1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2007, Free Software Foundation, Inc. --
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 2, 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 COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- As a special exception, if other files instantiate generics from this --
23 -- unit, or you link this unit with other files to produce an executable, --
24 -- this unit does not by itself cause the resulting executable to be --
25 -- covered by the GNU General Public License. This exception does not --
26 -- however invalidate any other reasons why the executable file might be --
27 -- covered by the GNU Public License. --
29 -- GNAT was originally developed by the GNAT team at New York University. --
30 -- Extensive contributions were provided by Ada Core Technologies Inc. --
32 ------------------------------------------------------------------------------
34 -- This package contains routines for accessing and outputting the library
35 -- information. It contains the routine to load subsidiary units.
38 with Namet; use Namet;
40 with Types; use Types;
44 --------------------------------------------
45 -- General Approach to Library Management --
46 --------------------------------------------
48 -- As described in GNote #1, when a unit is compiled, all its subsidiary
49 -- units are recompiled, including the following:
51 -- (a) Corresponding spec for a body
52 -- (b) Parent spec of a child library spec
54 -- (d) Parent body of a subunit
55 -- (e) Subunits corresponding to any specified stubs
56 -- (f) Bodies of inlined subprograms that are called
57 -- (g) Bodies of generic subprograms or packages that are instantiated
58 -- (h) Bodies of packages containing either of the above two items
59 -- (i) Specs and bodies of runtime units
60 -- (j) Parent specs for with'ed child library units
62 -- If a unit is being compiled only for syntax checking, then no subsidiary
63 -- units are loaded, the syntax check applies only to the main unit,
64 -- i.e. the one contained in the source submitted to the library.
66 -- If a unit is being compiled for syntax and semantic checking, then only
67 -- cases (a)-(d) loads are performed, since the full semantic checking can
68 -- be carried out without needing (e)-(i) loads. In this case no object
69 -- file, or library information file, is generated, so the missing units
70 -- do not affect the results.
72 -- Specifications of library subprograms, subunits, and generic specs
73 -- and bodies, can only be compiled in syntax/semantic checking mode,
74 -- since no code is ever generated directly for these units. In the case
75 -- of subunits, only the compilation of the ultimate parent unit generates
76 -- actual code. If a subunit is submitted to the compiler in syntax/
77 -- semantic checking mode, the parent (or parents in the nested case) are
78 -- semantically checked only up to the point of the corresponding stub.
80 -- If code is being generated, then all the above units are required,
81 -- although the need for bodies of inlined procedures can be suppressed
82 -- by the use of a switch that sets the mode to ignore pragma Inline
85 -- The two main sections of the front end, Par and Sem, are recursive.
86 -- Compilation proceeds unit by unit making recursive calls as necessary.
87 -- The process is controlled from the GNAT main program, which makes calls
88 -- to Par and Sem sequence for the main unit.
90 -- Par parses the given unit, and then, after the parse is complete, uses
91 -- the Par.Load subprogram to load all its subsidiary units in categories
92 -- (a)-(d) above, installing pointers to the loaded units in the parse
93 -- tree, as described in a later section of this spec. If any of these
94 -- required units is missing, a fatal error is signalled, so that no
95 -- attempt is made to run Sem in such cases, since it is assumed that
96 -- too many cascaded errors would result, and the confusion would not
99 -- Following the call to Par on the main unit, the entire tree of required
100 -- units is thus loaded, and Sem is called on the main unit. The parameter
101 -- passed to Sem is the unit to be analyzed. The visibility table, which
102 -- is a single global structure, starts out containing only the entries
103 -- for the visible entities in Standard. Every call to Sem establishes a
104 -- new scope stack table, pushing an entry for Standard on entry to provide
105 -- the proper initial scope environment.
107 -- Sem first proceeds to perform semantic analysis on the currently loaded
110 -- In the case of a body (case (a) above), Sem analyzes the corresponding
111 -- spec, using a recursive call to Sem. As is always expected to be the
112 -- case with calls to Sem, any entities installed in the visibility table
113 -- are removed on exit from Sem, so that these entities have to be
114 -- reinstalled on return to continue the analysis of the body which of
115 -- course needs visibility of these entities.
117 -- In the case of the parent of a child spec (case (b) above), a similar
118 -- call is made to Sem to analyze the parent. Again, on return, the
119 -- entities from the analyzed parent spec have to be installed in the
120 -- visibility table of the caller (the child unit), which must have
121 -- visibility to the entities in its parent spec.
123 -- For with'ed specs (case (c) above), a recursive call to Sem is made
124 -- to analyze each spec in turn. After all the spec's have been analyzed,
125 -- but not till that point, the entities from all the with'ed units are
126 -- reinstalled in the visibility table so that the caller can proceed
127 -- with the analysis of the unit doing the with's with the necessary
128 -- entities made either potentially use visible or visible by selection
131 -- Case (d) arises when Sem is passed a subunit to analyze. This means
132 -- that the main unit is a subunit, and the unit passed to Sem is either
133 -- the main unit, or one of its ancestors that is still a subunit. Since
134 -- analysis must start at the top of the tree, Sem essentially cancels
135 -- the current call by immediately making a call to analyze the parent
136 -- (when this call is finished it immediately returns, so logically this
137 -- call is like a goto). The subunit will then be analyzed at the proper
138 -- time as described for the stub case. Note that we also turn off the
139 -- indication that code should be generated in this case, since the only
140 -- time we generate code for subunits is when compiling the main parent.
142 -- Case (e), subunits corresponding to stubs, are handled as the stubs
143 -- are encountered. There are three sub-cases:
145 -- If the subunit has already been loaded, then this means that the
146 -- main unit was a subunit, and we are back on our way down to it
147 -- after following the initial processing described for case (d).
148 -- In this case we analyze this particular subunit, as described
149 -- for the case where we are generating code, but when we get back
150 -- we are all done, since the rest of the parent is irrelevant. To
151 -- get out of the parent, we raise the exception Subunit_Found, which
152 -- is handled at the outer level of Sem.
154 -- The cases where the subunit has not already been loaded correspond
155 -- to cases where the main unit was a parent. In this case the action
156 -- depends on whether or not we are generating code. If we are not
157 -- generating code, then this is the case where we can simply ignore
158 -- the subunit, since in checking mode we don't even want to insist
159 -- that the subunit exist, much less waste time checking it.
161 -- If we are generating code, then we need to load and analyze
162 -- all subunits. This is achieved with a call to Lib.Load to load
163 -- and parse the unit, followed by processing that installs the
164 -- context clause of the subunit, analyzes the subunit, and then
165 -- removes the context clause (from the visibility chains of the
166 -- parent). Note that we do *not* do a recursive call to Sem in
167 -- this case, precisely because we need to do the analysis of the
168 -- subunit with the current visibility table and scope stack.
170 -- Case (f) applies only to subprograms for which a pragma Inline is
171 -- given, providing that the compiler is operating in the mode where
172 -- pragma Inline's are activated. When the expander encounters a call
173 -- to such a subprogram, it loads the body of the subprogram if it has
174 -- not already been loaded, and calls Sem to process it.
176 -- Case (g) is similar to case (f), except that the body of a generic
177 -- is unconditionally required, regardless of compiler mode settings.
178 -- As in the subprogram case, when the expander encounters a generic
179 -- instantiation, it loads the generic body of the subprogram if it
180 -- has not already been loaded, and calls Sem to process it.
182 -- Case (h) arises when a package contains either an inlined subprogram
183 -- which is called, or a generic which is instantiated. In this case the
184 -- body of the package must be loaded and analyzed with a call to Sem.
186 -- Case (i) is handled by adding implicit with clauses to the context
187 -- clauses of all units that potentially reference the relevant runtime
188 -- entities. Note that since we have the full set of units available,
189 -- the parser can always determine the set of runtime units that is
190 -- needed. These with clauses do not have associated use clauses, so
191 -- all references to the entities must be by selection. Once the with
192 -- clauses have been added, subsequent processing is as for normal
195 -- Case (j) is also handled by adding appropriate implicit with clauses
196 -- to any unit that withs a child unit. Again there is no use clause,
197 -- and subsequent processing proceeds as for an explicit with clause.
199 -- Sem thus completes the loading of all required units, except those
200 -- required for inline subprogram bodies or inlined generics. If any
201 -- of these load attempts fails, then the expander will not be called,
202 -- even if code was to be generated. If the load attempts all succeed
203 -- then the expander is called, though the attempt to generate code may
204 -- still fail if an error occurs during a load attempt for an inlined
205 -- body or a generic body.
207 -------------------------------------------
208 -- Special Handling of Subprogram Bodies --
209 -------------------------------------------
211 -- A subprogram body (in an adb file) may stand for both a spec and a
212 -- body. A simple model (and one that was adopted through version 2.07),
213 -- is simply to assume that such an adb file acts as its own spec if no
214 -- ads file is present.
216 -- However, this is not correct. RM 10.1.4(4) requires that such a body
217 -- act as a spec unless a subprogram declaration of the same name is
218 -- already present. The correct interpretation of this in GNAT library
219 -- terms is to ignore an existing ads file of the same name unless this
220 -- ads file contains a subprogram declaration with the same name.
222 -- If there is an ads file with a unit other than a subprogram declaration
223 -- with the same name, then a fatal message is output, noting that this
224 -- irrelevant file must be deleted before the body can be compiled. See
225 -- ACVC test CA1020D to see how this processing is required.
231 Current_Sem_Unit : Unit_Number_Type := Main_Unit;
232 -- Unit number of unit currently being analyzed/expanded. This is set when
233 -- ever a new unit is entered, saving and restoring the old value, so that
234 -- it always reflects the unit currently being analyzed. The initial value
235 -- of Main_Unit ensures that a proper value is set initially, and in
236 -- particular for analysis of configuration pragmas in gnat.adc.
238 Main_Unit_Entity : Entity_Id;
239 -- Entity of main unit, same as Cunit_Entity (Main_Unit) except where
240 -- Main_Unit is a body with a separate spec, in which case it is the
241 -- entity for the spec.
247 -- The units table has an entry for each unit (source file) read in by the
248 -- current compilation. The table is indexed by the unit number value,
249 -- The first entry in the table, subscript Main_Unit, is for the main file.
250 -- Each entry in this units table contains the following data.
253 -- The name of the source file containing the unit. Set when the entry
254 -- is created by a call to Lib.Load, and then cannot be changed.
257 -- The index in the source file table of the corresponding source file.
258 -- Set when the entry is created by a call to Lib.Load and then cannot
262 -- The index of the unit within the file for multiple unit per file
263 -- mode. Set to zero in normal single unit per file mode.
266 -- This is copied from the Sloc field of the Enode argument passed
267 -- to Load_Unit. It refers to the enclosing construct which caused
268 -- this unit to be loaded, e.g. most typically the with clause that
269 -- referenced the unit, and is used for error handling in Par.Load.
272 -- This is the expected unit name for a file other than the main unit,
273 -- since these are cases where we load the unit using Lib.Load and we
274 -- know the unit that is expected. It must be the same as Unit_Name
275 -- if it is set (see test in Par.Load). Expected_Unit is set to
276 -- No_Name for the main unit.
279 -- The name of the unit. Initialized to No_Name by Lib.Load, and then
280 -- set by the parser when the unit is parsed to the unit name actually
281 -- found in the file (which should, in the absence of errors) be the
282 -- same name as Expected_Unit.
285 -- Pointer to the N_Compilation_Unit node. Initially set to Empty by
286 -- Lib.Load, and then reset to the required node by the parser when
287 -- the unit is parsed.
290 -- Pointer to the entity node for the compilation unit. Initially set
291 -- to Empty by Lib.Load, and then reset to the required entity by the
292 -- parser when the unit is parsed.
295 -- This is the number of the unit within the generated dependency
296 -- lines (D lines in the ALI file) which are sorted into alphabetical
297 -- order. The number is ones origin, so a value of 2 refers to the
298 -- second generated D line. The Dependency_Number values are set
299 -- as the D lines are generated, and are used to generate proper
300 -- unit references in the generated xref information.
303 -- A flag indicating if this unit was compiled with dynamic elaboration
304 -- checks specified (as the result of using the -gnatE compilation
305 -- option or a pragma Elaboration_Checks (Dynamic).
308 -- A flag that is initialized to False, and gets set to True if a fatal
309 -- error occurs during the processing of a unit. A fatal error is one
310 -- defined as serious enough to stop the next phase of the compiler
311 -- from running (i.e. fatal error during parsing stops semantics,
312 -- fatal error during semantics stops code generation). Note that
313 -- currently, errors of any kind cause Fatal_Error to be set, but
314 -- eventually perhaps only errors labeled as Fatal_Errors should be
315 -- this severe if we decide to try Sem on sources with minor errors.
318 -- This flag is set True for all units in the current file for which
319 -- code is to be generated. This includes the unit explicitly compiled,
320 -- together with its specification, and any subunits.
323 -- A Boolean flag, initially set to False when a unit entry is created,
324 -- and set to True if the unit defines a remote access to class wide
325 -- (RACW) object. This is used for controlling generation of the RA
326 -- attribute in the ali file.
329 -- N_String_Literal node from a valid pragma Ident that applies to
330 -- this unit. If no Ident pragma applies to the unit, then Empty.
333 -- A flag that is used to catch circular WITH dependencies. It is set
334 -- True when an entry is initially created in the file table, and set
335 -- False when the load is completed, or ends with an error.
338 -- This field is used to indicate the priority of a possible main
339 -- program, as set by a pragma Priority. A value of -1 indicates
340 -- that the default priority is to be used (and is also used for
341 -- entries that do not correspond to possible main programs).
344 -- This field holds a serial number used by New_Internal_Name to
345 -- generate unique temporary numbers on a unit by unit basis. The
346 -- only access to this field is via the Increment_Serial_Number
347 -- routine which increments the current value and returns it. This
348 -- serial number is separate for each unit.
351 -- This field holds the version of the unit, which is computed as
352 -- the exclusive or of the checksums of this unit, and all its
353 -- semantically dependent units. Access to the version number field
354 -- is not direct, but is done through the routines described below.
355 -- When a unit table entry is created, this field is initialized to
356 -- the checksum of the corresponding source file. Version_Update is
357 -- then called to reflect the contributions of any unit on which this
358 -- unit is semantically dependent.
360 -- The units table is reset to empty at the start of the compilation of
361 -- each main unit by Lib.Initialize. Entries are then added by calls to
362 -- the Lib.Load procedure. The following subprograms are used to access
363 -- and modify entries in the Units table. Individual entries are accessed
364 -- using a unit number value which ranges from Main_Unit (the first entry,
365 -- which is always for the current main unit) to Last_Unit.
367 Default_Main_Priority : constant Int := -1;
368 -- Value used in Main_Priority field to indicate default main priority
370 function Cunit (U : Unit_Number_Type) return Node_Id;
371 function Cunit_Entity (U : Unit_Number_Type) return Entity_Id;
372 function Dependency_Num (U : Unit_Number_Type) return Nat;
373 function Dynamic_Elab (U : Unit_Number_Type) return Boolean;
374 function Error_Location (U : Unit_Number_Type) return Source_Ptr;
375 function Expected_Unit (U : Unit_Number_Type) return Unit_Name_Type;
376 function Fatal_Error (U : Unit_Number_Type) return Boolean;
377 function Generate_Code (U : Unit_Number_Type) return Boolean;
378 function Ident_String (U : Unit_Number_Type) return Node_Id;
379 function Has_RACW (U : Unit_Number_Type) return Boolean;
380 function Loading (U : Unit_Number_Type) return Boolean;
381 function Main_Priority (U : Unit_Number_Type) return Int;
382 function Munit_Index (U : Unit_Number_Type) return Nat;
383 function Source_Index (U : Unit_Number_Type) return Source_File_Index;
384 function Unit_File_Name (U : Unit_Number_Type) return File_Name_Type;
385 function Unit_Name (U : Unit_Number_Type) return Unit_Name_Type;
386 -- Get value of named field from given units table entry
388 procedure Set_Cunit (U : Unit_Number_Type; N : Node_Id);
389 procedure Set_Cunit_Entity (U : Unit_Number_Type; E : Entity_Id);
390 procedure Set_Dynamic_Elab (U : Unit_Number_Type; B : Boolean := True);
391 procedure Set_Error_Location (U : Unit_Number_Type; W : Source_Ptr);
392 procedure Set_Fatal_Error (U : Unit_Number_Type; B : Boolean := True);
393 procedure Set_Generate_Code (U : Unit_Number_Type; B : Boolean := True);
394 procedure Set_Has_RACW (U : Unit_Number_Type; B : Boolean := True);
395 procedure Set_Ident_String (U : Unit_Number_Type; N : Node_Id);
396 procedure Set_Loading (U : Unit_Number_Type; B : Boolean := True);
397 procedure Set_Main_Priority (U : Unit_Number_Type; P : Int);
398 procedure Set_Unit_Name (U : Unit_Number_Type; N : Unit_Name_Type);
399 -- Set value of named field for given units table entry. Note that we
400 -- do not have an entry for each possible field, since some of the fields
401 -- can only be set by specialized interfaces (defined below).
403 function Version_Get (U : Unit_Number_Type) return Word_Hex_String;
404 -- Returns the version as a string with 8 hex digits (upper case letters)
406 function Last_Unit return Unit_Number_Type;
407 -- Unit number of last allocated unit
409 function Num_Units return Nat;
410 -- Number of units currently in unit table
412 procedure Remove_Unit (U : Unit_Number_Type);
413 -- Remove unit U from unit table. Currently this is effective only
414 -- if U is the last unit currently stored in the unit table.
416 function Entity_Is_In_Main_Unit (E : Entity_Id) return Boolean;
417 -- Returns True if the entity E is declared in the main unit, or, in
418 -- its corresponding spec, or one of its subunits. Entities declared
419 -- within generic instantiations return True if the instantiation is
420 -- itself "in the main unit" by this definition. Otherwise False.
422 function Get_Source_Unit (N : Node_Or_Entity_Id) return Unit_Number_Type;
423 pragma Inline (Get_Source_Unit);
424 function Get_Source_Unit (S : Source_Ptr) return Unit_Number_Type;
425 -- Return unit number of file identified by given source pointer value.
426 -- This call must always succeed, since any valid source pointer value
427 -- belongs to some previously loaded module. If the given source pointer
428 -- value is within an instantiation, this function returns the unit number
429 -- of the template, i.e. the unit containing the source code corresponding
430 -- to the given Source_Ptr value. The version taking a Node_Id argument, N,
431 -- simply applies the function to Sloc (N).
433 function Get_Code_Unit (N : Node_Or_Entity_Id) return Unit_Number_Type;
434 pragma Inline (Get_Code_Unit);
435 function Get_Code_Unit (S : Source_Ptr) return Unit_Number_Type;
436 -- This is like Get_Source_Unit, except that in the instantiation case,
437 -- it uses the location of the top level instantiation, rather than the
438 -- template, so it returns the unit number containing the code that
439 -- corresponds to the node N, or the source location S.
441 function In_Same_Source_Unit (N1, N2 : Node_Or_Entity_Id) return Boolean;
442 pragma Inline (In_Same_Source_Unit);
443 -- Determines if the two nodes or entities N1 and N2 are in the same
444 -- source unit, the criterion being that Get_Source_Unit yields the
445 -- same value for each argument.
447 function In_Same_Code_Unit (N1, N2 : Node_Or_Entity_Id) return Boolean;
448 pragma Inline (In_Same_Code_Unit);
449 -- Determines if the two nodes or entities N1 and N2 are in the same
450 -- code unit, the criterion being that Get_Code_Unit yields the same
451 -- value for each argument.
453 function In_Same_Extended_Unit (N1, N2 : Node_Or_Entity_Id) return Boolean;
454 pragma Inline (In_Same_Extended_Unit);
455 -- Determines if two nodes or entities N1 and N2 are in the same
456 -- extended unit, where an extended unit is defined as a unit and all
457 -- its subunits (considered recursively, i.e. subunits of subunits are
458 -- included). Returns true if S1 and S2 are in the same extended unit
459 -- and False otherwise.
461 function In_Same_Extended_Unit (S1, S2 : Source_Ptr) return Boolean;
462 pragma Inline (In_Same_Extended_Unit);
463 -- Determines if the two source locations S1 and S2 are in the same
464 -- extended unit, where an extended unit is defined as a unit and all
465 -- its subunits (considered recursively, i.e. subunits of subunits are
466 -- included). Returns true if S1 and S2 are in the same extended unit
467 -- and False otherwise.
469 function In_Extended_Main_Code_Unit
470 (N : Node_Or_Entity_Id) return Boolean;
471 -- Return True if the node is in the generated code of the extended main
472 -- unit, defined as the main unit, its specification (if any), and all
473 -- its subunits (considered recursively). Units for which this enquiry
474 -- returns True are those for which code will be generated. Nodes from
475 -- instantiations are included in the extended main unit for this call.
476 -- If the main unit is itself a subunit, then the extended main unit
477 -- includes its parent unit, and the parent unit spec if it is separate.
479 function In_Extended_Main_Code_Unit (Loc : Source_Ptr) return Boolean;
480 -- Same function as above, but argument is a source pointer rather
483 function In_Extended_Main_Source_Unit
484 (N : Node_Or_Entity_Id) return Boolean;
485 -- Return True if the node is in the source text of the extended main
486 -- unit, defined as the main unit, its specification (if any), and all
487 -- its subunits (considered recursively). Units for which this enquiry
488 -- returns True are those for which code will be generated. This differs
489 -- from In_Extended_Main_Code_Unit only in that instantiations are not
490 -- included for the purposes of this call. If the main unit is itself
491 -- a subunit, then the extended main unit includes its parent unit,
492 -- and the parent unit spec if it is separate.
494 function In_Extended_Main_Source_Unit (Loc : Source_Ptr) return Boolean;
495 -- Same function as above, but argument is a source pointer
497 function In_Predefined_Unit (N : Node_Or_Entity_Id) return Boolean;
498 -- Returns True if the given node or entity appears within the source text
499 -- of a predefined unit (i.e. within Ada, Interfaces, System or within one
500 -- of the descendent packages of one of these three packages).
502 function In_Predefined_Unit (S : Source_Ptr) return Boolean;
503 -- Same function as above but argument is a source pointer
505 function Earlier_In_Extended_Unit (S1, S2 : Source_Ptr) return Boolean;
506 -- Given two Sloc values for which In_Same_Extended_Unit is true,
507 -- determine if S1 appears before S2. Returns True if S1 appears before
508 -- S2, and False otherwise. The result is undefined if S1 and S2 are
509 -- not in the same extended unit.
511 function Compilation_Switches_Last return Nat;
512 -- Return the count of stored compilation switches
514 function Get_Compilation_Switch (N : Pos) return String_Ptr;
515 -- Return the Nth stored compilation switch, or null if less than N
516 -- switches have been stored. Used by ASIS and back ends written in Ada.
518 function Get_Cunit_Unit_Number (N : Node_Id) return Unit_Number_Type;
519 -- Return unit number of the unit whose N_Compilation_Unit node is the
520 -- one passed as an argument. This must always succeed since the node
521 -- could not have been built without making a unit table entry.
523 function Get_Cunit_Entity_Unit_Number
524 (E : Entity_Id) return Unit_Number_Type;
525 -- Return unit number of the unit whose compilation unit spec entity is
526 -- the one passed as an argument. This must always succeed since the
527 -- entity could not have been built without making a unit table entry.
529 function Increment_Serial_Number return Nat;
530 -- Increment Serial_Number field for current unit, and return the
531 -- incremented value.
533 procedure Synchronize_Serial_Number;
534 -- This function increments the Serial_Number field for the current unit
535 -- but does not return the incremented value. This is used when there
536 -- is a situation where one path of control increments a serial number
537 -- (using Increment_Serial_Number), and the other path does not and it is
538 -- important to keep the serial numbers synchronized in the two cases (e.g.
539 -- when the references in a package and a client must be kept consistent).
541 procedure Replace_Linker_Option_String
543 Match_String : String);
544 -- Replace an existing Linker_Option if the prefix Match_String matches,
545 -- otherwise call Store_Linker_Option_String.
547 procedure Store_Compilation_Switch (Switch : String);
548 -- Called to register a compilation switch, either front-end or back-end,
549 -- which may influence the generated output file(s). Switch is the text of
550 -- the switch to store (except that -fRTS gets changed back to --RTS).
552 procedure Disable_Switch_Storing;
553 -- Disable registration of switches by Store_Compilation_Switch. Used to
554 -- avoid registering switches added automatically by the gcc driver.
556 procedure Store_Linker_Option_String (S : String_Id);
557 -- This procedure is called to register the string from a pragma
558 -- Linker_Option. The argument is the Id of the string to register.
560 procedure Initialize;
561 -- Initialize internal tables
564 -- Lock internal tables before calling back end
567 -- Unlock internal tables, in cases where the back end needs to modify them
570 -- Initializes internal tables from current tree file using the relevant
571 -- Table.Tree_Read routines.
573 procedure Tree_Write;
574 -- Writes out internal tables to current tree file using the relevant
575 -- Table.Tree_Write routines.
577 function Is_Loaded (Uname : Unit_Name_Type) return Boolean;
578 -- Determines if unit with given name is already loaded, i.e. there is
579 -- already an entry in the file table with this unit name for which the
580 -- corresponding file was found and parsed. Note that the Fatal_Error flag
581 -- of this entry must be checked before proceeding with further processing.
583 procedure Version_Referenced (S : String_Id);
584 -- This routine is called from Exp_Attr to register the use of a Version
585 -- or Body_Version attribute. The argument is the external name used to
586 -- access the version string.
588 procedure List (File_Names_Only : Boolean := False);
589 -- Lists units in active library (i.e. generates output consisting of a
590 -- sorted listing of the units represented in File table, except for the
591 -- main unit). If File_Names_Only is set to True, then the list includes
592 -- only file names, and no other information. Otherwise the unit name and
593 -- time stamp are also output. File_Names_Only also restricts the list to
594 -- exclude any predefined files.
596 function Generic_Separately_Compiled (E : Entity_Id) return Boolean;
597 -- This is the old version of tbe documentation of this function:
599 -- Most generic units must be separately compiled. Since we always use
600 -- macro substitution for generics, the resulting object file is a dummy
601 -- one with no code, but the ali file has the normal form, and we need
602 -- this ali file so that the binder can work out a correct order of
603 -- elaboration. However, we do not need to separate compile generics
604 -- if the generic files are language defined, since in this case there
605 -- are no order of elaborration problems, and we can simply incorporate
606 -- the context clause of the generic unit into the client. There are two
607 -- reasons for making this exception for predefined units. First, clearly
608 -- it is more efficient not to introduce extra unnecessary files. Second,
609 -- the old version of GNAT did not compile any generic units. That was
610 -- clearly incorrect in some cases of complex order of elaboration and
611 -- was fixed in version 3.10 of GNAT. However, the transition would have
612 -- caused bootstrap path problems in the case of generics used in the
613 -- compiler itself. The only such generics are predefined ones. This
614 -- function returns True if the given generic unit entity E is for a
615 -- generic unit that should be separately compiled, and false otherwise.
617 -- Now GNAT can compile any generic unit including predefined ones, but
618 -- because of the backward compatibility (to keep the ability to use old
619 -- compiler versions to build GNAT) compiling library generics is an
620 -- option. That is, now GNAT compiles a library generic as an ordinary
621 -- unit, but it also can build an exeutable in case if its library contains
622 -- some (or all) predefined generics non compiled. See 9628-002 for the
623 -- description of changes to be done to get rid of a special processing of
626 -- So now this function returns TRUE if a generic MUST be separately
627 -- compiled with the current approach.
629 function Generic_Separately_Compiled
630 (Sfile : File_Name_Type) return Boolean;
631 -- Same as the previous function, but works directly on a unit file name
634 pragma Inline (Cunit);
635 pragma Inline (Cunit_Entity);
636 pragma Inline (Dependency_Num);
637 pragma Inline (Fatal_Error);
638 pragma Inline (Generate_Code);
639 pragma Inline (Has_RACW);
640 pragma Inline (Increment_Serial_Number);
641 pragma Inline (Loading);
642 pragma Inline (Main_Priority);
643 pragma Inline (Munit_Index);
644 pragma Inline (Set_Cunit);
645 pragma Inline (Set_Cunit_Entity);
646 pragma Inline (Set_Fatal_Error);
647 pragma Inline (Set_Generate_Code);
648 pragma Inline (Set_Has_RACW);
649 pragma Inline (Set_Loading);
650 pragma Inline (Set_Main_Priority);
651 pragma Inline (Set_Unit_Name);
652 pragma Inline (Source_Index);
653 pragma Inline (Unit_File_Name);
654 pragma Inline (Unit_Name);
656 type Unit_Record is record
657 Unit_File_Name : File_Name_Type;
658 Unit_Name : Unit_Name_Type;
660 Expected_Unit : Unit_Name_Type;
661 Source_Index : Source_File_Index;
663 Cunit_Entity : Entity_Id;
664 Dependency_Num : Int;
665 Ident_String : Node_Id;
669 Error_Location : Source_Ptr;
670 Fatal_Error : Boolean;
671 Generate_Code : Boolean;
673 Dynamic_Elab : Boolean;
677 -- The following representation clause ensures that the above record
678 -- has no holes. We do this so that when instances of this record are
679 -- written by Tree_Gen, we do not write uninitialized values to the file.
681 for Unit_Record use record
682 Unit_File_Name at 0 range 0 .. 31;
683 Unit_Name at 4 range 0 .. 31;
684 Munit_Index at 8 range 0 .. 31;
685 Expected_Unit at 12 range 0 .. 31;
686 Source_Index at 16 range 0 .. 31;
687 Cunit at 20 range 0 .. 31;
688 Cunit_Entity at 24 range 0 .. 31;
689 Dependency_Num at 28 range 0 .. 31;
690 Ident_String at 32 range 0 .. 31;
691 Main_Priority at 36 range 0 .. 31;
692 Serial_Number at 40 range 0 .. 31;
693 Version at 44 range 0 .. 31;
694 Error_Location at 48 range 0 .. 31;
695 Fatal_Error at 52 range 0 .. 7;
696 Generate_Code at 53 range 0 .. 7;
697 Has_RACW at 54 range 0 .. 7;
698 Dynamic_Elab at 55 range 0 .. 7;
699 Loading at 56 range 0 .. 31;
702 for Unit_Record'Size use 60 * 8;
703 -- This ensures that we did not leave out any fields
705 package Units is new Table.Table (
706 Table_Component_Type => Unit_Record,
707 Table_Index_Type => Unit_Number_Type,
708 Table_Low_Bound => Main_Unit,
709 Table_Initial => Alloc.Units_Initial,
710 Table_Increment => Alloc.Units_Increment,
711 Table_Name => "Units");
713 -- The following table stores strings from pragma Linker_Option lines
715 type Linker_Option_Entry is record
717 -- The string for the linker option line
719 Unit : Unit_Number_Type;
720 -- The unit from which the linker option comes
723 package Linker_Option_Lines is new Table.Table (
724 Table_Component_Type => Linker_Option_Entry,
725 Table_Index_Type => Integer,
726 Table_Low_Bound => 1,
727 Table_Initial => Alloc.Linker_Option_Lines_Initial,
728 Table_Increment => Alloc.Linker_Option_Lines_Increment,
729 Table_Name => "Linker_Option_Lines");
731 -- The following table records the compilation switches used to compile
732 -- the main unit. The table includes only switches and excludes -quiet,
733 -- -dumpbase, and -o switches, since the latter are typically artifacts
734 -- of the gcc/gnat1 interface.
736 -- This table is set as part of the compiler argument scanning in
737 -- Back_End. It can also be reset in -gnatc mode from the data in an
738 -- existing ali file, and is read and written by the Tree_Read and
739 -- Tree_Write routines for ASIS.
741 package Compilation_Switches is new Table.Table (
742 Table_Component_Type => String_Ptr,
743 Table_Index_Type => Nat,
744 Table_Low_Bound => 1,
746 Table_Increment => 100,
747 Table_Name => "Compilation_Switches");
749 Load_Msg_Sloc : Source_Ptr;
750 -- Location for placing error messages (a token in the main source text)
751 -- This is set from Sloc (Enode) by Load only in the case where this Sloc
752 -- is in the main source file. This ensures that not found messages and
753 -- circular dependency messages reference the original with in this source.
755 type Unit_Ref_Table is array (Pos range <>) of Unit_Number_Type;
756 -- Type to hold list of indirect references to unit number table
758 type Load_Stack_Entry is record
759 Unit_Number : Unit_Number_Type;
760 From_Limited_With : Boolean;
763 -- The Load_Stack table contains a list of unit numbers (indices into the
764 -- unit table) of units being loaded on a single dependency chain, and a
765 -- flag to indicate whether this unit is loaded through a limited_with
766 -- clause. The First entry is the main unit. The second entry, if present
767 -- is a unit on which the first unit depends, etc. This stack is used to
768 -- generate error messages showing the dependency chain if a file is not
769 -- found, or whether a true circular dependency exists. The Load_Unit
770 -- function makes an entry in this table when it is called, and removes
771 -- the entry just before it returns.
773 package Load_Stack is new Table.Table (
774 Table_Component_Type => Load_Stack_Entry,
775 Table_Index_Type => Int,
776 Table_Low_Bound => 0,
777 Table_Initial => Alloc.Load_Stack_Initial,
778 Table_Increment => Alloc.Load_Stack_Increment,
779 Table_Name => "Load_Stack");
781 procedure Sort (Tbl : in out Unit_Ref_Table);
782 -- This procedure sorts the given unit reference table in order of
783 -- ascending unit names, where the ordering relation is as described
784 -- by the comparison routines provided by package Uname.
786 -- The Version_Ref table records Body_Version and Version attribute
787 -- references. The entries are simply the strings for the external
788 -- names that correspond to the referenced values.
790 package Version_Ref is new Table.Table (
791 Table_Component_Type => String_Id,
792 Table_Index_Type => Nat,
793 Table_Low_Bound => 1,
795 Table_Increment => 100,
796 Table_Name => "Version_Ref");