-- --
-- S p e c --
-- --
--- Copyright (C) 1999-2004 Free Software Foundation, Inc. --
+-- Copyright (C) 1999-2007, 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- --
-- 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 COPYING. If not, write --
--- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
--- MA 02111-1307, USA. --
+-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
+-- Boston, MA 02110-1301, USA. --
+-- --
+-- As a special exception, if other files instantiate generics from this --
+-- unit, or you link this unit with other files to produce an executable, --
+-- this unit does not by itself cause the resulting executable to be --
+-- covered by the GNU General Public License. This exception does not --
+-- however invalidate any other reasons why the executable file might be --
+-- covered by the GNU Public License. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- computed and set in the ali file. This partially negates points 1 and 2
-- above although just parsing is quick and does not impact debugging much.
--- The parameters acquired by this routine from system.ads fall into three
+-- The parameters acquired by this routine from system.ads fall into four
-- categories:
-- 1. Configuration pragmas, that must appear at the start of the file.
-- line may be ommitted for a version of system.ads to be used with
-- the full Ada 95 run time.
+-- 4. Other characterisitics of package System. At the current time the
+-- only item in this category is whether type Address is private.
+
with Rident; use Rident;
+with Namet; use Namet;
with Types; use Types;
package Targparm is
-- If a pragma Polling (On) appears, then the flag Opt.Polling_Required
-- is set to True.
+ -- If a pragma Detect_Blocking appears, then the flag Opt.Detect_Blocking
+ -- is set to True.
+
-- if a pragma Suppress_Exception_Locations appears, then the flag
-- Opt.Exception_Locations_Suppressed is set to True.
- -- The only other pragma allowed is a pragma Restrictions that gives the
- -- simple name of a restriction for which partition consistency is always
- -- required (see definition of Rident.Restriction_Info).
+ -- If a pragma Profile with a valid profile argument appears, then
+ -- the appropriate restrictions and policy flags are set.
+
+ -- The only other pragma allowed is a pragma Restrictions that specifies
+ -- a restriction that will be imposed on all units in the partition. Note
+ -- that in this context, only one restriction can be specified in a single
+ -- pragma, and the pragma must appear on its own on a single source line.
- Restrictions_On_Target : Restrictions_Info;
+ -- If package System contains exactly the line "type Address is private;"
+ -- then the flag Opt.Address_Is_Private is set True, otherwise this flag
+ -- is set False.
+
+ Restrictions_On_Target : Restrictions_Info := No_Restrictions;
-- Records restrictions specified by system.ads. Only the Set and Value
-- members are modified. The Violated and Count fields are never modified.
+ -- Note that entries can be set either by a pragma Restrictions or by
+ -- a pragma Profile.
-------------------
-- Run Time Name --
-- The name should contain only letters A-Z, digits 1-9, spaces,
-- and underscores.
+ --------------------------
+ -- Executable Extension --
+ --------------------------
+
+ Executable_Extension_On_Target : Name_Id := No_Name;
+ -- Executable extension on the target. This name is useful for setting
+ -- the executable extension in a dynamic way, e.g. depending on the
+ -- run time used, rather than using a configure-time macro as done by
+ -- Get_Target_Executable_Suffix. If not set (No_Name), instead use
+ -- System.OS_Lib.Get_Target_Executable_Suffix.
+
-----------------------
-- Target Parameters --
-----------------------
-- Get_Target_Parameters routine which reads the values from a provided
-- text buffer containing the source of the system package.
+ -- The default values here are used if no value is found in system.ads.
+ -- This should normally happen if the special version of system.ads used
+ -- by the compiler itself is in use or if the value is only relevant to
+ -- a particular target (e.g. OpenVMS, AAMP). The default values are
+ -- suitable for use in normal environments. This approach allows the
+ -- possibility of new versions of the compiler (possibly with new system
+ -- parameters added) being used to compile older versions of the compiler
+ -- sources, as well as avoiding duplicating values in all system-*.ads
+ -- files for flags that are used on a few platforms only.
+
----------------------------
-- Special Target Control --
----------------------------
-- The great majority of GNAT ports are based on GCC. The switches in
- -- This section indicate the use of some non-standard target back end.
+ -- This section indicate the use of some non-standard target back end
+ -- or other special targetting requirements.
+
+ AAMP_On_Target : Boolean := False;
+ -- Set to True if target is AAMP
- AAMP_On_Target : Boolean;
- -- Set to True if target is AAMP.
+ OpenVMS_On_Target : Boolean := False;
+ -- Set to True if target is OpenVMS
+
+ type Virtual_Machine_Kind is (No_VM, JVM_Target, CLI_Target);
+ VM_Target : Virtual_Machine_Kind := No_VM;
+ -- Kind of virtual machine targetted
-------------------------------
-- Backend Arithmetic Checks --
-- end will generate the required checks (or that the checks are
-- automatically performed by the hardware in an appropriate form).
- Backend_Divide_Checks_On_Target : Boolean;
+ Backend_Divide_Checks_On_Target : Boolean := False;
-- Set True if the back end generates divide checks, or if the hardware
-- checks automatically. Set False if the front end must generate the
-- required tests using explicit expanded code.
- Backend_Overflow_Checks_On_Target : Boolean;
+ Backend_Overflow_Checks_On_Target : Boolean := False;
-- Set True if the back end generates arithmetic overflow checks, or if
-- the hardware checks automatically. Set False if the front end must
-- generate the required tests using explicit expanded code.
-- Controlling the selection of methods
- -- The Front-End Longjmp/Setjmp approach is always available in
- -- all implementations. If it is not the default method, then it
- -- may be explicitly specified by the use of -gnatL. Note however
- -- that there is a requirement that all Ada units in a partition
- -- be compiled with this overriding option if it is not the default.
-
- -- On some, but not all, implementations of GNAT, one of the two
- -- ZCX approaches (but not both) is implemented. If this is the
- -- case, and ZCX is not the default mechanism, then ZCX handling
- -- (front-end or back-end according to the implementation) may be
- -- specified by use of the -gnatZ switch. Again, this switch must
- -- be used to compile all Ada units in a partition. The use of
- -- the -gnatZ switch will cause termination with a fatal error.
-
- -- Finally the debug option -gnatdX can be used to force the
- -- compiler to operate in front-end ZCX exception mode and force
- -- the front end to generate exception tables. This is only useful
- -- for debugging purposes for implementations which do not provide
- -- the possibility of front-end ZCX mode. The resulting object file
- -- is unusable, but this debug switch may still be useful (e.g. in
- -- conjunction with -gnatG) for front-end debugging purposes.
+ -- On most implementations, back-end zero-cost exceptions are used.
+ -- Otherwise, Front-End Longjmp/Setjmp approach is used.
+ -- Note that there is a requirement that all Ada units in a partition
+ -- be compiled with the same exception model.
-- Control of Available Methods and Defaults
- -- The following switches specify which of the two ZCX methods
- -- (if any) is available in an implementation, and which method
- -- is the default method.
+ -- The following switches specify whether ZCX is available, and
+ -- whether it is enabled by default.
- ZCX_By_Default_On_Target : Boolean;
+ ZCX_By_Default_On_Target : Boolean := False;
-- Indicates if zero cost exceptions are active by default. If this
-- variable is False, then the only possible exception method is the
-- front-end setjmp/longjmp approach, and this is the default. If
- -- this variable is True, then one of the following two flags must
- -- be True, and represents the method to be used by default.
-
- GCC_ZCX_Support_On_Target : Boolean;
- -- Indicates that when ZCX is active, the mechanism to be used is the
- -- back-end ZCX exception approach. If this variable is set to True,
- -- then Front_End_ZCX_Support_On_Target must be False.
+ -- this variable is True, then GCC ZCX is used.
- Front_End_ZCX_Support_On_Target : Boolean;
- -- Indicates that when ZCX is active, the mechanism to be used is the
- -- front-end ZCX exception approach. If this variable is set to True,
- -- then GCC_ZCX_Support_On_Target must be False.
+ GCC_ZCX_Support_On_Target : Boolean := False;
+ -- Indicates that the target supports GCC Exceptions
- --------------------------------
- -- Configurable Run-Time Mode --
- --------------------------------
+ ------------------------------------
+ -- Run-Time Library Configuration --
+ ------------------------------------
-- In configurable run-time mode, the system run-time may not support
-- the full Ada language. The effect of setting this switch is to let
-- misconfigured) if run-time library units or entities within units are
-- not present in the run-time.
- Configurable_Run_Time_On_Target : Boolean;
+ Configurable_Run_Time_On_Target : Boolean := False;
-- Indicates that the system.ads file is for a configurable run-time
--
-- This has some specific effects as follows
-- The variable __gnat_exit_status is generated within the binder file
-- instead of being imported from the run-time library.
- Suppress_Standard_Library_On_Target : Boolean;
+ Suppress_Standard_Library_On_Target : Boolean := False;
-- If this flag is True, then the standard library is not included by
-- default in the executable (see unit System.Standard_Library in file
-- s-stalib.ads for details of what this includes). This is for example
-- with the exception of the priority of the environment task, which
-- is needed by the Ravenscar run-time.
--
- -- The generation of exception tables is suppressed for front end
- -- ZCX exception handling (since we assume no exception handling).
- --
-- The calls to __gnat_initialize and __gnat_finalize are omitted
--
-- All finalization and initialization (controlled types) is omitted
--
-- The routine __gnat_handler_installed is not imported
+ Preallocated_Stacks_On_Target : Boolean := False;
+ -- If this flag is True, then the expander preallocates all task stacks
+ -- at compile time. If the flag is False, then task stacks are not pre-
+ -- allocated, and task stack allocation is the responsibility of the
+ -- run-time (which typically delegates the task to the underlying
+ -- operating system environment).
+
---------------------
-- Duration Format --
---------------------
-- and small of 10**(-9) (i.e. it is a count in nanoseconds. This flag
-- allows that standard format to be modified.
- Duration_32_Bits_On_Target : Boolean;
+ Duration_32_Bits_On_Target : Boolean := False;
-- If True, then Duration is represented in 32 bits and the delta and
-- small values are set to 20.0*(10**(-3)) (i.e. it is a count in units
-- of 20 milliseconds.
-- used at the source level, and the corresponding flag is false, then an
-- error message will be issued saying the feature is not supported.
- Support_64_Bit_Divides_On_Target : Boolean;
+ Support_64_Bit_Divides_On_Target : Boolean := True;
-- If True, the back end supports 64-bit divide operations. If False, then
-- the source program may not contain 64-bit divide operations. This is
-- specifically useful in the zero foot-print case, where the issue is
-- no run-time support is required. It should always be set True if the
-- necessary run-time support is present.
- Support_Aggregates_On_Target : Boolean;
+ Support_Aggregates_On_Target : Boolean := True;
-- In the general case, the use of aggregates may generate calls
-- to run-time routines in the C library, including memset, memcpy,
-- memmove, and bcopy. This flag is set to True if these routines
-- are available. If any of these routines is not available, then
-- this flag is False, and the use of aggregates is not permitted.
- Support_Composite_Assign_On_Target : Boolean;
+ Support_Composite_Assign_On_Target : Boolean := True;
-- The assignment of composite objects other than small records and
-- arrays whose size is 64-bits or less and is set by an explicit
-- size clause may generate calls to memcpy, memmove, and bcopy.
-- is set to True. If any of these routines is not available, then
-- the flag is set False, and composite assignments are not allowed.
- Support_Composite_Compare_On_Target : Boolean;
+ Support_Composite_Compare_On_Target : Boolean := True;
-- If this flag is True, then the back end supports bit-wise comparison
-- of composite objects for equality, either generating inline code or
-- calling appropriate (and available) run-time routines. If this flag
-- is False, then the back end does not provide this support, and the
-- front end uses component by component comparison for composites.
- Support_Long_Shifts_On_Target : Boolean;
+ Support_Long_Shifts_On_Target : Boolean := True;
-- If True, the back end supports 64-bit shift operations. If False, then
-- the source program may not contain explicit 64-bit shifts. In addition,
-- the code generated for packed arrays will avoid the use of long shifts.
-- default on systems that lack complete support for
-- probing.
- Stack_Check_Probes_On_Target : Boolean;
+ Stack_Check_Probes_On_Target : Boolean := False;
-- Indicates if stack check probes are used, as opposed to the standard
-- target independent comparison method.
- Stack_Check_Default_On_Target : Boolean;
+ Stack_Check_Default_On_Target : Boolean := False;
-- Indicates if stack checking is on by default
----------------------------
-- command line arguments (VxWorks and AAMP). Note that support of
-- command line arguments is not required on such targets (RM A.15(13)).
- Command_Line_Args_On_Target : Boolean;
+ Command_Line_Args_On_Target : Boolean := True;
-- Set False if no command line arguments on target. Note that if this
-- is False in with Configurable_Run_Time_On_Target set to True, then
-- this causes suppression of generation of the argv/argc variables
-- Similarly, most ports support the use of an exit status, but AAMP
-- is an exception (as allowed by RM A.15(18-20))
- Exit_Status_Supported_On_Target : Boolean;
+ Exit_Status_Supported_On_Target : Boolean := True;
-- Set False if returning of an exit status is not supported on target.
-- Note that if this False in with Configurable_Run_Time_On_Target
-- set to True, then this causes suppression of the gnat_exit_status
- -- variable used to recod the exit status.
+ -- variable used to record the exit status.
-----------------------
-- Main Program Name --
-- name (just the name of the child if the main program is a child unit).
-- In either case, this value can be overridden using -M name.
- Use_Ada_Main_Program_Name_On_Target : Boolean;
+ Use_Ada_Main_Program_Name_On_Target : Boolean := False;
-- Set True to use the Ada main program name as the main name
----------------------------------------------
-- the partition. We probably should add such consistency checks in future,
-- but for now we don't do this.
- Denorm_On_Target : Boolean;
- -- Set to False on targets that do not reliably support denormals.
- -- Reliably here means for all settings of the relevant -m flag, so
- -- for example, this is False on the Alpha where denormals are not
- -- supported unless -mieee is used.
+ -- Note: the compiler itself does not use floating-point, so the
+ -- settings of the defaults here are not really relevant.
+
+ -- Note: in some cases, proper support of some of these floating point
+ -- features may require a specific switch (e.g. -mieee on the Alpha)
+ -- to be used to obtain full RM compliant support.
+
+ Denorm_On_Target : Boolean := False;
+ -- Set to False on targets that do not reliably support denormals
- Machine_Rounds_On_Target : Boolean;
+ Machine_Rounds_On_Target : Boolean := True;
-- Set to False for targets where S'Machine_Rounds is False
- Machine_Overflows_On_Target : Boolean;
+ Machine_Overflows_On_Target : Boolean := False;
-- Set to True for targets where S'Machine_Overflows is True
- Signed_Zeros_On_Target : Boolean;
- -- Set to False on targets that do not reliably support signed zeros.
-
- OpenVMS_On_Target : Boolean;
- -- Set to True if target is OpenVMS.
+ Signed_Zeros_On_Target : Boolean := True;
+ -- Set to False on targets that do not reliably support signed zeros
-------------------------------------------
-- Boolean-Valued Fixed-Point Attributes --
-------------------------------------------
- Fractional_Fixed_Ops_On_Target : Boolean;
+ Fractional_Fixed_Ops_On_Target : Boolean := False;
-- Set to True for targets that support fixed-by-fixed multiplication
-- and division for fixed-point types with a small value equal to
-- 2 ** (-(T'Object_Size - 1)) and whose values have an absolute
-- value less than 1.0.
- --------------------------------------------------------------
- -- Handling of Unconstrained Values Returned from Functions --
- --------------------------------------------------------------
-
- -- Functions that return variable length objects, notably unconstrained
- -- arrays are a special case, because there is no simple obvious way of
- -- implementing this feature. Furthermore, this capability is not present
- -- in C++ or C, so typically the system ABI does not handle this case.
-
- -- GNAT uses two different approaches
-
- -- The Secondary Stack
-
- -- The secondary stack is a special storage pool that is used for
- -- this purpose. The called function places the result on the
- -- secondary stack, and the caller uses or copies the value from
- -- the secondary stack, and pops the secondary stack after the
- -- value is consumed. The secondary stack is outside the system
- -- ABI, and the important point is that although generally it is
- -- handled in a stack like manner corresponding to the subprogram
- -- call structure, a return from a function does NOT pop the stack.
-
- -- DSP (Depressed Stack Pointer)
-
- -- Some targets permit the implementation of a function call/return
- -- protocol in which the function does not pop the main stack pointer
- -- on return, but rather returns with the stack pointer depressed.
- -- This is not generally permitted by any ABI, but for at least some
- -- targets, the implementation of alloca provides a model for this
- -- approach. If return-with-DSP is implemented, then functions that
- -- return variable length objects do it by returning with the stack
- -- pointer depressed, and the returned object is a pointer to the
- -- area within the stack frame of the called procedure that contains
- -- the returned value. The caller must then pop the main stack when
- -- this value is consumed.
-
- Functions_Return_By_DSP_On_Target : Boolean;
- -- Set to True if target permits functions to return with using the
- -- DSP (depressed stack pointer) approach.
-
-----------------
-- Data Layout --
-----------------
-- parameter Backend_Layout is set to False, then the front end must
-- perform all data layout. For further details see the package Layout.
- Frontend_Layout_On_Target : Boolean;
+ Frontend_Layout_On_Target : Boolean := False;
-- Set True if front end does layout
-----------------
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