gcc/ada/frontend.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                             F R O N T E N D                              --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --                                                                          --
  10 --          Copyright (C) 1992-2002 Free Software Foundation, Inc.          --
  11 --                                                                          --
  12 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  13 -- terms of the  GNU General Public License as published  by the Free Soft- --
  14 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  15 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  16 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  17 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  18 -- for  more details.  You should have  received  a copy of the GNU General --
  19 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  20 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  21 -- MA 02111-1307, USA.                                                      --
  22 --                                                                          --
  23 -- GNAT was originally developed  by the GNAT team at  New York University. --
  24 -- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
  25 --                                                                          --
  26 ------------------------------------------------------------------------------
  27
  28 with Atree;    use Atree;
  29 with Checks;
  30 with CStand;
  31 with Debug;    use Debug;
  32 with Elists;
  33 with Exp_Ch11;
  34 with Exp_Dbug;
  35 with Fmap;
  36 with Fname.UF;
  37 with Hostparm; use Hostparm;
  38 with Inline;   use Inline;
  39 with Lib;      use Lib;
  40 with Lib.Load; use Lib.Load;
  41 with Live;     use Live;
  42 with Namet;    use Namet;
  43 with Nlists;   use Nlists;
  44 with Opt;      use Opt;
  45 with Osint;
  46 with Output;   use Output;
  47 with Par;
  48 with Rtsfind;
  49 with Sprint;
  50 with Scn;      use Scn;
  51 with Sem;      use Sem;
  52 with Sem_Ch8;  use Sem_Ch8;
  53 with Sem_Elab; use Sem_Elab;
  54 with Sem_Prag; use Sem_Prag;
  55 with Sem_Warn; use Sem_Warn;
  56 with Sinfo;    use Sinfo;
  57 with Sinput;   use Sinput;
  58 with Sinput.L; use Sinput.L;
  59 with Types;    use Types;
  60
  61 procedure Frontend is
  62       Pragmas : List_Id;
  63       Prag    : Node_Id;
  64
  65       Save_Style_Check : constant Boolean := Opt.Style_Check;
  66       --  Save style check mode so it can be restored later
  67
  68 begin
  69    --  Carry out package initializations. These are initializations which
  70    --  might logically be performed at elaboration time, were it not for
  71    --  the fact that we may be doing things more than once in the big loop
  72    --  over files. Like elaboration, the order in which these calls are
  73    --  made is in some cases important. For example, Lib cannot be
  74    --  initialized until Namet, since it uses names table entries.
  75
  76    Rtsfind.Initialize;
  77    Atree.Initialize;
  78    Nlists.Initialize;
  79    Elists.Initialize;
  80    Lib.Load.Initialize;
  81    Sem_Ch8.Initialize;
  82    Fname.UF.Initialize;
  83    Exp_Ch11.Initialize;
  84    Checks.Initialize;
  85
  86    --  Create package Standard
  87
  88    CStand.Create_Standard;
  89
  90    --  Read and process gnat.adc file if one is present
  91
  92    if Opt.Config_File then
  93
  94       --  We always analyze the gnat.adc file with style checks off,
  95       --  since we don't want a miscellaneous gnat.adc that is around
  96       --  to discombobulate intended -gnatg compilations.
  97
  98       Opt.Style_Check := False;
  99
 100       --  Capture current suppress options, which may get modified
 101
 102       Scope_Suppress := Opt.Suppress_Options;
 103
 104       Name_Buffer (1 .. 8) := "gnat.adc";
 105       Name_Len := 8;
 106       Source_gnat_adc := Load_Config_File (Name_Enter);
 107
 108       if Source_gnat_adc /= No_Source_File then
 109          Initialize_Scanner (No_Unit, Source_gnat_adc);
 110          Pragmas := Par (Configuration_Pragmas => True);
 111
 112          if Pragmas /= Error_List
 113            and then Operating_Mode /= Check_Syntax
 114          then
 115             Prag := First (Pragmas);
 116             while Present (Prag) loop
 117                Analyze_Pragma (Prag);
 118                Next (Prag);
 119             end loop;
 120          end if;
 121       end if;
 122
 123       --  Restore style check, but if gnat.adc turned on checks, leave on!
 124
 125       Opt.Style_Check := Save_Style_Check or Style_Check;
 126
 127       --  Capture any modifications to suppress options from config pragmas
 128
 129       Opt.Suppress_Options := Scope_Suppress;
 130    end if;
 131
 132    --  Read and process the configuration pragmas file if one is present
 133
 134    if Config_File_Name /= null then
 135
 136       declare
 137          New_Pragmas        : List_Id;
 138          Style_Check_Saved  : constant Boolean  := Opt.Style_Check;
 139          Source_Config_File : Source_File_Index := No_Source_File;
 140
 141       begin
 142          --  We always analyze the config pragmas file with style checks off,
 143          --  since we don't want it to discombobulate intended
 144          --  -gnatg compilations.
 145
 146          Opt.Style_Check := False;
 147
 148          --  Capture current suppress options, which may get modified
 149
 150          Scope_Suppress := Opt.Suppress_Options;
 151
 152          Name_Buffer (1 .. Config_File_Name'Length) := Config_File_Name.all;
 153          Name_Len := Config_File_Name'Length;
 154          Source_Config_File := Load_Config_File (Name_Enter);
 155
 156          if Source_Config_File = No_Source_File then
 157             Osint.Fail
 158               ("cannot find configuration pragmas file ",
 159                Config_File_Name.all);
 160          end if;
 161
 162          Initialize_Scanner (No_Unit, Source_Config_File);
 163          New_Pragmas := Par (Configuration_Pragmas => True);
 164
 165          if New_Pragmas /= Error_List
 166            and then Operating_Mode /= Check_Syntax
 167          then
 168             Prag := First (New_Pragmas);
 169             while Present (Prag) loop
 170                Analyze_Pragma (Prag);
 171                Next (Prag);
 172             end loop;
 173          end if;
 174
 175          --  Restore style check, but if the config pragmas file
 176          --  turned on checks, leave on!
 177
 178          Opt.Style_Check := Style_Check_Saved or Style_Check;
 179
 180          --  Capture any modifications to suppress options from config pragmas
 181
 182          Opt.Suppress_Options := Scope_Suppress;
 183       end;
 184
 185    end if;
 186
 187    --  If there was a -gnatem switch, initialize the mappings of unit names to
 188    --  file names and of file names to path names from the mapping file.
 189
 190    if Mapping_File_Name /= null then
 191       Fmap.Initialize (Mapping_File_Name.all);
 192    end if;
 193
 194    --  We have now processed the command line switches, and the gnat.adc
 195    --  file, so this is the point at which we want to capture the values
 196    --  of the configuration switches (see Opt for further details).
 197
 198    Opt.Register_Opt_Config_Switches;
 199
 200    --  Initialize the scanner. Note that we do this after the call to
 201    --  Create_Standard, which uses the scanner in its processing of
 202    --  floating-point bounds.
 203
 204    Initialize_Scanner (Main_Unit, Source_Index (Main_Unit));
 205
 206    --  Output header if in verbose mode or full list mode
 207
 208    if Verbose_Mode or Full_List then
 209       Write_Eol;
 210
 211       if Operating_Mode = Generate_Code then
 212          Write_Str ("Compiling: ");
 213       else
 214          Write_Str ("Checking: ");
 215       end if;
 216
 217       Write_Name (Full_File_Name (Current_Source_File));
 218
 219       if not Debug_Flag_7 then
 220          Write_Str (" (source file time stamp: ");
 221          Write_Time_Stamp (Current_Source_File);
 222          Write_Char (')');
 223       end if;
 224
 225       Write_Eol;
 226    end if;
 227
 228    --  Here we call the parser to parse the compilation unit (or units in
 229    --  the check syntax mode, but in that case we won't go on to the
 230    --  semantics in any case).
 231
 232    declare
 233       Discard : List_Id;
 234
 235    begin
 236       Discard := Par (Configuration_Pragmas => False);
 237    end;
 238
 239    --  The main unit is now loaded, and subunits of it can be loaded,
 240    --  without reporting spurious loading circularities.
 241
 242    Set_Loading (Main_Unit, False);
 243
 244    --  Now on to the semantics. We skip the semantics if we are in syntax
 245    --  only mode, or if we encountered a fatal error during the parsing.
 246
 247    if Operating_Mode /= Check_Syntax
 248      and then not Fatal_Error (Main_Unit)
 249    then
 250       --  Reset Operating_Mode to Check_Semantics for subunits. We cannot
 251       --  actually generate code for subunits, so we suppress expansion.
 252       --  This also corrects certain problems that occur if we try to
 253       --  incorporate subunits at a lower level.
 254
 255       if Operating_Mode = Generate_Code
 256          and then Nkind (Unit (Cunit (Main_Unit))) = N_Subunit
 257       then
 258          Operating_Mode := Check_Semantics;
 259       end if;
 260
 261       --  Analyze (and possibly expand) main unit
 262
 263       Scope_Suppress := Suppress_Options;
 264       Semantics (Cunit (Main_Unit));
 265
 266       --  Cleanup processing after completing main analysis
 267
 268       if Operating_Mode = Generate_Code
 269          or else (Operating_Mode = Check_Semantics
 270                    and then Tree_Output)
 271       then
 272          Instantiate_Bodies;
 273       end if;
 274
 275       if Operating_Mode = Generate_Code then
 276
 277          if Inline_Processing_Required then
 278             Analyze_Inlined_Bodies;
 279          end if;
 280
 281          --  Remove entities from program that do not have any
 282          --  execution time references.
 283
 284          if Debug_Flag_UU then
 285             Collect_Garbage_Entities;
 286          end if;
 287
 288          Check_Elab_Calls;
 289
 290          --  Build unit exception table. We leave this up to the end to
 291          --  make sure that all the necessary information is at hand.
 292
 293          Exp_Ch11.Generate_Unit_Exception_Table;
 294       end if;
 295
 296       --  List library units if requested
 297
 298       if List_Units then
 299          Lib.List;
 300       end if;
 301
 302       --  Output any messages for unreferenced entities
 303
 304       Output_Unreferenced_Messages;
 305       Sem_Warn.Check_Unused_Withs;
 306    end if;
 307
 308    --  Qualify all entity names in inner packages, package bodies, etc.,
 309    --  except when compiling for the JVM back end, which depends on
 310    --  having unqualified names in certain cases and handles the generation
 311    --  of qualified names when needed.
 312
 313    if not Java_VM then
 314       Exp_Dbug.Qualify_All_Entity_Names;
 315       Exp_Dbug.Generate_Auxiliary_Types;
 316    end if;
 317
 318    --  Dump the source now. Note that we do this as soon as the analysis
 319    --  of the tree is complete, because it is not just a dump in the case
 320    --  of -gnatD, where it rewrites all source locations in the tree.
 321
 322    Sprint.Source_Dump;
 323
 324    --  If a mapping file has been specified by a -gnatem switch,
 325    --  update it if there has been some sourcs that were not in the mappings.
 326
 327    if Mapping_File_Name /= null then
 328       Fmap.Update_Mapping_File (Mapping_File_Name.all);
 329    end if;
 330
 331 end Frontend;