body, and look there. - - else - declare - PBody : constant Node_Id := Locate_Corresponding_Body (Scop); - - begin - if No (PBody) then - return False; - else - return - Present - (Find_Body_In (Ent, (First (Declarations (PBody))))); - end if; - end; - end if; - end if; - end Has_Generic_Body; - - ----------------------- - -- Insert_Elab_Check -- - ----------------------- - - procedure Insert_Elab_Check (N : Node_Id; C : Node_Id := Empty) is - Nod : Node_Id; - Loc : constant Source_Ptr := Sloc (N); - - begin - -- If expansion is disabled, do not generate any checks. Also - -- skip checks if any subunits are missing because in either - -- case we lack the full information that we need, and no object - -- file will be created in any case. - - if not Expander_Active or else Subunits_Missing then - return; - end if; - - -- If we have a generic instantiation, where Instance_Spec is set, - -- then this field points to a generic instance spec that has - -- been inserted before the instantiation node itself, so that - -- is where we want to insert a check. - - if Nkind (N) in N_Generic_Instantiation - and then Present (Instance_Spec (N)) - then - Nod := Instance_Spec (N); - else - Nod := N; - end if; - - -- If we are inserting at the top level, insert in Aux_Decls - - if Nkind (Parent (Nod)) = N_Compilation_Unit then - declare - ADN : constant Node_Id := Aux_Decls_Node (Parent (Nod)); - R : Node_Id; - - begin - if No (C) then - R := - Make_Raise_Program_Error (Loc, - Reason => PE_Access_Before_Elaboration); - else - R := - Make_Raise_Program_Error (Loc, - Condition => Make_Op_Not (Loc, C), - Reason => PE_Access_Before_Elaboration); - end if; - - if No (Declarations (ADN)) then - Set_Declarations (ADN, New_List (R)); - else - Append_To (Declarations (ADN), R); - end if; - - Analyze (R); - end; - - -- Otherwise just insert before the node in question. However, if - -- the context of the call has already been analyzed, an insertion - -- will not work if it depends on subsequent expansion (e.g. a call in - -- a branch of a short-circuit). In that case we replace the call with - -- a conditional expression, or with a Raise if it is unconditional. - -- Unfortunately this does not work if the call has a dynamic size, - -- because gigi regards it as a dynamic-sized temporary. If such a call - -- appears in a short-circuit expression, the elaboration check will be - -- missed (rare enough ???). Otherwise, the code below inserts the check - -- at the appropriate place before the call. Same applies in the even - -- rarer case the return type has a known size but is unconstrained. - - else - if Nkind (N) = N_Function_Call - and then Analyzed (Parent (N)) - and then Size_Known_At_Compile_Time (Etype (N)) - and then - (not Has_Discriminants (Etype (N)) - or else Is_Constrained (Etype (N))) - - then - declare - Typ : constant Entity_Id := Etype (N); - Chk : constant Boolean := Do_Range_Check (N); - - R : constant Node_Id := - Make_Raise_Program_Error (Loc, - Reason => PE_Access_Before_Elaboration); - - begin - Set_Etype (R, Typ); - - if No (C) then - Rewrite (N, R); - - else - Rewrite (N, - Make_Conditional_Expression (Loc, - Expressions => New_List (C, Relocate_Node (N), R))); - end if; - - Analyze_And_Resolve (N, Typ); - - -- If the original call requires a range check, so does the - -- conditional expression. - - if Chk then - Enable_Range_Check (N); - else - Set_Do_Range_Check (N, False); - end if; - end; - - else - if No (C) then - Insert_Action (Nod, - Make_Raise_Program_Error (Loc, - Reason => PE_Access_Before_Elaboration)); - else - Insert_Action (Nod, - Make_Raise_Program_Error (Loc, - Condition => - Make_Op_Not (Loc, - Right_Opnd => C), - Reason => PE_Access_Before_Elaboration)); - end if; - end if; - end if; - end Insert_Elab_Check; - - ------------------ - -- Output_Calls -- - ------------------ - - procedure Output_Calls (N : Node_Id) is - Ent : Entity_Id; - - function Is_Printable_Error_Name (Nm : Name_Id) return Boolean; - -- An internal function, used to determine if a name, Nm, is either - -- a non-internal name, or is an internal name that is printable - -- by the error message circuits (i.e. it has a single upper - -- case letter at the end). - - function Is_Printable_Error_Name (Nm : Name_Id) return Boolean is - begin - if not Is_Internal_Name (Nm) then - return True; - - elsif Name_Len = 1 then - return False; - - else - Name_Len := Name_Len - 1; - return not Is_Internal_Name; - end if; - end Is_Printable_Error_Name; - - -- Start of processing for Output_Calls - - begin - for J in reverse 1 .. Elab_Call.Last loop - Error_Msg_Sloc := Elab_Call.Table (J).Cloc; - - Ent := Elab_Call.Table (J).Ent; - - if Is_Generic_Unit (Ent) then - Error_Msg_NE ("\?& instantiated #", N, Ent); - - elsif Is_Init_Proc (Ent) then - Error_Msg_N ("\?initialization procedure called #", N); - - elsif Is_Printable_Error_Name (Chars (Ent)) then - Error_Msg_NE ("\?& called #", N, Ent); - - else - Error_Msg_N ("\? called #", N); - end if; - end loop; - end Output_Calls; - - ---------------------------- - -- Same_Elaboration_Scope -- - ---------------------------- - - function Same_Elaboration_Scope (Scop1, Scop2 : Entity_Id) return Boolean is - S1 : Entity_Id; - S2 : Entity_Id; - - begin - -- Find elaboration scope for Scop1 - -- This is either a subprogram or a compilation unit. - - S1 := Scop1; - while S1 /= Standard_Standard - and then not Is_Compilation_Unit (S1) - and then (Ekind (S1) = E_Package - or else - Ekind (S1) = E_Protected_Type - or else - Ekind (S1) = E_Block) - loop - S1 := Scope (S1); - end loop; - - -- Find elaboration scope for Scop2 - - S2 := Scop2; - while S2 /= Standard_Standard - and then not Is_Compilation_Unit (S2) - and then (Ekind (S2) = E_Package - or else - Ekind (S2) = E_Protected_Type - or else - Ekind (S2) = E_Block) - loop - S2 := Scope (S2); - end loop; - - return S1 = S2; - end Same_Elaboration_Scope; - - ----------------- - -- Set_C_Scope -- - ----------------- - - procedure Set_C_Scope is - begin - while not Is_Compilation_Unit (C_Scope) loop - C_Scope := Scope (C_Scope); - end loop; - end Set_C_Scope; - - ----------------- - -- Spec_Entity -- - ----------------- - - function Spec_Entity (E : Entity_Id) return Entity_Id is - Decl : Node_Id; - - begin - -- Check for case of body entity - -- Why is the check for E_Void needed??? - - if Ekind (E) = E_Void - or else Ekind (E) = E_Subprogram_Body - or else Ekind (E) = E_Package_Body - then - Decl := E; - - loop - Decl := Parent (Decl); - exit when Nkind (Decl) in N_Proper_Body; - end loop; - - return Corresponding_Spec (Decl); - - else - return E; - end if; - end Spec_Entity; - - ------------------- - -- Supply_Bodies -- - ------------------- - - procedure Supply_Bodies (N : Node_Id) is - begin - if Nkind (N) = N_Subprogram_Declaration then - declare - Ent : constant Entity_Id := Defining_Unit_Name (Specification (N)); - begin - - -- Internal subprograms will already have a generated body, so - -- there is no need to provide a stub for them. - - if No (Corresponding_Body (N)) then - declare - Loc : constant Source_Ptr := Sloc (N); - B : Node_Id; - Formals : constant List_Id := - Copy_Parameter_List (Ent); - Nam : constant Entity_Id := - Make_Defining_Identifier (Loc, Chars (Ent)); - Spec : Node_Id; - Stats : constant List_Id := - New_List - (Make_Raise_Program_Error (Loc, - Reason => PE_Access_Before_Elaboration)); - begin - if Ekind (Ent) = E_Function then - Spec := - Make_Function_Specification (Loc, - Defining_Unit_Name => Nam, - Parameter_Specifications => Formals, - Result_Definition => - New_Copy_Tree - (Result_Definition (Specification (N)))); - - -- We cannot reliably make a return statement for this - -- body, but none is needed because the call raises - -- program error. - - Set_Return_Present (Ent); - - else - Spec := - Make_Procedure_Specification (Loc, - Defining_Unit_Name => Nam, - Parameter_Specifications => Formals); - end if; - - B := Make_Subprogram_Body (Loc, - Specification => Spec, - Declarations => New_List, - Handled_Statement_Sequence => - Make_Handled_Sequence_Of_Statements (Loc, Stats)); - Insert_After (N, B); - Analyze (B); - end; - end if; - end; - - elsif Nkind (N) = N_Package_Declaration then - declare - Spec : constant Node_Id := Specification (N); - begin - Push_Scope (Defining_Unit_Name (Spec)); - Supply_Bodies (Visible_Declarations (Spec)); - Supply_Bodies (Private_Declarations (Spec)); - Pop_Scope; - end; - end if; - end Supply_Bodies; - - procedure Supply_Bodies (L : List_Id) is - Elmt : Node_Id; - begin - if Present (L) then - Elmt := First (L); - while Present (Elmt) loop - Supply_Bodies (Elmt); - Next (Elmt); - end loop; - end if; - end Supply_Bodies; - - ------------ - -- Within -- - ------------ - - function Within (E1, E2 : Entity_Id) return Boolean is - Scop : Entity_Id; - begin - Scop := E1; - loop - if Scop = E2 then - return True; - elsif Scop = Standard_Standard then - return False; - else - Scop := Scope (Scop); - end if; - end loop; - end Within; - - -------------------------- - -- Within_Elaborate_All -- - -------------------------- - - function Within_Elaborate_All (E : Entity_Id) return Boolean is - Item : Node_Id; - Item2 : Node_Id; - Elab_Id : Entity_Id; - Par : Node_Id; - - begin - Item := First (Context_Items (Cunit (Current_Sem_Unit))); - while Present (Item) loop - if Nkind (Item) = N_Pragma - and then Pragma_Name (Item) = Name_Elaborate_All - then - -- Return if some previous error on the pragma itself - - if Error_Posted (Item) then - return False; - end if; - - Elab_Id := - Entity - (Expression (First (Pragma_Argument_Associations (Item)))); - - Par := Parent (Unit_Declaration_Node (Elab_Id)); - - Item2 := First (Context_Items (Par)); - while Present (Item2) loop - if Nkind (Item2) = N_With_Clause - and then Entity (Name (Item2)) = E - then - return True; - end if; - - Next (Item2); - end loop; - end if; - - Next (Item); - end loop; - - return False; - end Within_Elaborate_All; - -end Sem_Elab; |