gfortran45 IEEE exceptions are in the manual, but not supported?

[Anton Shterenlikht]

On ia64 FreeBSD 9.0-current:

% cat tmp.f90 
program z
implicit none

real(kind=4) :: x,y

x=1.0e-30

y= x*x
write(*,*)y

y= 1.0/x/x
write(*,*)y

end program z

% gfortran45 -ffpe-trap=invalid,zero,overflow,underflow,precision,denormal tmp.f90

This program triggers over- and underflow.

% ./a.out
Fortran runtime warning: IEEE 'invalid operation' exception not supported.
Fortran runtime warning: IEEE 'denormal number' exception not supported.
Fortran runtime warning: IEEE 'division by zero' exception not supported.
Fortran runtime warning: IEEE 'overflow' exception not supported.
Fortran runtime warning: IEEE 'underflow' exception not supported.
Fortran runtime warning: IEEE 'loss of precision' exception not supported.
   0.0000000    
       +Infinity
% 

>From the man page:

       -ffpe-trap=list
           Specify a list of IEEE exceptions when a Floating Point Exception
           (FPE) should be raised.  On most systems, this will result in a
           SIGFPE signal being sent and the program being interrupted,
           producing a core file useful for debugging.  list is a (possibly
           empty) comma-separated list of the following IEEE exceptions:
           invalid (invalid floating point operation, such as "SQRT(-1.0)"),
           zero (division by zero), overflow (overflow in a floating point
           operation), underflow (underflow in a floating point operation),
           precision (loss of precision during operation) and denormal
           (operation produced a denormal value).


I understand that IEEE fpe are not implemented yet in gfortran.
Should then the reference to -ffpe-trap be removed from
the man page?

Many thanks
Anton


-- 
Anton Shterenlikht
Room 2.6, Queen's Building
Mech Eng Dept
Bristol University
University Walk, Bristol BS8 1TR, UK
Tel: +44 (0)117 331 5944
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