Erroneous results with LOG function when using inline option (-gnatN)

[frederic.ormancey@atosorigin.com (Fr?d?ric Ormancey)]

Hello,

When compiling a simple program using Log function, instance from
Ada.Numerics.Generic_Elementary_Functions, I had an erroneous result
when using -gnatN option ( INLINE ).

Using ASM & Source debug with GVD to compare the code generation with
and without -gnatN option, it seems that the INLINE suppress too much
usefull code ...

Source code causing problem :
with Ada, Ada.Numerics, Ada.Numerics.Generic_Elementary_Functions;
with Text_Io;  use Text_Io;

procedure Test_Numeric is

    package Math is new Ada.Numerics.Generic_Elementary_Functions
(Long_Float);
    use Math;

    Taille_Table : Integer := 3534;
    Rang     : Integer := Taille_Table;
    Deux     : constant Integer := 2;
    Rnbval   : Long_Float;
    R,P,Q,D  : Integer := 0;
    T        : Integer := 0;
begin
    Rnbval := Long_Float(Taille_Table); 
    Put_Line(Long_Float'IMAGE(Rnbval));
    Put_Line(Long_Float'IMAGE(Log(Rnbval)));
    Put_Line(Long_Float'IMAGE(Log(2.0)));
    Put_Line(Long_Float'IMAGE(Log(Rnbval)/Log(2.0)));
    T      := Integer(Log(Rnbval)/Log(2.0)) -1;
    Put_Line(Integer'IMAGE(T));
end Test_Numeric;

correct result is :
 3.53400000000000E+03
 8.17018565287964E+00
 6.93147180559945E-01
 1.17870863245516E+01
 11

When using -gnatN option I got this erroneous result :
 3.53400000000000E+03
0.E+14
3.53400000053248E+14
5.04315471466814E-4932
 2147483647

The platform is Linux RedHat 7.2, with GNAT 3.15p. 
Same code compiled with Win2000 GNAT 3.15p seems to be good.

Thanks helping me to find if I made a programation error, or if it is
a bug in compiler.