gcc/ada/validsw.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                              V A L I D S W                               --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --                            $Revision: 1.1 $
  10 --                                                                          --
  11 --             Copyright (C) 2001 Free Software Foundation, Inc.            --
  12 --                                                                          --
  13 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  14 -- terms of the  GNU General Public License as published  by the Free Soft- --
  15 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  16 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  17 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  18 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  19 -- for  more details.  You should have  received  a copy of the GNU General --
  20 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  21 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  22 -- MA 02111-1307, USA.                                                      --
  23 --                                                                          --
  24 -- GNAT was originally developed  by the GNAT team at  New York University. --
  25 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  26 --                                                                          --
  27 ------------------------------------------------------------------------------
  28
  29 --  This unit contains the routines used to handle setting of validity
  30 --  checking options.
  31
  32 package Validsw is
  33
  34    -----------------------------
  35    -- Validity Check Switches --
  36    -----------------------------
  37
  38    --  The following flags determine the specific set of validity checks
  39    --  to be made if validity checking is active (Validity_Checks_On = True)
  40
  41    --  See GNAT users guide for an exact description of each option. The letter
  42    --  given in the comment is the letter used in the -gnatV compiler switch
  43    --  or in the argument of a Validity_Checks pragma to activate the option.
  44    --  The corresponding upper case letter deactivates the option.
  45
  46    Validity_Check_Copies : Boolean := False;
  47    --  Controls the validity checking of copies. If this switch is set to
  48    --  true using -gnatVc, or a 'c' in the argument of a Validity_Checks
  49    --  pragma, then the right side of assignments and also initializing
  50    --  expressions in object declarations are checked for validity.
  51
  52    Validity_Check_Default : Boolean := True;
  53    --  Controls default (reference manual) validity checking. If this switch
  54    --  is set to True using -gnatVd or a 'd' in the argument of a Validity_
  55    --  Checks pragma then left side subscripts and case statement arguments
  56    --  are checked for validity. This switch is also set by default if no
  57    --  -gnatV switch is used and no Validity_Checks pragma is processed.
  58
  59    Validity_Check_Floating_Point : Boolean := False;
  60    --  Normally validity checking applies only to discrete values (integer
  61    --  and enumeration types). If this switch is set to True using -gnatVf
  62    --  or an 'f' in the argument of a Validity_Checks pragma, then floating-
  63    --  point values are also checked. The context in which such checks
  64    --  occur depends on other flags, e.g. if Validity_Check_Copies is also
  65    --  set then floating-point values on the right side of an assignment
  66    --  will be validity checked.
  67
  68    Validity_Check_In_Out_Params : Boolean := False;
  69    --  Controls the validity checking of IN OUT parameters. If this switch
  70    --  is set to True using -gnatVm or a 'm' in the argument of a pragma
  71    --  Validity_Checks, then the initial value of all IN OUT parameters
  72    --  will be checked at the point of call of a procecure. Note that the
  73    --  character 'm' here stands for modified (parameters).
  74
  75    Validity_Check_In_Params : Boolean := False;
  76    --  Controls the validity checking of IN parameters. If this switch is
  77    --  set to True using -gnatVm or an 'i' in the argument of a pragma
  78    --  Validity_Checks, then the initial value of all IN parameters
  79    --  will be checked at the point of call of a procecure or function.
  80
  81    Validity_Check_Operands : Boolean := False;
  82    --  Controls validity checking of operands. If this switch is set to
  83    --  True using -gnatVo or an 'o' in the argument of a Validity_Checks
  84    --  pragma, then operands of all predefined operators and attributes
  85    --  will be validity checked.
  86
  87    Validity_Check_Returns : Boolean := False;
  88    --  Controls validity checking of returned values. If this switch is set
  89    --  to True using -gnatVr, or an 'r' in the argument of a Validity_Checks
  90    --  pragma, then the expression in a RETURN statement is validity checked.
  91
  92    Validity_Check_Subscripts : Boolean := False;
  93    --  Controls validity checking of subscripts. If this switch is set to
  94    --  True using -gnatVs, or an 's' in the argument of a Validity_Checks
  95    --  pragma, then all subscripts are checked for validity. Note that left
  96    --  side subscript checking is controlled also by Validity_Check_Default.
  97    --  If Validity_Check_Subscripts is True, then all subscripts are checked,
  98    --  otherwise if Validity_Check_Default is True, then left side subscripts
  99    --  are checked, otherwise no subscripts are checked.
 100
 101    Validity_Check_Tests : Boolean := False;
 102    --  Controls validity checking of tests that occur in conditions (i.e. the
 103    --  tests in IF, WHILE, and EXIT statements, and in entry guards). If this
 104    --  switch is set to True using -gnatVt, or a 't' in the argument of a
 105    --  Validity_Checks pragma, then all such conditions are validity checked.
 106
 107    -----------------
 108    -- Subprograms --
 109    -----------------
 110
 111    procedure Set_Default_Validity_Check_Options;
 112    --  This procedure is called to set the default validity checking options
 113    --  that apply if no Validity_Check switches or pragma is given.
 114
 115    procedure Set_Validity_Check_Options
 116      (Options  : String;
 117       OK       : out Boolean;
 118       Err_Col  : out Natural);
 119    --  This procedure is called to set the validity check options that
 120    --  correspond to the characters in the given Options string. If
 121    --  all options are valid, then Set_Default_Validity_Check_Options
 122    --  is first called to set the defaults, and then the options in the
 123    --  given string are set in an additive manner. If any invalid character
 124    --  is found, then OK is False on exit, and Err_Col is the index in
 125    --  in options of the bad character. If all options are valid, then
 126    --  OK is True on return, and Err_Col is set to options'Last + 1.
 127
 128    procedure Set_Validity_Check_Options (Options : String);
 129    --  Like the above procedure, except that the call is simply ignored if
 130    --  there are any error conditions, this is for example appopriate for
 131    --  calls where the string is known to be valid, e.g. because it was
 132    --  obtained by Save_Validity_Check_Options.
 133
 134    procedure Reset_Validity_Check_Options;
 135    --  Sets all validity check options to off
 136
 137    subtype Validity_Check_Options is String (1 .. 16);
 138    --  Long enough string to hold all options from Save call below
 139
 140    procedure Save_Validity_Check_Options
 141      (Options : out Validity_Check_Options);
 142    --  Sets Options to represent current selection of options. This
 143    --  set can be restored by first calling Reset_Validity_Check_Options,
 144    --  and then calling Set_Validity_Check_Options with the Options string.
 145
 146 end Validsw;