GNAT Reference Manual

GNAT Reference Manual

GNAT Reference Manual

GNAT, The GNU Ada Development Environment
GCC version 4.9.4

AdaCore

• About This Guide
• Implementation Defined Pragmas
• Implementation Defined Aspects
• Implementation Defined Attributes
• Standard and Implementation Defined Restrictions
• Implementation Advice
• Implementation Defined Characteristics
• Intrinsic Subprograms
• Representation Clauses and Pragmas
• Standard Library Routines
• The Implementation of Standard I/O
• The GNAT Library
• Interfacing to Other Languages
• Specialized Needs Annexes
• Implementation of Specific Ada Features
• Implementation of Ada 2012 Features
• Obsolescent Features
• GNU Free Documentation License
• Index

--- The Detailed Node Listing ---

About This Guide

• What This Reference Manual Contains
• Related Information

Implementation Defined Pragmas

• Pragma Abort_Defer
• Pragma Abstract_State
• Pragma Ada_83
• Pragma Ada_95
• Pragma Ada_05
• Pragma Ada_2005
• Pragma Ada_12
• Pragma Ada_2012
• Pragma Allow_Integer_Address
• Pragma Annotate
• Pragma Assert
• Pragma Assert_And_Cut
• Pragma Assertion_Policy
• Pragma Assume
• Pragma Assume_No_Invalid_Values
• Pragma Attribute_Definition
• Pragma Ast_Entry
• Pragma C_Pass_By_Copy
• Pragma Check
• Pragma Check_Float_Overflow
• Pragma Check_Name
• Pragma Check_Policy
• Pragma CIL_Constructor
• Pragma Comment
• Pragma Common_Object
• Pragma Compile_Time_Error
• Pragma Compile_Time_Warning
• Pragma Compiler_Unit
• Pragma Compiler_Unit_Warning
• Pragma Complete_Representation
• Pragma Complex_Representation
• Pragma Component_Alignment
• Pragma Contract_Cases
• Pragma Convention_Identifier
• Pragma CPP_Class
• Pragma CPP_Constructor
• Pragma CPP_Virtual
• Pragma CPP_Vtable
• Pragma CPU
• Pragma Debug
• Pragma Debug_Policy
• Pragma Default_Storage_Pool
• Pragma Depends
• Pragma Detect_Blocking
• Pragma Disable_Atomic_Synchronization
• Pragma Dispatching_Domain
• Pragma Elaboration_Checks
• Pragma Eliminate
• Pragma Enable_Atomic_Synchronization
• Pragma Export_Exception
• Pragma Export_Function
• Pragma Export_Object
• Pragma Export_Procedure
• Pragma Export_Value
• Pragma Export_Valued_Procedure
• Pragma Extend_System
• Pragma Extensions_Allowed
• Pragma External
• Pragma External_Name_Casing
• Pragma Fast_Math
• Pragma Favor_Top_Level
• Pragma Finalize_Storage_Only
• Pragma Float_Representation
• Pragma Global
• Pragma Ident
• Pragma Implementation_Defined
• Pragma Implemented
• Pragma Implicit_Packing
• Pragma Import_Exception
• Pragma Import_Function
• Pragma Import_Object
• Pragma Import_Procedure
• Pragma Import_Valued_Procedure
• Pragma Independent
• Pragma Independent_Components
• Pragma Initial_Condition
• Pragma Initialize_Scalars
• Pragma Initializes
• Pragma Inline_Always
• Pragma Inline_Generic
• Pragma Interface
• Pragma Interface_Name
• Pragma Interrupt_Handler
• Pragma Interrupt_State
• Pragma Invariant
• Pragma Java_Constructor
• Pragma Java_Interface
• Pragma Keep_Names
• Pragma License
• Pragma Link_With
• Pragma Linker_Alias
• Pragma Linker_Constructor
• Pragma Linker_Destructor
• Pragma Linker_Section
• Pragma Long_Float
• Pragma Loop_Invariant
• Pragma Loop_Optimize
• Pragma Loop_Variant
• Pragma Machine_Attribute
• Pragma Main
• Pragma Main_Storage
• Pragma No_Body
• Pragma No_Inline
• Pragma No_Return
• Pragma No_Run_Time
• Pragma No_Strict_Aliasing
• Pragma Normalize_Scalars
• Pragma Obsolescent
• Pragma Optimize_Alignment
• Pragma Ordered
• Pragma Overflow_Mode
• Pragma Overriding_Renamings
• Pragma Partition_Elaboration_Policy
• Pragma Passive
• Pragma Persistent_BSS
• Pragma Polling
• Pragma Post
• Pragma Postcondition
• Pragma Post_Class
• Pragma Pre
• Pragma Precondition
• Pragma Predicate
• Pragma Preelaborable_Initialization
• Pragma Preelaborate_05
• Pragma Pre_Class
• Pragma Priority_Specific_Dispatching
• Pragma Profile
• Pragma Profile_Warnings
• Pragma Propagate_Exceptions
• Pragma Provide_Shift_Operators
• Pragma Psect_Object
• Pragma Pure_05
• Pragma Pure_12
• Pragma Pure_Function
• Pragma Ravenscar
• Pragma Refined_State
• Pragma Relative_Deadline
• Pragma Remote_Access_Type
• Pragma Restricted_Run_Time
• Pragma Restriction_Warnings
• Pragma Reviewable
• Pragma Share_Generic
• Pragma Shared
• Pragma Short_Circuit_And_Or
• Pragma Short_Descriptors
• Pragma Simple_Storage_Pool_Type
• Pragma Source_File_Name
• Pragma Source_File_Name_Project
• Pragma Source_Reference
• Pragma SPARK_Mode
• Pragma Static_Elaboration_Desired
• Pragma Stream_Convert
• Pragma Style_Checks
• Pragma Subtitle
• Pragma Suppress
• Pragma Suppress_All
• Pragma Suppress_Debug_Info
• Pragma Suppress_Exception_Locations
• Pragma Suppress_Initialization
• Pragma Task_Info
• Pragma Task_Name
• Pragma Task_Storage
• Pragma Test_Case
• Pragma Thread_Local_Storage
• Pragma Time_Slice
• Pragma Title
• Pragma Type_Invariant
• Pragma Type_Invariant_Class
• Pragma Unchecked_Union
• Pragma Unimplemented_Unit
• Pragma Universal_Aliasing
• Pragma Universal_Data
• Pragma Unmodified
• Pragma Unreferenced
• Pragma Unreferenced_Objects
• Pragma Unreserve_All_Interrupts
• Pragma Unsuppress
• Pragma Use_VADS_Size
• Pragma Validity_Checks
• Pragma Volatile
• Pragma Warning_As_Error
• Pragma Warnings
• Pragma Weak_External
• Pragma Wide_Character_Encoding

Implementation Defined Aspects

• Aspect Abstract_State
• Aspect Contract_Cases
• Aspect Depends
• Aspect Dimension
• Aspect Dimension_System
• Aspect Favor_Top_Level
• Aspect Global
• Aspect Initial_Condition
• Aspect Initializes
• Aspect Inline_Always
• Aspect Invariant
• Aspect Linker_Section
• Aspect Object_Size
• Aspect Persistent_BSS
• Aspect Predicate
• Aspect Preelaborate_05
• Aspect Pure_05
• Aspect Pure_12
• Aspect Pure_Function
• Aspect Refined_State
• Aspect Remote_Access_Type
• Aspect Scalar_Storage_Order
• Aspect Shared
• Aspect Simple_Storage_Pool
• Aspect Simple_Storage_Pool_Type
• Aspect SPARK_Mode
• Aspect Suppress_Debug_Info
• Aspect Test_Case
• Aspect Universal_Aliasing
• Aspect Universal_Data
• Aspect Unmodified
• Aspect Unreferenced
• Aspect Unreferenced_Objects
• Aspect Value_Size
• Aspect Warnings

Implementation Defined Attributes

• Attribute Abort_Signal
• Attribute Address_Size
• Attribute Asm_Input
• Attribute Asm_Output
• Attribute AST_Entry
• Attribute Bit
• Attribute Bit_Position
• Attribute Compiler_Version
• Attribute Code_Address
• Attribute Default_Bit_Order
• Attribute Descriptor_Size
• Attribute Elaborated
• Attribute Elab_Body
• Attribute Elab_Spec
• Attribute Elab_Subp_Body
• Attribute Emax
• Attribute Enabled
• Attribute Enum_Rep
• Attribute Enum_Val
• Attribute Epsilon
• Attribute Fixed_Value
• Attribute Has_Access_Values
• Attribute Has_Discriminants
• Attribute Img
• Attribute Integer_Value
• Attribute Invalid_Value
• Attribute Large
• Attribute Library_Level
• Attribute Loop_Entry
• Attribute Machine_Size
• Attribute Mantissa
• Attribute Max_Interrupt_Priority
• Attribute Max_Priority
• Attribute Maximum_Alignment
• Attribute Mechanism_Code
• Attribute Null_Parameter
• Attribute Object_Size
• Attribute Passed_By_Reference
• Attribute Pool_Address
• Attribute Range_Length
• Attribute Ref
• Attribute Restriction_Set
• Attribute Result
• Attribute Safe_Emax
• Attribute Safe_Large
• Attribute Scalar_Storage_Order
• Attribute Simple_Storage_Pool
• Attribute Small
• Attribute Storage_Unit
• Attribute Stub_Type
• Attribute System_Allocator_Alignment
• Attribute Target_Name
• Attribute Tick
• Attribute To_Address
• Attribute Type_Class
• Attribute UET_Address
• Attribute Unconstrained_Array
• Attribute Universal_Literal_String
• Attribute Unrestricted_Access
• Attribute Update
• Attribute Valid_Scalars
• Attribute VADS_Size
• Attribute Value_Size
• Attribute Wchar_T_Size
• Attribute Word_Size

Standard and Implementation Defined Restrictions

• Partition-Wide Restrictions
• Program Unit Level Restrictions

Partition-Wide Restrictions

• Immediate_Reclamation
• Max_Asynchronous_Select_Nesting
• Max_Entry_Queue_Length
• Max_Protected_Entries
• Max_Select_Alternatives
• Max_Storage_At_Blocking
• Max_Task_Entries
• Max_Tasks
• No_Abort_Statements
• No_Access_Parameter_Allocators
• No_Access_Subprograms
• No_Allocators
• No_Anonymous_Allocators
• No_Calendar
• No_Coextensions
• No_Default_Initialization
• No_Delay
• No_Dependence
• No_Direct_Boolean_Operators
• No_Dispatch
• No_Dispatching_Calls
• No_Dynamic_Attachment
• No_Dynamic_Priorities
• No_Entry_Calls_In_Elaboration_Code
• No_Enumeration_Maps
• No_Exception_Handlers
• No_Exception_Propagation
• No_Exception_Registration
• No_Exceptions
• No_Finalization
• No_Fixed_Point
• No_Floating_Point
• No_Implicit_Conditionals
• No_Implicit_Dynamic_Code
• No_Implicit_Heap_Allocations
• No_Implicit_Loops
• No_Initialize_Scalars
• No_IO
• No_Local_Allocators
• No_Local_Protected_Objects
• No_Local_Timing_Events
• No_Nested_Finalization
• No_Protected_Type_Allocators
• No_Protected_Types
• No_Recursion
• No_Reentrancy
• No_Relative_Delay
• No_Requeue_Statements
• No_Secondary_Stack
• No_Select_Statements
• No_Specific_Termination_Handlers
• No_Specification_of_Aspect
• No_Standard_Allocators_After_Elaboration
• No_Standard_Storage_Pools
• No_Stream_Optimizations
• No_Streams
• No_Task_Allocators
• No_Task_Attributes_Package
• No_Task_Hierarchy
• No_Task_Termination
• No_Tasking
• No_Terminate_Alternatives
• No_Unchecked_Access
• Simple_Barriers
• Static_Priorities
• Static_Storage_Size

Program Unit Level Restrictions

• No_Elaboration_Code
• No_Entry_Queue
• No_Implementation_Aspect_Specifications
• No_Implementation_Attributes
• No_Implementation_Identifiers
• No_Implementation_Pragmas
• No_Implementation_Restrictions
• No_Implementation_Units
• No_Implicit_Aliasing
• No_Obsolescent_Features
• No_Wide_Characters
• SPARK_05

The Implementation of Standard I/O

• Standard I/O Packages
• FORM Strings
• Direct_IO
• Sequential_IO
• Text_IO
• Wide_Text_IO
• Wide_Wide_Text_IO
• Stream_IO
• Text Translation
• Shared Files
• Filenames encoding
• Open Modes
• Operations on C Streams
• Interfacing to C Streams

The GNAT Library

• Ada.Characters.Latin_9 (a-chlat9.ads)
• Ada.Characters.Wide_Latin_1 (a-cwila1.ads)
• Ada.Characters.Wide_Latin_9 (a-cwila9.ads)
• Ada.Characters.Wide_Wide_Latin_1 (a-chzla1.ads)
• Ada.Characters.Wide_Wide_Latin_9 (a-chzla9.ads)
• Ada.Containers.Formal_Doubly_Linked_Lists (a-cfdlli.ads)
• Ada.Containers.Formal_Hashed_Maps (a-cfhama.ads)
• Ada.Containers.Formal_Hashed_Sets (a-cfhase.ads)
• Ada.Containers.Formal_Ordered_Maps (a-cforma.ads)
• Ada.Containers.Formal_Ordered_Sets (a-cforse.ads)
• Ada.Containers.Formal_Vectors (a-cofove.ads)
• Ada.Command_Line.Environment (a-colien.ads)
• Ada.Command_Line.Remove (a-colire.ads)
• Ada.Command_Line.Response_File (a-clrefi.ads)
• Ada.Direct_IO.C_Streams (a-diocst.ads)
• Ada.Exceptions.Is_Null_Occurrence (a-einuoc.ads)
• Ada.Exceptions.Last_Chance_Handler (a-elchha.ads)
• Ada.Exceptions.Traceback (a-exctra.ads)
• Ada.Sequential_IO.C_Streams (a-siocst.ads)
• Ada.Streams.Stream_IO.C_Streams (a-ssicst.ads)
• Ada.Strings.Unbounded.Text_IO (a-suteio.ads)
• Ada.Strings.Wide_Unbounded.Wide_Text_IO (a-swuwti.ads)
• Ada.Strings.Wide_Wide_Unbounded.Wide_Wide_Text_IO (a-szuzti.ads)
• Ada.Text_IO.C_Streams (a-tiocst.ads)
• Ada.Text_IO.Reset_Standard_Files (a-tirsfi.ads)
• Ada.Wide_Characters.Unicode (a-wichun.ads)
• Ada.Wide_Text_IO.C_Streams (a-wtcstr.ads)
• Ada.Wide_Text_IO.Reset_Standard_Files (a-wrstfi.ads)
• Ada.Wide_Wide_Characters.Unicode (a-zchuni.ads)
• Ada.Wide_Wide_Text_IO.C_Streams (a-ztcstr.ads)
• Ada.Wide_Wide_Text_IO.Reset_Standard_Files (a-zrstfi.ads)
• GNAT.Altivec (g-altive.ads)
• GNAT.Altivec.Conversions (g-altcon.ads)
• GNAT.Altivec.Vector_Operations (g-alveop.ads)
• GNAT.Altivec.Vector_Types (g-alvety.ads)
• GNAT.Altivec.Vector_Views (g-alvevi.ads)
• GNAT.Array_Split (g-arrspl.ads)
• GNAT.AWK (g-awk.ads)
• GNAT.Bounded_Buffers (g-boubuf.ads)
• GNAT.Bounded_Mailboxes (g-boumai.ads)
• GNAT.Bubble_Sort (g-bubsor.ads)
• GNAT.Bubble_Sort_A (g-busora.ads)
• GNAT.Bubble_Sort_G (g-busorg.ads)
• GNAT.Byte_Order_Mark (g-byorma.ads)
• GNAT.Byte_Swapping (g-bytswa.ads)
• GNAT.Calendar (g-calend.ads)
• GNAT.Calendar.Time_IO (g-catiio.ads)
• GNAT.Case_Util (g-casuti.ads)
• GNAT.CGI (g-cgi.ads)
• GNAT.CGI.Cookie (g-cgicoo.ads)
• GNAT.CGI.Debug (g-cgideb.ads)
• GNAT.Command_Line (g-comlin.ads)
• GNAT.Compiler_Version (g-comver.ads)
• GNAT.Ctrl_C (g-ctrl_c.ads)
• GNAT.CRC32 (g-crc32.ads)
• GNAT.Current_Exception (g-curexc.ads)
• GNAT.Debug_Pools (g-debpoo.ads)
• GNAT.Debug_Utilities (g-debuti.ads)
• GNAT.Decode_String (g-decstr.ads)
• GNAT.Decode_UTF8_String (g-deutst.ads)
• GNAT.Directory_Operations (g-dirope.ads)
• GNAT.Directory_Operations.Iteration (g-diopit.ads)
• GNAT.Dynamic_HTables (g-dynhta.ads)
• GNAT.Dynamic_Tables (g-dyntab.ads)
• GNAT.Encode_String (g-encstr.ads)
• GNAT.Encode_UTF8_String (g-enutst.ads)
• GNAT.Exception_Actions (g-excact.ads)
• GNAT.Exception_Traces (g-exctra.ads)
• GNAT.Exceptions (g-except.ads)
• GNAT.Expect (g-expect.ads)
• GNAT.Expect.TTY (g-exptty.ads)
• GNAT.Float_Control (g-flocon.ads)
• GNAT.Heap_Sort (g-heasor.ads)
• GNAT.Heap_Sort_A (g-hesora.ads)
• GNAT.Heap_Sort_G (g-hesorg.ads)
• GNAT.HTable (g-htable.ads)
• GNAT.IO (g-io.ads)
• GNAT.IO_Aux (g-io_aux.ads)
• GNAT.Lock_Files (g-locfil.ads)
• GNAT.MBBS_Discrete_Random (g-mbdira.ads)
• GNAT.MBBS_Float_Random (g-mbflra.ads)
• GNAT.MD5 (g-md5.ads)
• GNAT.Memory_Dump (g-memdum.ads)
• GNAT.Most_Recent_Exception (g-moreex.ads)
• GNAT.OS_Lib (g-os_lib.ads)
• GNAT.Perfect_Hash_Generators (g-pehage.ads)
• GNAT.Random_Numbers (g-rannum.ads)
• GNAT.Regexp (g-regexp.ads)
• GNAT.Registry (g-regist.ads)
• GNAT.Regpat (g-regpat.ads)
• GNAT.Secondary_Stack_Info (g-sestin.ads)
• GNAT.Semaphores (g-semaph.ads)
• GNAT.Serial_Communications (g-sercom.ads)
• GNAT.SHA1 (g-sha1.ads)
• GNAT.SHA224 (g-sha224.ads)
• GNAT.SHA256 (g-sha256.ads)
• GNAT.SHA384 (g-sha384.ads)
• GNAT.SHA512 (g-sha512.ads)
• GNAT.Signals (g-signal.ads)
• GNAT.Sockets (g-socket.ads)
• GNAT.Source_Info (g-souinf.ads)
• GNAT.Spelling_Checker (g-speche.ads)
• GNAT.Spelling_Checker_Generic (g-spchge.ads)
• GNAT.Spitbol.Patterns (g-spipat.ads)
• GNAT.Spitbol (g-spitbo.ads)
• GNAT.Spitbol.Table_Boolean (g-sptabo.ads)
• GNAT.Spitbol.Table_Integer (g-sptain.ads)
• GNAT.Spitbol.Table_VString (g-sptavs.ads)
• GNAT.SSE (g-sse.ads)
• GNAT.SSE.Vector_Types (g-ssvety.ads)
• GNAT.Strings (g-string.ads)
• GNAT.String_Split (g-strspl.ads)
• GNAT.Table (g-table.ads)
• GNAT.Task_Lock (g-tasloc.ads)
• GNAT.Threads (g-thread.ads)
• GNAT.Time_Stamp (g-timsta.ads)
• GNAT.Traceback (g-traceb.ads)
• GNAT.Traceback.Symbolic (g-trasym.ads)
• GNAT.UTF_32 (g-utf_32.ads)
• GNAT.UTF_32_Spelling_Checker (g-u3spch.ads)
• GNAT.Wide_Spelling_Checker (g-wispch.ads)
• GNAT.Wide_String_Split (g-wistsp.ads)
• GNAT.Wide_Wide_Spelling_Checker (g-zspche.ads)
• GNAT.Wide_Wide_String_Split (g-zistsp.ads)
• Interfaces.C.Extensions (i-cexten.ads)
• Interfaces.C.Streams (i-cstrea.ads)
• Interfaces.CPP (i-cpp.ads)
• Interfaces.Packed_Decimal (i-pacdec.ads)
• Interfaces.VxWorks (i-vxwork.ads)
• Interfaces.VxWorks.IO (i-vxwoio.ads)
• System.Address_Image (s-addima.ads)
• System.Assertions (s-assert.ads)
• System.Memory (s-memory.ads)
• System.Multiprocessors (s-multip.ads)
• System.Multiprocessors.Dispatching_Domains (s-mudido.ads)
• System.Partition_Interface (s-parint.ads)
• System.Pool_Global (s-pooglo.ads)
• System.Pool_Local (s-pooloc.ads)
• System.Restrictions (s-restri.ads)
• System.Rident (s-rident.ads)
• System.Strings.Stream_Ops (s-ststop.ads)
• System.Task_Info (s-tasinf.ads)
• System.Wch_Cnv (s-wchcnv.ads)
• System.Wch_Con (s-wchcon.ads)

Text_IO

• Text_IO Stream Pointer Positioning
• Text_IO Reading and Writing Non-Regular Files
• Get_Immediate
• Treating Text_IO Files as Streams
• Text_IO Extensions
• Text_IO Facilities for Unbounded Strings

Wide_Text_IO

• Wide_Text_IO Stream Pointer Positioning
• Wide_Text_IO Reading and Writing Non-Regular Files

Wide_Wide_Text_IO

• Wide_Wide_Text_IO Stream Pointer Positioning
• Wide_Wide_Text_IO Reading and Writing Non-Regular Files

Interfacing to Other Languages

• Interfacing to C
• Interfacing to C++
• Interfacing to COBOL
• Interfacing to Fortran
• Interfacing to non-GNAT Ada code

Specialized Needs Annexes

Implementation of Specific Ada Features

• Machine Code Insertions
• GNAT Implementation of Tasking
• GNAT Implementation of Shared Passive Packages
• Code Generation for Array Aggregates
• The Size of Discriminated Records with Default Discriminants
• Strict Conformance to the Ada Reference Manual

Implementation of Ada 2012 Features

Obsolescent Features

GNU Free Documentation License

Index