Re: String Pointer Bug

[Per Sandberg <per.sandberg@bredband.net>]

Running GNAT Pro 5.03w (20041005-34)/ gcc-3.4.3  i get exactly the same 
messages as "compiler"

/Per


skidmarks wrote:

>(Program below): The same code fragment was run on two different
>compilers, GNAT and another commercial vendor, 'compiler. The results
>are inconsistent and I don't believe that both sets of errors can be
>correct. Before I scream and holler, I wonder if there are wiser heads
>who can provide insight into which (if any) compiler version is
>incorrect.
>
>The summary is that a pointer to a definite type and a pointer to an
>indefinite typed value have different constraints, detected and
>reported. I would assume that compliant compilers would complain
>similarly.
>
>Thanks
>
>art
>------------------------------ C O D E ------------------------------
>
>procedure Bug is
>
>  type String_Ptr     is access all String;
>
>  subtype Str_Ptr     is String_Ptr( 1 .. 12 );
>  
>  type String_Array   is array( 1 .. 68 ) of aliased String( 1 .. 12
>);
>  
>  Input         : String_Array := ( others => (others => ' ') );
>  StrArray      : array( 1 .. 68 ) of aliased String( 1 .. 12 );
>  Strng         : aliased String            := "one two three";
>  --      GNAT warning not issued by Compiler
>  --      >>> warning: aliased object has explicit bounds
>  --      >>> warning: declare without bounds (and with explicit
>initialization)
>  --      >>> warning: for use with unconstrained access
>  Str           : String_Ptr;
>  Str_Def       : Str_Ptr;
>
>  -- Compiler Diagnostic Message
>  -- LRM:3.10.2(27) The nominal subtype of the prefix to 'ACCESS or
>  --                'UNCHECKED_ACCESS must either statically match
>  --                the expected type or the designated subtype must
>be
>  --                discriminated and unconstrained
>
>  -- GNAT (gcc-3.3.1 & gcc-3.3.3)
>  -- object subtype must statically match designated subtype
>
>  --                                   Error Messages (See above)
>begin -- Bug                          GNAT   COMPILER
>   Str      := Input(1)'Access;     --  X      X
>   Str      := StrArray(1)'Access;  --  X      X
>   Str      := Strng'Access;
>   
>   Str_Def  := Input(1)'Access;     --         X
>   Str_Def  := StrArray(1)'Access;  --         X
>   Str_Def  := Strng'Access;        --  X
>end Bug;
>_______________________________________________
>comp.lang.ada mailing list
>comp.lang.ada@ada-france.org
>http://www.ada-france.org/mailman/listinfo/comp.lang.ada
>
>  
>