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[official-gcc.git] / gcc / ada / targparm.ads
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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT RUN-TIME COMPONENTS --
4 -- --
5 -- T A R G P A R M --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 1999-2017, 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 ------------------------------------------------------------------------------
26 -- This package obtains parameters from the target runtime version of System,
27 -- to indicate parameters relevant to the target environment.
29 -- Conceptually, these parameters could be obtained using rtsfind, but
30 -- we do not do this for four reasons:
32 -- 1. Compiling System for every compilation wastes time
34 -- 2. This compilation impedes debugging by adding extra compile steps
36 -- 3. There are recursion problems coming from compiling System itself
37 -- or any of its children.
39 -- 4. The binder also needs the parameters, and we do not want to have
40 -- to drag a lot of front end stuff into the binder.
42 -- For all these reasons, we read in the source of System, and then scan
43 -- it at the text level to extract the parameter values.
45 -- Note however, that later on, when the ali file is written, we make sure
46 -- that the System file is at least parsed, so that the checksum is properly
47 -- computed and set in the ali file. This partially negates points 1 and 2
48 -- above although just parsing is quick and does not impact debugging much.
50 -- The parameters acquired by this routine from system.ads fall into four
51 -- categories:
53 -- 1. Configuration pragmas, that must appear at the start of the file.
54 -- Any such pragmas automatically apply to any unit compiled in the
55 -- presence of this system file. Only a limited set of such pragmas
56 -- may appear as documented in the corresponding section below.
58 -- 2. Target parameters. These are boolean constants that are defined
59 -- in the private part of the package giving fixed information
60 -- about the target architecture, and the capabilities of the
61 -- code generator and run-time library.
63 -- 3. Identification information. This is an optional string constant
64 -- that gives the name of the run-time library configuration. This
65 -- line may be omitted for a version of system.ads to be used with
66 -- the full Ada 95 run time.
68 -- 4. Other characteristics of package System. At the current time the
69 -- only item in this category is whether type Address is private.
71 with Rident; use Rident;
72 with Namet; use Namet;
73 with Types; use Types;
75 package Targparm is
77 ---------------------------
78 -- Configuration Pragmas --
79 ---------------------------
81 -- The following switches get set if the corresponding configuration
82 -- pragma is scanned from the source of system.ads. No other pragmas
83 -- are permitted to appear at the start of the system.ads source file.
85 -- If a pragma Discard_Names appears, then Opt.Global_Discard_Names is
86 -- set to True to indicate that all units must be compiled in this mode.
88 -- If a pragma Locking_Policy appears, then Opt.Locking_Policy is set
89 -- to the first character of the policy name, and Opt.Locking_Policy_Sloc
90 -- is set to System_Location.
92 -- If a pragma Normalize_Scalars appears, then Opt.Normalize_Scalars
93 -- is set True, as well as Opt.Init_Or_Norm_Scalars.
95 -- If a pragma Queuing_Policy appears, then Opt.Queuing_Policy is set
96 -- to the first character of the policy name, and Opt.Queuing_Policy_Sloc
97 -- is set to System_Location.
99 -- If a pragma Task_Dispatching_Policy appears, then the flag
100 -- Opt.Task_Dispatching_Policy is set to the first character of the
101 -- policy name, and Opt.Task_Dispatching_Policy_Sloc is set to
102 -- System_Location.
104 -- If a pragma Polling (On) appears, then the flag Opt.Polling_Required
105 -- is set to True.
107 -- If a pragma Detect_Blocking appears, then the flag Opt.Detect_Blocking
108 -- is set to True.
110 -- If a pragma Suppress_Exception_Locations appears, then the flag
111 -- Opt.Exception_Locations_Suppressed is set to True.
113 -- If a pragma Profile with a valid profile argument appears, then
114 -- the appropriate restrictions and policy flags are set.
116 -- The only other pragma allowed is a pragma Restrictions that specifies
117 -- a restriction that will be imposed on all units in the partition. Note
118 -- that in this context, only one restriction can be specified in a single
119 -- pragma, and the pragma must appear on its own on a single source line.
121 -- If package System contains exactly the line "type Address is private;"
122 -- then the flag Opt.Address_Is_Private is set True, otherwise this flag
123 -- is set False.
125 Restrictions_On_Target : Restrictions_Info := No_Restrictions;
126 -- Records restrictions specified by system.ads. Only the Set and Value
127 -- members are modified. The Violated and Count fields are never modified.
128 -- Note that entries can be set either by a pragma Restrictions or by
129 -- a pragma Profile.
131 -------------------
132 -- Run Time Name --
133 -------------------
135 -- This parameter should be regarded as read only by all clients of
136 -- of package. The only way they get modified is by calling the
137 -- Get_Target_Parameters routine which reads the values from a provided
138 -- text buffer containing the source of the system package.
140 -- The corresponding string constant is placed immediately at the start
141 -- of the private part of system.ads if is present, e.g. in the form:
143 -- Run_Time_Name : constant String := "Zero Footprint Run Time";
145 -- the corresponding messages will look something like
147 -- xxx not supported (Zero Footprint Run Time)
149 Run_Time_Name_On_Target : Name_Id := No_Name;
150 -- Set to appropriate names table entry Id value if a Run_Time_Name
151 -- string constant is defined in system.ads. This name is used only
152 -- for the configurable run-time case, and is used to parameterize
153 -- messages that complain about non-supported run-time features.
154 -- The name should contain only letters A-Z, digits 1-9, spaces,
155 -- and underscores.
157 --------------------------
158 -- Executable Extension --
159 --------------------------
161 Executable_Extension_On_Target : Name_Id := No_Name;
162 -- Executable extension on the target. This name is useful for setting
163 -- the executable extension in a dynamic way, e.g. depending on the
164 -- run time used, rather than using a configure-time macro as done by
165 -- Get_Target_Executable_Suffix. If not set (No_Name), instead use
166 -- System.OS_Lib.Get_Target_Executable_Suffix.
168 -----------------------
169 -- Target Parameters --
170 -----------------------
172 -- The following parameters correspond to the variables defined in the
173 -- private part of System (without the terminating _On_Target). Note
174 -- that it is required that all parameters defined here be specified
175 -- in the target specific version of system.ads. Thus, to add a new
176 -- parameter, add it to all system*.ads files. (There is a defaulting
177 -- mechanism, but we don't normally take advantage of it, as explained
178 -- below.)
180 -- The default values here are used if no value is found in system.ads.
181 -- This should normally happen if the special version of system.ads used
182 -- by the compiler itself is in use or if the value is only relevant to a
183 -- particular target (e.g. AAMP). The default values are suitable for use
184 -- in normal environments. This approach allows the possibility of new
185 -- versions of the compiler (possibly with new system parameters added)
186 -- being used to compile older versions of the compiler sources, as well as
187 -- avoiding duplicating values in all system-*.ads files for flags that are
188 -- used on a few platforms only.
190 -- All these parameters should be regarded as read only by all clients
191 -- of the package. The only way they get modified is by calling the
192 -- Get_Target_Parameters routine which reads the values from a provided
193 -- text buffer containing the source of the system package.
195 -------------------------------
196 -- Backend Arithmetic Checks --
197 -------------------------------
199 -- Divide and overflow checks are either done in the front end or
200 -- back end. The front end will generate checks when required unless
201 -- the corresponding parameter here is set to indicate that the back
202 -- end will generate the required checks (or that the checks are
203 -- automatically performed by the hardware in an appropriate form).
205 Backend_Divide_Checks_On_Target : Boolean := False;
206 -- Set True if the back end generates divide checks, or if the hardware
207 -- checks automatically. Set False if the front end must generate the
208 -- required tests using explicit expanded code.
210 Backend_Overflow_Checks_On_Target : Boolean := False;
211 -- Set True if the back end generates arithmetic overflow checks, or if
212 -- the hardware checks automatically. Set False if the front end must
213 -- generate the required tests using explicit expanded code.
215 -----------------------------------
216 -- Control of Exception Handling --
217 -----------------------------------
219 -- GNAT implements three methods of implementing exceptions:
221 -- Front-End Longjmp/Setjmp Exceptions
223 -- This approach uses longjmp/setjmp to handle exceptions. It
224 -- uses less storage, and can often propagate exceptions faster,
225 -- at the expense of (sometimes considerable) overhead in setting
226 -- up an exception handler.
228 -- The generation of the setjmp and longjmp calls is handled by
229 -- the front end of the compiler (this includes gigi in the case
230 -- of the standard GCC back end). It does not use any back end
231 -- support (such as the GCC3 exception handling mechanism). When
232 -- this approach is used, the compiler generates special exception
233 -- handlers for handling cleanups (AT-END actions) when an exception
234 -- is raised.
236 -- Back-End Zero Cost Exceptions
238 -- With this approach, the back end handles the generation and
239 -- handling of exceptions. For example, the GCC3 exception handling
240 -- mechanisms are used in this mode. The front end simply generates
241 -- code for explicit exception handlers, and AT-END cleanup handlers
242 -- are simply passed unchanged to the backend for generating cleanups
243 -- both in the exceptional and non-exceptional cases.
245 -- As the name implies, this approach uses a table-based mechanism,
246 -- which incurs no setup when entering a region covered by handlers
247 -- but requires complex unwinding to walk up the call chain and search
248 -- for handlers at propagation time.
250 -- Back-End Setjmp/Longjmp Exceptions
252 -- With this approach, the back end also handles the generation and
253 -- handling of exceptions, using setjmp/longjmp to set up receivers and
254 -- propagate. AT-END actions on exceptional paths are also taken care
255 -- of by the back end and the front end doesn't need to generate
256 -- explicit exception handlers for these.
258 -- Control of Available Methods and Defaults
260 -- The following switches specify whether we're using a front-end or a
261 -- back-end mechanism and whether this is a zero-cost or a sjlj scheme.
263 -- The per-switch default values correspond to the default value of
264 -- Opt.Exception_Mechanism.
266 ZCX_By_Default_On_Target : Boolean := False;
267 -- Indicates if zero cost scheme for exceptions
269 Frontend_Exceptions_On_Target : Boolean := True;
270 -- Indicates if we're using a front-end scheme for exceptions
272 ------------------------------------
273 -- Run-Time Library Configuration --
274 ------------------------------------
276 -- In configurable run-time mode, the system run-time may not support
277 -- the full Ada language. The effect of setting this switch is to let
278 -- the compiler know that it is not surprising (i.e. the system is not
279 -- misconfigured) if run-time library units or entities within units are
280 -- not present in the run-time.
282 Configurable_Run_Time_On_Target : Boolean := False;
283 -- Indicates that the system.ads file is for a configurable run-time
285 -- This has some specific effects as follows
287 -- The binder generates the gnat_argc/argv/envp variables in the
288 -- binder file instead of being imported from the run-time library.
289 -- If Command_Line_Args_On_Target is set to False, then the
290 -- generation of these variables is suppressed completely.
292 -- The binder generates the gnat_exit_status variable in the binder
293 -- file instead of being imported from the run-time library. If
294 -- Exit_Status_Supported_On_Target is set to False, then the
295 -- generation of this variable is suppressed entirely.
297 -- The routine __gnat_break_start is defined within the binder file
298 -- instead of being imported from the run-time library.
300 -- The variable __gnat_exit_status is generated within the binder file
301 -- instead of being imported from the run-time library.
303 Suppress_Standard_Library_On_Target : Boolean := False;
304 -- If this flag is True, then the standard library is not included by
305 -- default in the executable (see unit System.Standard_Library in file
306 -- s-stalib.ads for details of what this includes). This is for example
307 -- set True for the zero foot print case, where these files should not
308 -- be included by default.
310 -- This flag has some other related effects:
312 -- The generation of global variables in the bind file is suppressed,
313 -- with the exception of the priority of the environment task, which
314 -- is needed by the Ravenscar run-time.
316 -- The calls to __gnat_initialize and __gnat_finalize are omitted
318 -- All finalization and initialization (controlled types) is omitted
320 Preallocated_Stacks_On_Target : Boolean := False;
321 -- If this flag is True, then the expander preallocates all task stacks
322 -- at compile time. If the flag is False, then task stacks are not pre-
323 -- allocated, and task stack allocation is the responsibility of the
324 -- run-time (which typically delegates the task to the underlying
325 -- operating system environment).
327 ---------------------
328 -- Duration Format --
329 ---------------------
331 -- By default, type Duration is a 64-bit fixed-point type with a delta
332 -- and small of 10**(-9) (i.e. it is a count in nanoseconds). This flag
333 -- allows that standard format to be modified.
335 Duration_32_Bits_On_Target : Boolean := False;
336 -- If True, then Duration is represented in 32 bits and the delta and
337 -- small values are set to 20.0*(10**(-3)) (i.e. it is a count in units
338 -- of 20 milliseconds).
340 ------------------------------------
341 -- Back-End Code Generation Flags --
342 ------------------------------------
344 -- These flags indicate possible limitations in what the code generator
345 -- can handle. They will all be True for a full run-time, but one or more
346 -- of these may be false for a configurable run-time, and if a feature is
347 -- used at the source level, and the corresponding flag is false, then an
348 -- error message will be issued saying the feature is not supported.
350 Atomic_Sync_Default_On_Target : Boolean := True;
351 -- Access to atomic variables requires memory barrier synchronization in
352 -- the general case to ensure proper behavior when such accesses are used
353 -- on a multi-processor to synchronize tasks (e.g. by using spin locks).
354 -- The setting of this flag determines the default behavior. Normally this
355 -- is True, which will mean that appropriate synchronization instructions
356 -- are generated by default. If it is False, then the default will be that
357 -- these synchronization instructions are not generated. This may be a more
358 -- appropriate default in some cases, e.g. on embedded targets which do not
359 -- allow the possibility of multi-processors. The default can be overridden
360 -- using pragmas Enable/Disable_Atomic_Synchronization and also by use of
361 -- the corresponding debug flags -gnatd.e and -gnatd.d.
363 Support_Aggregates_On_Target : Boolean := True;
364 -- In the general case, the use of aggregates may generate calls
365 -- to run-time routines in the C library, including memset, memcpy,
366 -- memmove, and bcopy. This flag is set to True if these routines
367 -- are available. If any of these routines is not available, then
368 -- this flag is False, and the use of aggregates is not permitted.
370 Support_Atomic_Primitives_On_Target : Boolean := False;
371 -- If this flag is True, then the back-end support GCC built-in atomic
372 -- operations for memory model such as atomic load or atomic compare
373 -- exchange (see the GCC manual for more information). If the flag is
374 -- False, then the back-end doesn't provide this support. Note this flag is
375 -- set to True only if the target supports all atomic primitives up to 64
376 -- bits. ??? To be modified.
378 Support_Composite_Assign_On_Target : Boolean := True;
379 -- The assignment of composite objects other than small records and
380 -- arrays whose size is 64-bits or less and is set by an explicit
381 -- size clause may generate calls to memcpy, memmove, and bcopy.
382 -- If versions of all these routines are available, then this flag
383 -- is set to True. If any of these routines is not available, then
384 -- the flag is set False, and composite assignments are not allowed.
386 Support_Composite_Compare_On_Target : Boolean := True;
387 -- If this flag is True, then the back end supports bit-wise comparison
388 -- of composite objects for equality, either generating inline code or
389 -- calling appropriate (and available) run-time routines. If this flag
390 -- is False, then the back end does not provide this support, and the
391 -- front end uses component by component comparison for composites.
393 Support_Long_Shifts_On_Target : Boolean := True;
394 -- If True, the back end supports 64-bit shift operations. If False, then
395 -- the source program may not contain explicit 64-bit shifts. In addition,
396 -- the code generated for packed arrays will avoid the use of long shifts.
398 Support_Nondefault_SSO_On_Target : Boolean := True;
399 -- If True, the back end supports the non-default Scalar_Storage_Order
400 -- (i.e. allows non-confirming Scalar_Storage_Order attribute definition
401 -- clauses).
403 --------------------
404 -- Indirect Calls --
405 --------------------
407 Always_Compatible_Rep_On_Target : Boolean := True;
408 -- If True, the Can_Use_Internal_Rep flag (see Einfo) is set to False in
409 -- all cases. This corresponds to the traditional code generation
410 -- strategy. False allows the front end to choose a policy that partly or
411 -- entirely eliminates dynamically generated trampolines.
413 -------------------------------
414 -- Control of Stack Checking --
415 -------------------------------
417 -- GNAT provides three methods of implementing exceptions:
419 -- GCC Probing Mechanism
421 -- This approach uses the standard GCC mechanism for
422 -- stack checking. The method assumes that accessing
423 -- storage immediately beyond the end of the stack
424 -- will result in a trap that is converted to a storage
425 -- error by the runtime system. This mechanism has
426 -- minimal overhead, but requires complex hardware,
427 -- operating system and run-time support. Probing is
428 -- the default method where it is available. The stack
429 -- size for the environment task depends on the operating
430 -- system and cannot be set in a system-independent way.
432 -- GCC Stack-limit Mechanism
434 -- This approach uses the GCC stack limits mechanism.
435 -- It relies on comparing the stack pointer with the
436 -- values of a global symbol. If the check fails, a
437 -- trap is explicitly generated. The advantage is
438 -- that the mechanism requires no memory protection,
439 -- but operating system and run-time support are
440 -- needed to manage the per-task values of the symbol.
441 -- This is the default method after probing where it
442 -- is available.
444 -- GNAT Stack-limit Checking
446 -- This method relies on comparing the stack pointer
447 -- with per-task stack limits. If the check fails, an
448 -- exception is explicitly raised. The advantage is
449 -- that the method requires no extra system dependent
450 -- runtime support and can be used on systems without
451 -- memory protection as well, but at the cost of more
452 -- overhead for doing the check. This is the fallback
453 -- method if the above two are not supported.
455 Stack_Check_Probes_On_Target : Boolean := False;
456 -- Indicates if the GCC probing mechanism is used
458 Stack_Check_Limits_On_Target : Boolean := False;
459 -- Indicates if the GCC stack-limit mechanism is used
461 -- Both flags cannot be simultaneously set to True. If neither
462 -- is, the target independent fallback method is used.
464 Stack_Check_Default_On_Target : Boolean := False;
465 -- Indicates if stack checking is on by default
467 ----------------------------
468 -- Command Line Arguments --
469 ----------------------------
471 -- For most ports of GNAT, command line arguments are supported. The
472 -- following flag is set to False for targets that do not support
473 -- command line arguments (VxWorks and AAMP). Note that support of
474 -- command line arguments is not required on such targets (RM A.15(13)).
476 Command_Line_Args_On_Target : Boolean := True;
477 -- Set False if no command line arguments on target. Note that if this
478 -- is False in with Configurable_Run_Time_On_Target set to True, then
479 -- this causes suppression of generation of the argv/argc variables
480 -- used to record command line arguments.
482 -- Similarly, most ports support the use of an exit status, but AAMP
483 -- is an exception (as allowed by RM A.15(18-20))
485 Exit_Status_Supported_On_Target : Boolean := True;
486 -- Set False if returning of an exit status is not supported on target.
487 -- Note that if this False in with Configurable_Run_Time_On_Target
488 -- set to True, then this causes suppression of the gnat_exit_status
489 -- variable used to record the exit status.
491 -----------------------
492 -- Main Program Name --
493 -----------------------
495 -- When the binder generates the main program to be used to create the
496 -- executable, the main program name is main by default (to match the
497 -- usual Unix practice). If this parameter is set to True, then the
498 -- name is instead by default taken from the actual Ada main program
499 -- name (just the name of the child if the main program is a child unit).
500 -- In either case, this value can be overridden using -M name.
502 Use_Ada_Main_Program_Name_On_Target : Boolean := False;
503 -- Set True to use the Ada main program name as the main name
505 ----------------------------------------------
506 -- Boolean-Valued Floating-Point Attributes --
507 ----------------------------------------------
509 -- The constants below give the values for representation oriented
510 -- floating-point attributes that are the same for all float types
511 -- on the target. These are all boolean values.
513 -- A value is only True if the target reliably supports the corresponding
514 -- feature. Reliably here means that support is guaranteed for all
515 -- possible settings of the relevant compiler switches (like -mieee),
516 -- since we cannot control the user setting of those switches.
518 -- The attributes cannot dependent on the current setting of compiler
519 -- switches, since the values must be static and consistent throughout
520 -- the partition. We probably should add such consistency checks in future,
521 -- but for now we don't do this.
523 -- Note: the compiler itself does not use floating-point, so the
524 -- settings of the defaults here are not really relevant.
526 -- Note: in some cases, proper support of some of these floating point
527 -- features may require a specific switch (e.g. -mieee on the Alpha)
528 -- to be used to obtain full RM compliant support.
530 Denorm_On_Target : Boolean := False;
531 -- Set to False on targets that do not reliably support denormals
533 Machine_Rounds_On_Target : Boolean := True;
534 -- Set to False for targets where S'Machine_Rounds is False
536 Machine_Overflows_On_Target : Boolean := False;
537 -- Set to True for targets where S'Machine_Overflows is True
539 Signed_Zeros_On_Target : Boolean := True;
540 -- Set to False on targets that do not reliably support signed zeros
542 -------------------------------------------
543 -- Boolean-Valued Fixed-Point Attributes --
544 -------------------------------------------
546 Fractional_Fixed_Ops_On_Target : Boolean := False;
547 -- Set to True for targets that support fixed-by-fixed multiplication
548 -- and division for fixed-point types with a small value equal to
549 -- 2 ** (-(T'Object_Size - 1)) and whose values have an absolute
550 -- value less than 1.0.
552 -----------------
553 -- Subprograms --
554 -----------------
556 -- These subprograms are used to initialize the target parameter values
557 -- from the system.ads file. Note that this is only done once, so if more
558 -- than one call is made to either routine, the second and subsequent
559 -- calls are ignored. It also reads restriction pragmas from system.ads
560 -- and records them, though as further detailed below, the caller has some
561 -- control over the handling of No_Dependence restrictions.
563 type Make_Id_Type is access function (Str : Text_Buffer) return Node_Id;
564 -- Parameter type for Get_Target_Parameters for function that creates an
565 -- identifier node with Sloc value System_Location and given string as the
566 -- Chars value.
568 type Make_SC_Type is access function (Pre, Sel : Node_Id) return Node_Id;
569 -- Parameter type for Get_Target_Parameters for function that creates a
570 -- selected component with Sloc value System_Location and given Prefix
571 -- (Pre) and Selector (Sel) values.
573 type Set_NOD_Type is access procedure (Unit : Node_Id);
574 -- Parameter type for Get_Target_Parameters that records a Restriction
575 -- No_Dependence for the given unit (identifier or selected component).
577 type Set_NSA_Type is access procedure (Asp : Name_Id; OK : out Boolean);
578 -- Parameter type for Get_Target_Parameters that records a Restriction
579 -- No_Specification_Of_Aspect. Asp is the aspect name. OK is set True
580 -- if this is an OK aspect name, and False if it is not an aspect name.
582 type Set_NUA_Type is access procedure (Attr : Name_Id; OK : out Boolean);
583 -- Parameter type for Get_Target_Parameters that records a Restriction
584 -- No_Use_Of_Attribute. Attr is the attribute name. OK is set True if
585 -- this is an OK attribute name, and False if it is not an attribute name.
587 type Set_NUP_Type is access procedure (Prag : Name_Id; OK : out Boolean);
588 -- Parameter type for Get_Target_Parameters that records a Restriction
589 -- No_Use_Of_Pragma. Prag is the pragma name. OK is set True if this is
590 -- an OK pragma name, and False if it is not a recognized pragma name.
592 procedure Get_Target_Parameters
593 (System_Text : Source_Buffer_Ptr;
594 Source_First : Source_Ptr;
595 Source_Last : Source_Ptr;
596 Make_Id : Make_Id_Type := null;
597 Make_SC : Make_SC_Type := null;
598 Set_NOD : Set_NOD_Type := null;
599 Set_NSA : Set_NSA_Type := null;
600 Set_NUA : Set_NUA_Type := null;
601 Set_NUP : Set_NUP_Type := null);
602 -- Called at the start of execution to obtain target parameters from the
603 -- source of package System. The parameters provide the source text to be
604 -- scanned (in System_Text (Source_First .. Source_Last)). If the three
605 -- subprograms Make_Id, Make_SC, and Set_NOD are left at their default
606 -- value of null, Get_Target_Parameters will ignore pragma Restrictions
607 -- (No_Dependence) lines; otherwise it will use these three subprograms to
608 -- record them. Similarly, if Set_NUP is left at its default value of null,
609 -- then any occurrences of pragma Restrictions (No_Use_Of_Pragma => XXX)
610 -- will be ignored; otherwise it will use this procedure to record the
611 -- pragma. Similarly for the NSA and NUA cases.
613 procedure Get_Target_Parameters
614 (Make_Id : Make_Id_Type := null;
615 Make_SC : Make_SC_Type := null;
616 Set_NOD : Set_NOD_Type := null;
617 Set_NSA : Set_NSA_Type := null;
618 Set_NUA : Set_NUA_Type := null;
619 Set_NUP : Set_NUP_Type := null);
620 -- This version reads in system.ads using Osint. The idea is that the
621 -- caller uses the first version if they have to read system.ads anyway
622 -- (e.g. the compiler) and uses this simpler interface if system.ads is
623 -- not otherwise needed.
625 end Targparm;