Videos matching: ADA

This is really an annoying problem. I have a record type that wraps various base types and now I need it to be able to store a vector (from Ada.Cont...More

This is really an annoying problem. I have a record type that wraps various base types and now I need it to be able to store a vector (from Ada.Containers.Vectors) in itself! I guess that's not possible but can anyone give me advice on how to solve this problem in another way perhaps? To give you a better idea of what I'm up to, here is what does not work:

with Base_Types; use Base_Types;
with Ada.Strings.Wide_Unbounded; use Ada.Strings.Wide_Unbounded;
with Ada.Containers.Vectors;
with Green_Tasks; use Green_Tasks;
with Ada.Unchecked_Deallocation;

package Boxed_Types is

   type String_Ptr is access Unbounded_Wide_String;
   procedure Free_Unbounded_Wide_String is new Ada.Unchecked_Deallocation
     (Object => Unbounded_Wide_String, Name => String_Ptr);
   type Vector_Ptr; -- this won't work

   type Type_T is (T_Null, T_UInt64, T_Text, T_Bool, T_GTask, T_Vector);
   type Item (IType : Type_T := T_Null) is record
      case IType is
         when T_Null   => null;
         when T_UInt64 => UInt64      : UInteger_64;
         when T_Text   => String      : String_Ptr;
         when T_Bool   => Bool        : Boolean;
         when T_GTask  => Green_Task  : Green_Task_Ptr;
         when T_Vector => Item_Vector : Vector_Ptr;     -- error here 
      end case;
   end record;

   package Item_Vectors is new Ada.Containers.Vectors
     (Index_Type   => Natural,
      Element_Type => Item);
   use Item_Vectors;
   type Vector_Ptr is access Vector;
end Boxed_Types;

This gives me the not so unexpected error "invalid use of type before it's full declaration" for Vector_Ptr. However, I cannot instantiate the vector package before I have declared Item either, and I really need the vector and the base types wrapped into one record type. (It's for Interpreter I'm writing in my spare time; the VM must store various different types on the stack, in heterogenous arrays, manipulate them, etc..)

Will I have to break type safety entirely and mess around with address to access conversions or is there a cleaner solution?

So here is a piece of my body file. I am getting the error "words.adb:75:42: actual for "S" must be a variable".

procedure Remove_Ch...More

I am using Ada for the first time and have a txt file with the following written on it

      23.000000#:599.659058,-67.651642
More

How can I load two packages with the same name but located in seperate folders?

Example:

/src/alpha/foopackage.ads
/src/be...More

I have an enumerated type that needs to be 4 bits but when I declare a variable of that type the compiler assigns that variable 8 bits.

Bel...More

I have an enumerated type that needs to be 4 bits but when I declare a variable of that type the compiler assigns that variable 8 bits.

Below is a simplified version of the code.

subtype ab_range_index is word range 0..3;
type ab_buffer_type is array(ab_range_index) of bit;

type Buffer is record
   ...
   var1        : some_buffer_type;
   Orig_AB_var : ab_buffer_type; 
   ...
end record;
for Buffer use record
  ...
  var1         at 16 range 0..5;
  Orig_AB_var  at 16 range 6..9;
  ...
end record;
...
type AB_type is (A,B);
for AB_type use (A => 0, B => 5);
for AB_type'Size use 4;
...
procedure Proc(AB_buff : ab_buffer_type) is 
AB_var : AB_type;                      -- AB_var'Size returns 8 in debugger.
for AB_var use at AB_buff'Address;
begin
   data_valid = AB_var'valid;          -- returns false since the variable 
                                       -- contains extra bits
   ...     

This all worked under previous gnat versions but not under gnat 4.4.6. I understand that gnat is in compliance with the Ada spec.

Is there a way to force the compiler to make the AB_var in the above example to be 4 bits? I've tried 'Object_Size but it needs to be a multiple of 8 bits.

I'm coming from C/C++ on embedded systems and all the time inside a function we use a static variable so that the value is retained throughout calls...More

I'm coming from C/C++ on embedded systems and all the time inside a function we use a static variable so that the value is retained throughout calls.

In Ada, it seems like this is only done with the equivalent of file-level static variables. Is there an Ada equivalent.

C++:

function Get_HW_Counter() {
   static int count = 0;
   return ++count;
}

Ada:??

Dont know what this oop pattern is called but how can I do the same pattern in Ada? For example this code:

interface Vehicle{
    st...More

I have a main package with a normal spec and body file. I am trying to create child packages of the parent, but want them in a separate compilation ...More

I have a main package with a normal spec and body file. I am trying to create child packages of the parent, but want them in a separate compilation file(s). I can easily get it done if it is just a package body, or if it is a subprogram/proc/func. However, I can't get it to let me make a child spec file.

The reason I am doing this is because I want to have information in a child that is available to other children of the same parent. I know I can do this by just including the spec portion in the parent, but that is making my parent file pretty big.

Is this even possible, or do I have no choice but to make another root unit? Or just leave everything spec wise in the parent?

I tried:

in parent: package Child1 is separate; (also tried Parent.Child1 but that gave compiles errors

in child:

separate(Parent)

package Parent.Child1 is
....
end Parent.Child1;

Ideas? Just not possible?

Update: I am compiling with Green Hills Multi Compiler. Ada95 language version, non-OO project.

I have a question regarding the "select then abort" language construct in Ada. The task I'm using looks something like:

select
  del...More

Lets say I have

    function x return boolean is 
          type range0 is range 1..1; 
        begin 
         canse x is 
       ...More

Basically, I have 2 files ( .adb and .ads). I am totally new to Ada and also how to compile 2 files. The program is of a basic stack implementation....More

Basically, I have 2 files ( .adb and .ads). I am totally new to Ada and also how to compile 2 files. The program is of a basic stack implementation. I got this compile error when I compiled the .adb file.

$ gcc -c test_adt_stack.adb
abstract_char_stack.ads:22:01: end of file expected, file can have only one compilation unit

The 2 files I have are: abstract_char_stack.ads

-----------------------------------------------------------
package Abstract_Char_Stack is
  type Stack_Type is private;
  procedure Push(Stack : in out Stack_Type;
                 Item  : in Character);
  procedure Pop (Stack : in out Stack_Type;
                 Char  : out Character);
private
  type Space_Type is array(1..8) of Character;
  type Stack_Type is record
    Space : Space_Type;
    Index : Natural := 0;
  end record;
end Abstract_Char_Stack;
-----------------------------------------------------------
package body Abstract_Char_Stack is
----------------------------------------------
  procedure Push(Stack : in out Stack_Type;
                  Item : in Character) is
  begin
    Stack.Index := Stack.Index + 1;
    Stack.Space(Stack.Index) := Item;
  end Push;
--------------------------------------------
  procedure Pop (Stack : in out Stack_Type;
                 Char  : out Character) is
  begin
    Char := Stack.Space(Stack.Index);
    Stack.Index := Stack.Index - 1;
  end Pop;
--------------------------------------------
end Abstract_Char_Stack;

and the other one is test_adt_stack.adb

-----------------------------------------------------------
with Ada.Text_IO; use Ada.Text_IO;
with Abstract_Char_Stack; use Abstract_Char_Stack;
procedure Test_ADT_Stack is
  S1 : Stack_Type;
  S2 : Stack_Type;
  Ch : Character;
begin
  Push(S1,'H'); Push(S1,'E');  
  Push(S1,'L'); Push(S1,'L');
  Push(S1,'O');                          -- S1 holds O,L,L,E,H

  for I in 1..5 loop
    Pop(S1, Ch);  
    Put(Ch);                             -- displays OLLEH
    Push(S2,Ch); 
  end loop;                              -- S2 holds H,E,L,L,O

  New_Line;
  Put_Line("Order is reversed");

  for I in 1..5 loop
    Pop(S2, Ch);
    Put(Ch);                             -- displays HELLO
  end loop;

end Test_ADT_Stack;
-----------------------------------------------------------

What am I doing wrong? I just want to have it compile and display what it's supposed to do. This was a study the program kind of assignment. But I can't make it compile or don't know if I am doing it right.

In Ada you can define so called 'mod' and 'More

In Ada you can define so called 'mod' and 'range' types:

type Unsigned_n is mod 2**n;
type Range_Type is range -5 .. 10;

How are these implemented at the language machine level? What kind of performance penalty do you experience when performing operations on these types?

I've had some difficulty trying to obtain a working Ada compiler.

I had been attempting to install avr-ada on a Windows system. I've asked q...More

I've had some difficulty trying to obtain a working Ada compiler.

I had been attempting to install avr-ada on a Windows system. I've asked questions and been provided some good suggestions, but not quite there yet.

I've since tried to install and use GNAT on a Mint Linux system, but I keep getting stuck. I've downloaded and installed gcc-4.8.0.

Installed ok.

I then want to build the GNAT Ada compiler, but the manual is not exactly useful.

Every time I try to find installation instruction for GNAT, I find nothing of immediate use.

For example the details I have found state:

"Building the Ada compiler has special requirements, see below" But do not appear to have any content for how do build the Ada compiler anywhere.

Any ideas?

I am attempting to build an Expression tree from fully parenthesized infix notation in Ada. I am building the tree recursively. Each node has a da...More

I am attempting to build an Expression tree from fully parenthesized infix notation in Ada. I am building the tree recursively. Each node has a data field, and a pointer to left and right children. The following is what I have put together for implementation.

WITH Ada.Integer_Text_IO, Ada.Text_IO;
USE Ada.Text_IO;

PACKAGE BODY Tree_Expression IS
   FUNCTION To_String (
         Input : Tree_String)
     RETURN String IS
      Last : Natural := 0;
   BEGIN
      FOR I IN Input'RANGE LOOP
         IF Input(I) /= ' ' THEN
            Last := Last + 1;
         END IF;
      END LOOP;
      RETURN Input(Input'First .. Last);
   END To_String;

   FUNCTION To_Number (
         Input : String)
     RETURN Float IS
      Output : Integer;
      First  : Integer  := - 1;
      Last   : Positive;
   BEGIN
      FOR I IN Input'RANGE LOOP
         IF Input(I) IN '0'..'9' THEN
            First := I;
            EXIT;
         END IF;
      END LOOP;
      IF First = -1 THEN
         RAISE Number_Error;
      END IF;
      IF First = Input'First THEN
         Ada.Integer_Text_IO.Get(
            From => Input,
            Item => Output,
            Last => Last);
         RETURN Float(Output);
      ELSE
         Ada.Integer_Text_IO.Get(Input(First .. Input'Last), Output, Last);
         RETURN Float(Output);
      END IF;
   END To_Number;

   FUNCTION To_Char (
         Input : String)
     RETURN Character IS
   BEGIN
      FOR I IN Input'RANGE LOOP
         IF Input(I) = '*' OR Input(I) = '/' OR Input(I) = '+' OR Input(I) = '-' OR Input(I) = '^' THEN
            RETURN Input(I);
         END IF;
      END LOOP;
      RAISE Operator_Error;
   END To_Char;

   FUNCTION Construct_ExpressionTree (
         Expression_String : String;
         First,
         Last              : Natural)
     RETURN Expression_Node_Ptr IS
      Depth           : Natural     := 0;
      Pos             : Natural     := 0;
      Operator        : Character   := ' ';
      Number_String   : Tree_String;
      Operator_String : Tree_String;
      Build_Num_Str   : Natural     := Number_String'First;
   BEGIN
      FOR I IN First..Last LOOP
         CASE(Expression_String(I)) IS
            WHEN '(' =>
               Depth := Depth + 1;
            WHEN ')' =>
               Depth := Depth - 1;
            WHEN '+'|'-'|'*'|'/'|'^' =>
               IF Depth = 1 THEN
                  Pos := I;
                  Operator := Expression_String(I);
                  EXIT;
               END IF;
            WHEN OTHERS =>
               NULL;
         END CASE;
      END LOOP;
      IF Operator = '+' OR Operator = '-' OR Operator = '*' OR Operator = '/' OR Operator = '^' THEN
         Operator_String(Operator_String'First) := Operator;
         FOR I IN Operator_String'RANGE LOOP
            IF I > Operator_String'First THEN
               Operator_String(I) := ' ';
            END IF;
         END LOOP;
         RETURN Binary_Expression_Tree.Create_Node(Operator_String, Construct_ExpressionTree(Expression_String, 
            Expression_String'First+1, Pos-1), Construct_ExpressionTree(Expression_String, Pos+1, Expression_String'Last-1));
      ELSE
         FOR I IN First..Last LOOP
            IF Expression_String(I) IN '0'..'9' THEN
               Number_String(Build_Num_Str) := Expression_String(I);
               Build_Num_Str := Build_Num_Str +1;
            ELSIF Expression_String(I) = ')' THEN
               EXIT;
            ELSE
               NULL;
            END IF;
         END LOOP;
         IF Build_Num_Str = Number_String'First THEN
            RAISE Number_Error;
         END IF;
         FOR I IN Build_Num_Str..Number_String'Last LOOP
            Number_String(I) := ' ';
         END LOOP;
         RETURN Binary_Expression_Tree.Create_Node(Number_String, NULL, NULL);
      END IF;

   END Construct_ExpressionTree;

   FUNCTION Evaluate_Expression (
         Node : Expression_Node_Ptr)
     RETURN Float IS
      FUNCTION Eval (
            Node : Expression_Node_Ptr)
        RETURN Float IS
         Data     : Tree_String := Binary_Expression_Tree.Get_Data (Node);
         Operator : Character;
      BEGIN
         Operator := To_Char(Data);
         CASE Operator IS
            WHEN '+' =>
               RETURN Eval(Binary_Expression_Tree.Get_Left_Child(Node)) + Eval(Binary_Expression_Tree.Get_Right_Child(Node));
            WHEN '-' =>
               RETURN Eval(Binary_Expression_Tree.Get_Left_Child(Node)) - Eval(Binary_Expression_Tree.Get_Right_Child(Node));
            WHEN '*' =>
               RETURN Eval(Binary_Expression_Tree.Get_Left_Child(Node)) * Eval(Binary_Expression_Tree.Get_Right_Child(Node));
            WHEN '/' =>
               RETURN Eval(Binary_Expression_Tree.Get_Left_Child(Node)) / Eval(Binary_Expression_Tree.Get_Right_Child(Node));
            WHEN '^' =>
               RETURN Eval(Binary_Expression_Tree.Get_Left_Child(Node)) ** Natural(Eval(Binary_Expression_Tree.Get_Right_Child(Node)));
            WHEN OTHERS =>
               RAISE Expression_Error;
         END CASE;
      EXCEPTION
         WHEN Operator_Error =>
            RETURN To_Number(Data);
      END Eval;
   BEGIN
      RETURN Eval (Node);
   END Evaluate_Expression;

   FUNCTION Infix_Notation (
         Node : Expression_Node_Ptr)
     RETURN String IS
   BEGIN
      RETURN Binary_Expression_Tree.Inorder_Traversal(Node);

   END Infix_Notation;

   FUNCTION Prefix_Notation (
         Node : Expression_Node_Ptr)
     RETURN String IS
   BEGIN
      RETURN Binary_Expression_Tree.Preorder_Traversal(Node);
   END Prefix_Notation;

   FUNCTION Postfix_Notation (
         Node : Expression_Node_Ptr)
     RETURN String IS
   BEGIN
      RETURN Binary_Expression_Tree.Postorder_Traversal(Node);
   END Postfix_Notation;

END Tree_Expression;

My issue is that when I enter an expression, for example, ((5+6)*(1-3)), the tree is being built incorrectly. My output from an in order traversal of the tree built from that expression is 5+6*5+6-3 instead of 5+6*1-3. Basically, the left child of the root's right child (1) is not being added to the tree, and (5+6) is being added again in its place.

Create_Node, which is a function called in the construction function, looks like:

FUNCTION Create_Node (
         Data        : Item_Type;
         Left_Child,
         Right_Child : Node_Ptr)
     RETURN Node_Ptr IS
   BEGIN
      RETURN NEW Node_Type'(Data, Left_Child, Right_Child);
   END Create_Node;

This is for homework - I'm just looking for pointers as to what is going wrong in general, and sections of my code that it would make sense to look at. Thanks in advance.

Edited after feedback: Here's my thought process, hopefully it tracks:
- Start by finding the operator at depth = 1, which will be the root node for the tree.
- Once I have that, I create a node, with everything to the left being sent back into the construct function as the left child, and everything to the right being sent back in as the right child. As I understand it, this is the recursive method to building the tree.
- Every time the function is called, it should find the operator at depth 1, which will be the next node down. If no operators are found, it should make leaf nodes with numbers. There's a loop there that parses input and builds a number string to store in the node, so multiple digits should work. I've been thinking about it, and I'm thinking something may be fishy with the First and Last being sent back into Construct_ExpressionTree.

And I was just playing with it and got a test case to work. I was sending the wrong info back into the function.

Im trying to use the System.Adress_image to list all the adress of the allocated objects in the program.

However I can only print the adres...More

Im trying to use the System.Adress_image to list all the adress of the allocated objects in the program.

However I can only print the adress for variables that I have. For example I have a stack and I can print all the stack elements adress. Then I remove the pointer to one of the stacks node so that object is not in the stack anymore.

The removed node is not automatically garbage collected(Ada 2005) so I would like to know the adress of that node. and why not the adress of all the allocated objects in the program?

How may I accomplish this task?

system package: http://www.adaic.org/resources/add_content/standards/05aarm/html/AA-13-7.html

Zombies is referred to "dead objects but still alive".

I have a folder with files containing some text. I am trying to go through all the files one after the other, and count how many times we see every...More

I have a folder with files containing some text. I am trying to go through all the files one after the other, and count how many times we see every word in the text files. I know how to open the file, but once I'm in the file I don't know how to read each word one after the other, and go to the next word.

If anyone has some ideas to guide me it'd be great.

Hello Im new to ada and I am trying to create some kind of unconstrained array and I can't figure out how to do it in ada.

package d...More

Please have a look at the following code

Formula.ads

package Formula is
   procedure CalculateFormula;
end ...More

Can anyone explain me the difference between the Ada "procedure" and "function"?

Please help.

Please have a look at the following code

Formula.ads

package Formula is
   procedure CalculateFormula;
end Formula;

Formula.adb

with Ada.Text_IO; use Ada.Text_IO;
with Formula; use Formula;

package body Formula is
   procedure CalculateFormula is

      package fom_io is new Ada.Float_Text_IO(Float);
      use fom_io;

      u : Float;
      t : Float;
      a : Float;
      answer : Float;

   begin
      put_line("Enter 'U'");
      get(u);

      put_line("Enter 'T'");
      get(t);

      put_line("Enter 'A'");
      get(a);

      answer = (u*t)+ 0.5(a(t*t));

      put("Answer is: ");
      put(answer,Fore => 1,Aft => 1,Exp => 1);
   end CalclualeFormula;
end Formula;

When I run this code, I get the following error

gnatmake -d -PC:\Users\yohan\Documents\Ada\Formula\formula.gpr
gcc -c -I- -gnatA C:\Users\yohan\Documents\Ada\Formula\formula.ads
cannot generate code for file formula.ads (package spec)
gnatmake: "C:\Users\yohan\Documents\Ada\Formula\formula.ads" compilation error

[2013-04-06 03:18:22] process exited with status 4 (elapsed time: 00.22s)

I am very new to Ada. Started coding few hours back. Please help me to get rid of the above issue. Thank you.

EDIT

formula.gpr

project Formula is

   for Main use ("formula.ads");

end Formula;

I need to create an hash function in Ada that takes a string and returns an integer. what I did so far is :

function hash(Word: un...More

In my VB6 application I make several calls to a COM server my team created from a Ada project (using GNATCOM). There are basically 2 methods availab...More

In my VB6 application I make several calls to a COM server my team created from a Ada project (using GNATCOM). There are basically 2 methods available on the COM server. Their prototypes in VB are:

Sub PutParam(Param As Parameter_Type, Value)
Function GetParam(Param As Parameter_Type)

where Parameter_Type is an enumerated type which distinguishes the many parameters I can put to/get from the COM server and 'Value' is a Variant type variable. PutParam() receives a variant and GetParam() returns a variant. (I don't really know why in the VB6 Object Browser there's no reference to the Variant type on the COM server interface...).

The product of this project has been used continuously this way for years without any problems in this interface on computers with Windows XP with SP2. On computers with WinXP SP3 we get the error 0x800706F7 "The stub received bad data" when trying to put parameters with the 'Long' type.

Does anybody have any clue on what could be causing this? The COM server is still being built in a system with SP2. Should make any difference building it on a system with SP3? (like when we build for X64 in X64 systems).

One of the calls that are causing the problem is the following (changed some var names):

Dim StructData As StructData_Type

StructData.FirstLong = 1234567
StructData.SecondLong = 8901234
StructData.Status = True

ComServer.PutParam(StructDataParamType, StructData)

Where the definition of StructData_Type is:

Type StructData_Type
    FirstLong As Long
    SecondLong As Long
    Status As Boolean
End Type

(the following has been added after the question was first posted)

The definition of the primitive calls on the interface of the COM server in IDL are presented below:

// Service to receive data
HRESULT PutParam([in] Parameter_Type Param, [in] VARIANT *Value);

//Service to send requested data
HRESULT GetParam([in] Parameter_Type Param, [out, retval] VARIANT *Value);

The definition of the structure I'm trying to pass is:

struct StructData_Type
{
   int FirstLong;
   int SecondLong;
   VARIANT_BOOL Status;
} StructData_Type;

I found it strange that this definition here is using 'int' as the type of FirstLong and SeconLong and when I check the VB6 object explorer they are typed 'Long'. Btw, when I do extract the IDL from the COM server (using a specific utility) those parameters are defined as Long.

Update:

I have tested the same code with a version of my COM server compiled for Windows 7 (different version of GNAT, same GNATCOM version) and it works! I don't really know what happened here. I'll keep trying to identify the problem on WinXP SP3 but It is good to know that it works on Win7. If you have a similar problem it may be good to try to migrate to Win7.

Please have a look at the following code

with text_io;
use text_io;

procedure hello is

begin
put_line("hello");
new_line(3);
end h...More

hi i need help with this simple iteration problem am trying to divide

number:Float:=55.0;
Loop 
number:=number/3.0;
put(number);
ex...More

I am am unable to get avr-elf-windows and WinAVR to work. I have managed to build the example supplied with avr-elf-windows (More

I am am unable to get avr-elf-windows and WinAVR to work. I have managed to build the example supplied with avr-elf-windows (ATmega2560). But if I try and expand to use another chip or start using the WinAVR supplied packages and projects I keep getting errors I cannot work out.

Method 1:

Modify the ATmega2560 example to use the WinAVR packages.

Changed:

with Atmega2560; use Atmega2560;

to:

with AVR; use AVR;
with AVR.Atmega328p; use AVR.atmega328p;

Create a project file to include:

with "C:\WinAVR-20100110\lib\gnat\avr.gpr";
with "C:\WinAVR-20100110\lib\gnat\avr_app.gpr";

Running make I get the following error:

avr-gnatmake: "C:\WinAVR-20100110\lib\gnat\avr_lib\avr-int_img.adb" compilation error

Great, I have a compilation issue, but I cannot see the error.

Method 2:

Open the above project file in GPS. Change the build setting to be gnatmake. GPS now starts reporting errors and warnings:

Project warning: object directory "avr_lib/avr5/obj" not found Project library directory "C:\WinAVR-20100110\lib\gnat\avr_lib\avr5\lib\" does not exist

The latter issue is very clearly the fact that I have not set up GPS correctly to tell it the values of microcontroller and architecture, but I cannot seem to find anything to resolve this.

Method 3:

To use the WinAVR set up directly using makefiles which then gives me the error:

avr-gnatmake: RTS path not valid: missing adainclude and adalib directories

If I follow the instructions I can find by searching the web I can only find details for building the required libraries under Linux.

Platform: Windows 7.

With the combination of the two answers above I have now managed to link my sample code. As to wether it will work on the Arduino, that is a different issue.

Many thanks for the help.

I have found it a bit frustrating to get this far, and I wonder if there are others out there who may just give up on Ada on the Arduino and go back to the Arduino IDE and therefore missing out on the opportunity to learn a language with more structure. There are many misleading pages out there that also do not help.

I've been reading a little bit about tasks in ada at http://en.wikiboo...More

I've been reading a little bit about tasks in ada at http://en.wikibooks.org/wiki/Ada_Programming/Tasking and thought that i'll write a little thing with tasks myself. Since i've read a small course on Pintos recently i thought i'd implement a little readers-writers algorithm. This is my attempt at it:

procedure Test_Queue is

   type Int_Array is array(1..10) of Integer;

   task type Queue is
      entry Quit;
      entry Pop(Elem : out Integer);
      entry Push(Elem : in Integer);
   end Queue;

   task body Queue is
      Elems_In_Queue : Integer := 0;
      Q : Int_Array;
   begin
      loop
         select
            accept Push(Elem : in Integer) do
               Put_Line("Push");
               Elems_In_Queue := Elems_In_Queue + 1;
               Q(Elems_In_Queue) := Elem;
            end Push;
         or
            when Elems_In_Queue > 0 =>
               accept Pop(Elem : out Integer) do
                    Put_Line("Pop");
                Elem := Q(Elems_In_Queue);
                Elems_In_Queue := Elems_In_Queue - 1;
               end Pop;
         else
            delay 1.0;
            Put_Line("Waited");
            accept Quit;
            exit;
         end select;
      end loop;
      Put_Line("Got out of the loop");
   end Queue;

   Q : Queue;
   X : Integer;

begin
   Put_Line("Started");
   Q.Push(10);
   Put_Line("Pushed");
   Q.Push(11);
   Put_Line("Pushed");
   Q.Pop(X);
   Put_Line("Integer:" & Integer'Image(X));
   Q.Quit;
   Put_Line("Done");
end Test_Queue;

Might be worth mentioning that the behaviour i would like to see is that when no operations (push/pop) have been made to the queue/stack for 1 second i would like the task to terminate/exit the infinite loop.

But this just outputs "Started" and then goes to my delay 1.0 and outputs "Wait". This is not exactly what I expected since i have accept for at least push and that is the first thing i call. Where have i been thinking wrong and why doesn't this work? Also, are there any more sources with some examples as for how to do tasking in Ada? I managed to implement this by creating a Semaphore and Lock in 2 different tasks but that seemed to be a bad solution and not very adaesque.

I have a set of single threaded C++ mains that have a bulk of their code developed in Ada. This is being built in Atego (Rational) Apex Duo, and ta...More

I have a set of single threaded C++ mains that have a bulk of their code developed in Ada. This is being built in Atego (Rational) Apex Duo, and targets 32 bit RHEL 6.3 Linux. The exec is a Class system I developed that includes sockets, a state machine, and a timer class that is the heart of the exec. The class system is used to build and execute 14 separate execs on 6 different systems that communicate via sockets. They all use the same Class system and configure themselves at startup based on an INI file.

The execs frame either at 50 or 60 Hz using the linux system clock via gettimeofday

struct timeval {
    time_t      tv_sec;     /* seconds */
    suseconds_t tv_usec;    /* microseconds */
};

and a simple non-busywait algorithm to produce the desired scheduler.

The problem I am facing at the moment is that these execs fail (seemingly) randomly. The failure appears to be that they simply stop framing. I have encapsulated all of the runtime C++ procedures in "try{} catch(...){}" and nothing is caught. Likewise, the Ada routines are protected with Exception Handlers that do not get hit.

The exec will often run happily for 30 minutes to over an hour before failure. No indication of memory creep is evident (using System Monitor). I have attached the Atego Rational Graphical Debugger to the already running execs, to no avail. When one finally fails, there is nothing in the call stack and the only indication in the debugger log is that the application has "Exited with status 255".

I am afraid that a (Linux) system routine or driver somewhere in the system is calling Exit. It seems apparent that SOMETHING is calling exit!

Anyone have any idea how I can further dubug this problem?

Why does Ada compiler let range violations pass? It does give warning, but why does it let it pass if it is an error in any case? Is there a practic...More

Why does Ada compiler let range violations pass? It does give warning, but why does it let it pass if it is an error in any case? Is there a practical scenario in which this is a useful behaviour?

And most importantly: Why is type declaration a runtime entity? I mean the 3rd line of the code example is something I expect to be evaluated ahead of time. I thought that only the 5th line will "make it" into the executable. Why not? Is that something useful? Am I missing or misinterpreting something here?

with Ada.Text_IO;
procedure question is
    subtype Test is Natural range -1 .. 10;
begin
    Ada.Text_IO.Put_Line ("foobar");
end;

Note: Result is identical with "type Test is new Natural range -1..10;"

Note: GNAT 4.6

I have installed GNAT 4.3 from here

And added the following to my ....More

I have installed GNAT 4.3 from here

And added the following to my .bash_profile:

export PATH=/usr/local/ada-4.3/bin:$PATH

Now I can run gnatmake hello.adb

For the file hello.adb with the following contents:

with Ada.Text_IO;use Ada.Text_IO;
procedure Hello is
begin
    Put_Line ("Hello world!");
end Hello;

But I get this error:

gcc -c hello.adb

gcc: error trying to exec 'as': execvp: No such file or directory

gnatmake: "hello.adb" compilation error

I'm guessing there is a problem with my GNAT installation, but I have been unable to find a solution for this problem.

Thanks in advance for any suggestions.

If I understand correctly then the release mode enables a program to run faster than running the program in debug mode.

A general question ...More

If I understand correctly then the release mode enables a program to run faster than running the program in debug mode.

A general question will be if one has to run the program first in debug mode and then switch to run the program in release mode in order for the release mode to "skip over" checks it normally makes when running in debug mode? Or is one able to run directly a program in release mode right at the start?

Now when it comes to AdaGide, I see the option debug mode and release mode under Compile. Is placing a check mark next to release mode is all that's required to have AdaGide run the program in release mode? I'm using the GNAT GPL compiler.

Thanks a lot...

I'm trying to build gcc for use with an AVR micro controller and avr-ada, and I've hit a roadblock caused by my regular compiler being too picky abo...More

I'm trying to build gcc for use with an AVR micro controller and avr-ada, and I've hit a roadblock caused by my regular compiler being too picky about the version I needed for the AVR. I get the following warning, which in turn causes the gcc or make to report an error:

gcc -c -g -O2 -gnatpg -gnata -nostdinc -I- -I. -Iada 
  -I../../gcc/ada ../../gcc/ada/exp_ch5.adb -o ada/exp_ch5.o
exp_ch5.adb:177:16: warning: function "Has_Address_Clause" is not referenced
make[2]: *** [ada/exp_ch5.o] Error 1
make[1]: *** [all-gcc] Error 2
make: *** [all] Error 2

Is there a way to instruct gcc or make to not fail on warnings?