1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- S E M _ C H 6 -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 1992-2019, 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------------------------------------------------------------------------------ 25 26with Types; use Types; 27package Sem_Ch6 is 28 29 type Conformance_Type is 30 (Type_Conformant, Mode_Conformant, Subtype_Conformant, Fully_Conformant); 31 pragma Ordered (Conformance_Type); 32 -- Conformance type used in conformance checks between specs and bodies, 33 -- and for overriding. The literals match the RM definitions of the 34 -- corresponding terms. This is an ordered type, since each conformance 35 -- type is stronger than the ones preceding it. 36 37 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id); 38 procedure Analyze_Expression_Function (N : Node_Id); 39 procedure Analyze_Extended_Return_Statement (N : Node_Id); 40 procedure Analyze_Function_Call (N : Node_Id); 41 procedure Analyze_Operator_Symbol (N : Node_Id); 42 procedure Analyze_Parameter_Association (N : Node_Id); 43 procedure Analyze_Procedure_Call (N : Node_Id); 44 procedure Analyze_Simple_Return_Statement (N : Node_Id); 45 procedure Analyze_Subprogram_Declaration (N : Node_Id); 46 procedure Analyze_Subprogram_Body (N : Node_Id); 47 48 function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id; 49 -- Analyze subprogram specification in both subprogram declarations 50 -- and body declarations. Returns the defining entity for the 51 -- specification N. 52 53 procedure Check_Conventions (Typ : Entity_Id); 54 -- Ada 2005 (AI-430): Check that the conventions of all inherited and 55 -- overridden dispatching operations of type Typ are consistent with their 56 -- respective counterparts. 57 58 procedure Check_Delayed_Subprogram (Designator : Entity_Id); 59 -- Designator can be a E_Subprogram_Type, E_Procedure or E_Function. If a 60 -- type in its profile depends on a private type without a full 61 -- declaration, indicate that the subprogram or type is delayed. 62 63 procedure Check_Discriminant_Conformance 64 (N : Node_Id; 65 Prev : Entity_Id; 66 Prev_Loc : Node_Id); 67 -- Check that the discriminants of a full type N fully conform to the 68 -- discriminants of the corresponding partial view Prev. Prev_Loc indicates 69 -- the source location of the partial view, which may be different than 70 -- Prev in the case of private types. 71 72 procedure Check_Fully_Conformant 73 (New_Id : Entity_Id; 74 Old_Id : Entity_Id; 75 Err_Loc : Node_Id := Empty); 76 -- Check that two callable entities (subprograms, entries, literals) 77 -- are fully conformant, post error message if not (RM 6.3.1(17)) with 78 -- the flag being placed on the Err_Loc node if it is specified, and 79 -- on the appropriate component of the New_Id construct if not. Note: 80 -- when checking spec/body conformance, New_Id must be the body entity 81 -- and Old_Id is the spec entity (the code in the implementation relies 82 -- on this ordering, and in any case, this makes sense, since if flags 83 -- are to be placed on the construct, they clearly belong on the body. 84 85 procedure Check_Mode_Conformant 86 (New_Id : Entity_Id; 87 Old_Id : Entity_Id; 88 Err_Loc : Node_Id := Empty; 89 Get_Inst : Boolean := False); 90 -- Check that two callable entities (subprograms, entries, literals) 91 -- are mode conformant, post error message if not (RM 6.3.1(15)) with 92 -- the flag being placed on the Err_Loc node if it is specified, and 93 -- on the appropriate component of the New_Id construct if not. The 94 -- argument Get_Inst is set to True when this is a check against a 95 -- formal access-to-subprogram type, indicating that mapping of types 96 -- is needed. 97 98 procedure Check_Overriding_Indicator 99 (Subp : Entity_Id; 100 Overridden_Subp : Entity_Id; 101 Is_Primitive : Boolean); 102 -- Verify the consistency of an overriding_indicator given for subprogram 103 -- declaration, body, renaming, or instantiation. Overridden_Subp is set 104 -- if the scope where we are introducing the subprogram contains a 105 -- type-conformant subprogram that becomes hidden by the new subprogram. 106 -- Is_Primitive indicates whether the subprogram is primitive. 107 108 procedure Check_Subtype_Conformant 109 (New_Id : Entity_Id; 110 Old_Id : Entity_Id; 111 Err_Loc : Node_Id := Empty; 112 Skip_Controlling_Formals : Boolean := False; 113 Get_Inst : Boolean := False); 114 -- Check that two callable entities (subprograms, entries, literals) 115 -- are subtype conformant, post error message if not (RM 6.3.1(16)), 116 -- the flag being placed on the Err_Loc node if it is specified, and 117 -- on the appropriate component of the New_Id construct if not. 118 -- Skip_Controlling_Formals is True when checking the conformance of 119 -- a subprogram that implements an interface operation. In that case, 120 -- only the non-controlling formals can (and must) be examined. The 121 -- argument Get_Inst is set to True when this is a check against a 122 -- formal access-to-subprogram type, indicating that mapping of types 123 -- is needed. 124 125 procedure Check_Synchronized_Overriding 126 (Def_Id : Entity_Id; 127 Overridden_Subp : out Entity_Id); 128 -- First determine if Def_Id is an entry or a subprogram either defined in 129 -- the scope of a task or protected type, or that is a primitive of such 130 -- a type. Check whether Def_Id overrides a subprogram of an interface 131 -- implemented by the synchronized type, returning the overridden entity 132 -- or Empty. 133 134 procedure Check_Type_Conformant 135 (New_Id : Entity_Id; 136 Old_Id : Entity_Id; 137 Err_Loc : Node_Id := Empty); 138 -- Check that two callable entities (subprograms, entries, literals) 139 -- are type conformant, post error message if not (RM 6.3.1(14)) with 140 -- the flag being placed on the Err_Loc node if it is specified, and 141 -- on the appropriate component of the New_Id construct if not. 142 143 function Conforming_Types 144 (T1 : Entity_Id; 145 T2 : Entity_Id; 146 Ctype : Conformance_Type; 147 Get_Inst : Boolean := False) return Boolean; 148 -- Check that the types of two formal parameters are conforming. In most 149 -- cases this is just a name comparison, but within an instance it involves 150 -- generic actual types, and in the presence of anonymous access types 151 -- it must examine the designated types. The argument Get_Inst is set to 152 -- True when this is a check against a formal access-to-subprogram type, 153 -- indicating that mapping of types is needed. 154 155 procedure Create_Extra_Formals (E : Entity_Id); 156 -- For each parameter of a subprogram or entry that requires an additional 157 -- formal (such as for access parameters and indefinite discriminated 158 -- parameters), creates the appropriate formal and attach it to its 159 -- associated parameter. Each extra formal will also be appended to 160 -- the end of Subp's parameter list (with each subsequent extra formal 161 -- being attached to the preceding extra formal). 162 163 function Find_Corresponding_Spec 164 (N : Node_Id; 165 Post_Error : Boolean := True) return Entity_Id; 166 -- Use the subprogram specification in the body to retrieve the previous 167 -- subprogram declaration, if any. 168 169 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean; 170 -- Determine whether two callable entities (subprograms, entries, 171 -- literals) are fully conformant (RM 6.3.1(17)) 172 173 function Fully_Conformant_Expressions 174 (Given_E1 : Node_Id; 175 Given_E2 : Node_Id; 176 Report : Boolean := False) return Boolean; 177 -- Determines if two (non-empty) expressions are fully conformant 178 -- as defined by (RM 6.3.1(18-21)) 179 180 function Fully_Conformant_Discrete_Subtypes 181 (Given_S1 : Node_Id; 182 Given_S2 : Node_Id) return Boolean; 183 -- Determines if two subtype definitions are fully conformant. Used 184 -- for entry family conformance checks (RM 6.3.1 (24)). 185 186 procedure Install_Entity (E : Entity_Id); 187 -- Place a single entity on the visibility chain 188 189 procedure Install_Formals (Id : Entity_Id); 190 -- On entry to a subprogram body, make the formals visible. Note that 191 -- simply placing the subprogram on the scope stack is not sufficient: 192 -- the formals must become the current entities for their names. This 193 -- procedure is also used to get visibility to the formals when analyzing 194 -- preconditions and postconditions appearing in the spec. 195 196 function Is_Interface_Conformant 197 (Tagged_Type : Entity_Id; 198 Iface_Prim : Entity_Id; 199 Prim : Entity_Id) return Boolean; 200 -- Returns true if both primitives have a matching name (including support 201 -- for names of inherited private primitives --which have suffix 'P'), they 202 -- are type conformant, and Prim is defined in the scope of Tagged_Type. 203 -- Special management is done for functions returning interfaces. 204 205 procedure List_Inherited_Pre_Post_Aspects (E : Entity_Id); 206 -- E is the entity for a subprogram or generic subprogram spec. This call 207 -- lists all inherited Pre/Post aspects if List_Inherited_Pre_Post is True. 208 209 procedure May_Need_Actuals (Fun : Entity_Id); 210 -- Flag functions that can be called without parameters, i.e. those that 211 -- have no parameters, or those for which defaults exist for all parameters 212 -- Used for subprogram declarations and for access subprogram declarations, 213 -- where they apply to the anonymous designated type. On return the flag 214 -- Set_Needs_No_Actuals is set appropriately in Fun. 215 216 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean; 217 -- Determine whether two callable entities (subprograms, entries, 218 -- literals) are mode conformant (RM 6.3.1(15)) 219 220 procedure New_Overloaded_Entity 221 (S : Entity_Id; 222 Derived_Type : Entity_Id := Empty); 223 -- Process new overloaded entity. Overloaded entities are created by 224 -- enumeration type declarations, subprogram specifications, entry 225 -- declarations, and (implicitly) by type derivations. If Derived_Type 226 -- is non-empty then this is a subprogram derived for that type. 227 228 procedure Process_Formals (T : List_Id; Related_Nod : Node_Id); 229 -- Enter the formals in the scope of the subprogram or entry, and 230 -- analyze default expressions if any. The implicit types created for 231 -- access parameter are attached to the Related_Nod which comes from the 232 -- context. 233 234 procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id); 235 -- If there is a separate spec for a subprogram or generic subprogram, the 236 -- formals of the body are treated as references to the corresponding 237 -- formals of the spec. This reference does not count as an actual use of 238 -- the formal, in order to diagnose formals that are unused in the body. 239 -- This procedure is also used in renaming_as_body declarations, where 240 -- the formals of the specification must be treated as body formals that 241 -- correspond to the previous subprogram declaration, and not as new 242 -- entities with their defining entry in the cross-reference information. 243 244 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id); 245 -- If the formals of a subprogram are unconstrained, build a subtype 246 -- declaration that uses the bounds or discriminants of the actual to 247 -- construct an actual subtype for them. This is an optimization that 248 -- is done only in some cases where the actual subtype cannot change 249 -- during execution of the subprogram. By setting the actual subtype 250 -- once, we avoid recomputing it unnecessarily. 251 252 procedure Set_Formal_Mode (Formal_Id : Entity_Id); 253 -- Set proper Ekind to reflect formal mode (in, out, in out) 254 255 function Subtype_Conformant 256 (New_Id : Entity_Id; 257 Old_Id : Entity_Id; 258 Skip_Controlling_Formals : Boolean := False) return Boolean; 259 -- Determine whether two callable entities (subprograms, entries, literals) 260 -- are subtype conformant (RM 6.3.1(16)). Skip_Controlling_Formals is True 261 -- when checking the conformance of a subprogram that implements an 262 -- interface operation. In that case, only the non-controlling formals 263 -- can (and must) be examined. 264 265 function Type_Conformant 266 (New_Id : Entity_Id; 267 Old_Id : Entity_Id; 268 Skip_Controlling_Formals : Boolean := False) return Boolean; 269 -- Determine whether two callable entities (subprograms, entries, literals) 270 -- are type conformant (RM 6.3.1(14)). Skip_Controlling_Formals is True 271 -- when checking the conformance of a subprogram that implements an 272 -- interface operation. In that case, only the non-controlling formals 273 -- can (and must) be examined. 274 275 procedure Valid_Operator_Definition (Designator : Entity_Id); 276 -- Verify that an operator definition has the proper number of formals 277 278end Sem_Ch6; 279