------- Comment #5 from fxcoudert at gcc dot gnu dot org 2007-10-01 23:28
-------
Hum, the real(16) case looks like loads of fun to come!
$ cat k.f90
integer, parameter :: k = 16
character(80) :: buf
real(k) :: xk, yk
xk = 1.0_k - epsilon(xk)
write (buf,'(1PG60.40)') xk
read (buf,*) yk
write (*,'(1PG60.40)') xk
write (*,'(1PG60.40)') yk
if (xk /= yk) print *, "Mismatch"
print *
xk = 1.0_k + epsilon(xk)
write (buf,'(1PG60.40)') xk
read (buf,*) yk
write (*,'(1PG60.40)') xk
write (*,'(1PG60.40)') yk
if (xk /= yk) print *, "Mismatch"
print *
end
$ gfortran k.f90 && ./a.out
1.9999999999999999999999999999999753481000
4.9303806576313237838233035330174139355000E-32
Mismatch
1.0000000000000000000000000000000246519000
1.0000000000000000000000000000000246519000
(Also, in the case of real(16), you need to add an E4 to the format anyway.)
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33469
