[Bug fortran/64104] [F2003][IEEE] Allow IEEE functions in specification expressions

[fxcoudert at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64104

--- Comment #3 from Francois-Xavier Coudert <fxcoudert at gcc dot gnu.org> ---
According to F08/0104 interp/erratum
(http://j3-fortran.org/doc/year/14/14-192.txt):

Allowed in constant expressions:

"(8) a reference to a transformational function from the intrinsic module
IEEE_ARITHMETIC or IEEE_EXCEPTIONS (14), where each argument is a constant
expression,"

which means:
IEEE_SELECTED_REAL_KIND
IEEE_SUPPORT_ROUNDING
IEEE_SUPPORT_FLAG
IEEE_SUPPORT_HALTING


Allowed in specification expressions:

"(nn) a reference to a transformational function from the intrinsic module
IEEE_ARITHMETIC or IEEE_EXCEPTIONS (14) or the intrinsic module ISO_C_BINDING
(15.2), where each argument is a restricted expression,"

which means:
IEEE_SELECTED_REAL_KIND
IEEE_SUPPORT_ROUNDING
IEEE_SUPPORT_FLAG
IEEE_SUPPORT_HALTING

and:

"(9) a specification inquiry, i.e.
  [...]
  (3) an inquiry function from the intrinsic modules IEEE_ARITHMETIC and
IEEE_EXCEPTIONS"

which means:

IEEE SUPPORT DATATYPE
IEEE SUPPORT DENORMAL
IEEE SUPPORT DIVIDE
IEEE SUPPORT INF
IEEE SUPPORT IO
IEEE SUPPORT NAN
IEEE SUPPORT SQRT
IEEE SUPPORT STANDARD
IEEE SUPPORT UNDERFLOW CONTROL