Re: [Dev-C++] Dev-C++ Users Beware!

[Abhijit S. <mu...@gm...>]

Quote Microsoft: "This isn't a bug, it's a feature." Seriously, though, =
this is one feature of the GCC compiler (I remember reading about it in =
the DJGPP docs). If you're still looking for the compiler to stop when =
it encounters non-ANSI code, there must be a command-line options =
somewhere.  Yup, here it is... from the Dev-C++ help file.

-------------------------------------------------------------------------=
-------

- Support all ANSI C standard programs (compiler parameter : -ansi):

This turns off certain features of GNU C that are incompatible with ANSI =
C, such as the asm, inline and typeof keywords, and predefined macros =
such as unix and vax that identify the type of system you are using.  It =
also enables the undesirable and rarely used ANSI trigraph feature, and =
it disables recognition of C++ style // comments.

-------------------------------------------------------------------------=
-------

But what the hell, GCC is kind of a standard in itself.
mdeth O
m.o.t.o[P.S.Y.C.H.O]=20

http://mudeth.tripod.com | ibr...@bi... | mu...@gm...
----- Original Message -----=20
  From: Bob Wilson=20
  To: Dev-C++ User Mailing List=20
  Sent: Saturday, April 20, 2002 3:29 AM
  Subject: [Dev-C++] Dev-C++ Users Beware!


  David,
    An array is not dynamic, the value you pass it at initalization must =
be a constat of some sort.if 'i' were to change during the program some =
weird voodoo (the program will crash,the world will end,etc.) all this =
will hapen because it cannot change the size of an array at =
runtime(reason no. 1 linked lists were created)
  I am in the process of learning C++, as Ioannis well knows, and a week =
or so ago I was working on the array chapter. In the past I have done =
most of my programming in pascal, and every pascal compiler I have used =
will not compile an array if the size of the array is a variable, i.e., =
no dynamic arrays. Just fooling around I modified the simple little C++ =
array program to define an array with a variable. I had not done any =
research but was confident that the compiler would flag an error and =
bail out.=20

  Not So! the program compiled and ran allowing me to change the size of =
the array. I tested the bounds of the program and could build quite =
large arrays. the size_of function always returnd the correct size of =
the array. I was really surprised because that it worked. I have not =
employed the technique in any real world program, because I felt that it =
would be much safer with pointers and linked lists.=20

  Your message above confirmed what I suspected but had not taken the =
time to investigate. Stroustrup says:
    The number of elements of the array, the array bound, must be a =
constant expresseion (=A7C.5)
  Paragraph C.5 says in part:
    A constant expression evaluates to an integral of enumeration =
constant. Such an expression is composed of literals, enumerators, and =
const initialized by constant expressions. < . . . > Intuitively, =
constant expressions are simple expressions that can be evaluated by the =
compiler before the program is linked and starts to run.
  That tells me that the compiler should have caught this and bailed out =
rather than compiling, linking, and running this program:=20

    #include <iostream.h>
    #include <stdlib.h>

    int main
    {
        int arraySize =3D 1;
        std::cout << "Enter the size of the array: ";
        std::cin >> arraySize;
        if (!(arraySize > 0))
        {
            system("pause");
            return 0;
        }
        int myArray[arraySize];
        int arrayLength =3D sizeof(myArray)/sizeof(myArray[0]);
        for (int i=3D0; i < arrayLength; i++)     // 0 to arrayLength-1
        {
            myArray[i] =3D (i + 1) * 2 + 1;
        }
        for (int i=3D0; i< arrayLength; i++)     // 0 to arrayLength-1
        {
            std::cout << i << ": " << myArray[i] << "\n";
        }
       =20
        system("pause");
        return 0;
    }
  The faulty compiler is the one used by Bloodshed. Visual C++ 6.0 =
caught the error. That is the second and most serious problem I have =
found with the compiler used by the dev-c++ environment. It appears it =
will properly compile ANSI standard code, but it will also compile code =
that is clearly outside of the standard.=20

  I believe that the dev-c++ compiler is the mingw compiler.=20

  Regards,

  Bob Wilson