"too few element" in an unconstrained array, given as litteral ?

[Mehdi Saada <00120260a@gmail.com>]

The definitions for polynoms I slightly modified, don't fit anymore wit the test program:

 28   Set(Poly3,(2/1, 5/8)); -- but every call on Set does the same
ts_poly1.adb:28:14: warning: too few elements for type "T_Liste_Coef" defined at p_poly_v1_g.ads:48, instance at line 20
ts_poly1.adb:28:14: warning: "Constraint_Error" will be raised at run time

 18    package PRat is new P_Rationnels_G(T_Entier);                        
 19    package PRatIO is new PRat.IO;                                       
 20    package PPoly is new P_Poly_V1_G(PRat, PRatIO, 40);               
_____________________________________
generic
   with package P_Rationnels is new P_Rationnels_G(<>);
   with package P_Rationnels_io is new P_Rationnels.Io(<>);
   Max : Positive;
package PPoly is
_____________________________________

subtype T_Degre is T_Entier range 0..T_Entier(Max); -- I found this phrasing ugly as hell, but I don't know how to make T_Entier visible in the "generic" part since p_rationnels is yet to be instanciated... But I guess it's not the cause of the exception here.

In the test program: Set(Poly3,(2/11)); -- any call of Set raises constraint_error

The current definitions:
type T_Liste_Coef is array (T_Degre range 1..T_Degre'Last) of T_Rationnel;
type T_Vect_Coef is array (T_Degre range <>) of T_Rationnel;
type T_Polynome (Degre : T_Degre := 0) is -- type mutant
record
   Coef : T_Vect_Coef (0..Degre) := (others => Nulle);
end record;

And the constructor method: :
procedure Set (
         Poly :    out T_Polynome;
         Vect : in     T_Liste_Coef ) is
      V_Coef : T_Vect_Coef (0 .. Vect'Last - 1);
   begin
      for I in Vect'range loop
      V_Coef (I - 1) := Vect (I);
   end loop;
   Poly := (Vect'Length - 1, V_Coef);
end Set;

How can an object of an UNCONSTAINED array type, given as a litteral, have "too few elements ?", though sometime I saw "too few" means "too much", but it wouldn't make more sense to me either.