[Bug fortran/15809] ICE Using Pointer Functions

["sven dot buijssen at math dot uni-dortmund dot de" <gcc-bugzilla@gcc.gnu.org>]

------- Comment #15 from sven dot buijssen at math dot uni-dortmund dot de  2005-11-21 18:06 -------
I cannot tell why, but it seems to me that Paul Thomas' test case is no valid
code:

* Compaq Fortran Compiler X5.4A-1684-46B5P gives:
f90: Warning: line 14: An explicit-shaped array is being passed to a routine
that expects a pointer or assumed-shape array
  call a (ptr)
----------^

Ok, that's because of the spare dummy argument l in the subroutine definition.
Omitting it, Compaq compiles, decides that p is associated, but prints an empty
string.

* Same behaviour with g95 (Nov 12 2005): empty string

* Next compiler: Sun Fortran 95 8.1 Patch 117834-03 2005/06/15
The Sun Compiler totally refuses to compile Paul Thomas' test case (but
omitting the spare dummy argument l):

  call a (ptr)
  ^
Line = 14, Column = 3: ERROR: Procedure "A" is defined at line 1.  It must have
an explicit interface specified.

f90comp: 16 SOURCE LINES
f90comp: 1 ERRORS, 0 WARNINGS, 0 OTHER MESSAGES, 0 ANSI

* Rewriting the code to something equivalent

program demo

  character(8), dimension (:), pointer :: ptr
  character(8), dimension (2), target :: tar
  tar = "def"
  ptr => tar
  call a (ptr)
  if (associated (ptr)) print *, "in MAIN, ptr = ", ptr

contains
  subroutine a(p)
    character(8), dimension(:), pointer :: p
    if (associated (p)) then
      print *, p
    else
      print *, "not associated"
    end if
  end subroutine a

end program demo

solves all problems. g95, gfortran (20051113), ifort 9.0, Sun + Compaq Compiler
smoothly compile and print to screen the desired:

 def     def
 in MAIN, ptr = def     def


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15809