Anyone interested in resurrecting an open source strict Ada 83 (mil-std 1815A) compiler?

General
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Some short news about the Ada 83 compiler. The TEXT_IO package has progressed and the private record type FILE_TYPE with a FILE_NAME_BUFFER is now used, a file can be created opened and deleted under Linux. I had to implement string slices because the FILE_TYPE has no discriminant, that means the file name must be kept in a larger fixed size string buffer with name length aside and the file name is a slice when used. I keep on to implement text file PUT, GET and other services.

The notion of type template or “patron de type” or “use info” is effectively very important in Ada, a variable has a data part and a “use info part”. This is implemented with two pointers, a pointer doublet. The use info part gives information on how to use the data part ; for example the 'FIRST and 'LAST for a string or a slice are in this “use info” with array component size.
This characteristic explains the Rational R1000 memory structure with its various stacks. It seems to me that the usual work stack can be used with less extremist policy than in the R1000 and can contain also use info and data blocks, with the conditions that their size is fixed and known at compile time. Blocks whose size is fixed but only known at runtime can be allocated in another stack with parallel frame context, and blocks whose size can vary, allocated in the heap.

Developping with fasm intermediate text is handy for debugging because everything is readable and can be edited to correct or try something. Inserting a breakpoint trap with a “db 0xCC” in the fasm text allows for gdb stop at will on x86. Debugging on gdb can be done with “lay asm”, “lay reg”, “run”, “x/” and so on.

63

Hello to all, one year later, some news of the TLALOC strict Ada 83 compiler all written in Ada 83 itself. It progresses, slowly, TEXT_IO can put/get enums, integers, floats. The fasmg macros stack machine can compute with floats. Some vicious stack bugs have been corrected. I am working on DIRECT_IO block version then full version able to compile some things as : package STRING_IO is new DIRECT_IO( STRING ). Two repositories are available and roughly in lock step, the historical one on Framagit, a second one for safety on Github : GitHub - ViMoBr/Ada83_TLALOC · GitHub . If someone is interested and needs information on how to use or develop this experimental and relatively complicated (but very interesting) system. An example of what it currently compiles and executes :

with TEXT_IO;
use  TEXT_IO;
procedure ENUM_TEST
is

  type COULEUR	is ( BLEU, BLANC, ROUGE );
  type JOUR	is ( LUNDI, MARDI, MERCREDI, JEUDI, VENDREDI, SAMEDI, DIMANCHE );

  package IO_COULEUR	is new ENUMERATION_IO( COULEUR );
  package IO_JOUR		is new ENUMERATION_IO( JOUR );
  package IO_MODE		is new ENUMERATION_IO( FILE_MODE );

  C	: COULEUR;
  J	: JOUR;

  G	: FILE_TYPE;

begin

  -- === 1. PUT basique ===
  PUT_LINE( "=== 1. PUT basique ===" );
  IO_COULEUR.PUT( BLEU );	NEW_LINE;
  IO_COULEUR.PUT( BLANC );	NEW_LINE;
  IO_COULEUR.PUT( ROUGE );	NEW_LINE;

  -- === 2. PUT avec WIDTH ===
  PUT_LINE( "=== 2. PUT avec WIDTH ===" );
  PUT( "[" );  IO_COULEUR.PUT( BLEU, WIDTH => 10 );   PUT_LINE( "]" );
  PUT( "[" );  IO_COULEUR.PUT( ROUGE, WIDTH => 10 );  PUT_LINE( "]" );

  -- === 3. PUT LOWER_CASE ===
  PUT_LINE( "=== 3. PUT LOWER_CASE ===" );
  IO_COULEUR.PUT( BLEU,  SET => LOWER_CASE );	NEW_LINE;
  IO_COULEUR.PUT( BLANC, SET => LOWER_CASE );	NEW_LINE;
  IO_COULEUR.PUT( ROUGE, SET => LOWER_CASE );	NEW_LINE;

  -- === 4. PUT via variable ===
  PUT_LINE( "=== 4. PUT via variable ===" );
  C := BLANC;  IO_COULEUR.PUT( C );  NEW_LINE;
  C := ROUGE;  IO_COULEUR.PUT( C );  NEW_LINE;

  -- === 5. PUT sans FILE ===
  PUT_LINE( "=== 5. PUT sans FILE ===" );
  IO_COULEUR.PUT( BLEU );  NEW_LINE;

  -- === 6. Type JOUR ===
  PUT_LINE( "=== 6. Type JOUR ===" );
  IO_JOUR.PUT( LUNDI );     NEW_LINE;
  IO_JOUR.PUT( MERCREDI );  NEW_LINE;
  IO_JOUR.PUT( DIMANCHE );  NEW_LINE;

  -- === 7. JOUR WIDTH+LOWER_CASE ===
  PUT_LINE( "=== 7. JOUR WIDTH+LOWER_CASE ===" );
  PUT( "[" );
  IO_JOUR.PUT( SAMEDI, WIDTH => 12, SET => LOWER_CASE );
  PUT_LINE( "]" );

  -- === 8. FILE_MODE ===
  PUT_LINE( "=== 8. FILE_MODE ===" );
  IO_MODE.PUT( IN_FILE );   NEW_LINE;
  IO_MODE.PUT( OUT_FILE );  NEW_LINE;

  -- === 9. Boucle couleurs ===
  PUT_LINE( "=== 9. Boucle couleurs ===" );
  for  I in COULEUR'FIRST .. COULEUR'LAST  loop
    IO_COULEUR.PUT( I );  PUT( " " );
  end loop;
  NEW_LINE;

  -- === 10. Boucle jours ===
  PUT_LINE( "=== 10. Boucle jours ===" );
  for  I in JOUR'FIRST .. JOUR'LAST  loop
    IO_JOUR.PUT( I, WIDTH => 10 );
  end loop;
  NEW_LINE;

  -- === 11. GET fichier ===
  PUT_LINE( "=== 11. GET fichier ===" );
  CREATE( G, OUT_FILE, "enum_data.dat" );
  PUT_LINE( G, "ROUGE" );
  PUT_LINE( G, "BLANC" );
  PUT_LINE( G, "BLEU" );
  CLOSE( G );

  OPEN( G, IN_FILE, "enum_data.dat" );
  PUT( "lecture 1..." ); IO_COULEUR.GET( G, C );
  PUT( "Lu 1 : " );  IO_COULEUR.PUT( C );  NEW_LINE;
  PUT( "lecture 2..." ); IO_COULEUR.GET( G, C );
  PUT( "Lu 2 : " );  IO_COULEUR.PUT( C );  NEW_LINE;
  PUT( "lecture 3..." ); IO_COULEUR.GET( G, C );
  PUT( "Lu 3 : " );  IO_COULEUR.PUT( C );  NEW_LINE;
  CLOSE( G );


  -- === 12. GET casse mixte ===
  PUT_LINE( "=== 12. GET casse mixte ===" );
  CREATE( G, OUT_FILE, "enum_data2.dat" );
  PUT_LINE( G, "Rouge" );
  PUT_LINE( G, "blanc" );
  PUT_LINE( G, "BLEU" );
  CLOSE( G );

  OPEN( G, IN_FILE, "enum_data2.dat" );
  PUT( "lecture 1..." ); IO_COULEUR.GET( G, C );
  PUT( "Lu 1 : " );  IO_COULEUR.PUT( C );  NEW_LINE;
  PUT( "lecture 2..." ); IO_COULEUR.GET( G, C );
  PUT( "Lu 2 : " );  IO_COULEUR.PUT( C );  NEW_LINE;
  PUT( "lecture 3..." ); IO_COULEUR.GET( G, C );
  PUT( "Lu 3 : " );  IO_COULEUR.PUT( C );  NEW_LINE;
  CLOSE( G );

  -- === 13. GET JOUR ===
  PUT_LINE( "=== 13. GET JOUR ===" );
  CREATE( G, OUT_FILE, "jour_data.dat" );
  PUT_LINE( G, "LUNDI" );
  PUT_LINE( G, "vendredi" );
  PUT_LINE( G, "Dimanche" );
  CLOSE( G );

  OPEN( G, IN_FILE, "jour_data.dat" );
  IO_JOUR.GET( G, J );
  PUT( "Lu 1 : " );  IO_JOUR.PUT( J );  NEW_LINE;
  IO_JOUR.GET( G, J );
  PUT( "Lu 2 : " );  IO_JOUR.PUT( J );  NEW_LINE;
  IO_JOUR.GET( G, J );
  PUT( "Lu 3 : " );  IO_JOUR.PUT( J );  NEW_LINE;
  CLOSE( G );

  -- === 14. Roundtrip PUT-GET ===
  PUT_LINE( "=== 14. Roundtrip ===" );
  CREATE( G, OUT_FILE, "roundtrip.dat" );
  for  I in COULEUR'FIRST .. COULEUR'LAST  loop
    IO_COULEUR.PUT( G, I );
    NEW_LINE( G );
  end loop;
  CLOSE( G );

  OPEN( G, IN_FILE, "roundtrip.dat" );
  for  I in COULEUR'FIRST .. COULEUR'LAST  loop
    IO_COULEUR.GET( G, C );
    IO_COULEUR.PUT( C );  PUT( " " );
  end loop;
  NEW_LINE;
  CLOSE( G );

  -- === 15. Roundtrip JOUR ===
  PUT_LINE( "=== 15. Roundtrip JOUR ===" );
  CREATE( G, OUT_FILE, "jour_rt.dat" );
  for  I in JOUR'FIRST .. JOUR'LAST  loop
    IO_JOUR.PUT( G, I );
    NEW_LINE( G );
  end loop;
  CLOSE( G );

  OPEN( G, IN_FILE, "jour_rt.dat" );
  for  I in JOUR'FIRST .. JOUR'LAST  loop
    IO_JOUR.GET( G, J );
    IO_JOUR.PUT( J );  PUT( " " );
  end loop;
  NEW_LINE;
  CLOSE( G );

  -- === 16. Boucle couleurs avec GET ===
  PUT_LINE( "=== 16. Boucle GET couleurs ===" );
  CREATE( G, OUT_FILE, "enum_data.dat" );
  IO_COULEUR.PUT( G, ROUGE );  NEW_LINE( G );
  IO_COULEUR.PUT( G, BLEU );   NEW_LINE( G );
  IO_COULEUR.PUT( G, BLANC );  NEW_LINE( G );
  CLOSE( G );

  OPEN( G, IN_FILE, "enum_data.dat" );
  for  I in 1 .. 3  loop
    IO_COULEUR.GET( G, C );
    IO_COULEUR.PUT( C );  PUT( " " );
  end loop;
  NEW_LINE;
  CLOSE( G );

  -- === 17. GET sans FILE (console) - commente pour automatiser ===
   PUT_LINE( "=== 17. GET console ===" );
   PUT( "Entrez une couleur : " );
   IO_COULEUR.GET( C );
   PUT( "Lu : " ); IO_COULEUR.PUT( C ); NEW_LINE;

  PUT_LINE( "=== FIN ===" );

end	ENUM_TEST;

I precise that TLALOC compiles its own source code entirely in DIANA and some modules are effectively compiled to fasmg macros. Once support packages work satisfactorily, the aim is to progressively compile the compiler to fasmg piece after piece (beginning with page-manager and so on).