http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47240
--- Comment #8 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2011-01-11 21:38:46 UTC --- (In reply to comment #7) > > ... > > ... this produces loads of regressions. > > ... but the following variant doesn't: > ... Confirmed, however the following code [macbook] f90/bug% cat pr35971_red.f90 module other_fun use ISO_C_BINDING implicit none private ! Message to be returned by procedure pointed to ! by the C_FUNPTR character, allocatable, save :: my_message(:) ! Interface block for the procedure pointed to ! by the C_FUNPTR public abstract_fun abstract interface function abstract_fun(x) use ISO_C_BINDING import my_message implicit none integer(C_INT) x(:) character(size(my_message),C_CHAR) abstract_fun(size(x)) end function abstract_fun end interface contains ! Procedure to store the message and get the C_FUNPTR function gp(message) bind(C,name='BlAh') ! procedure(abstract_fun) make_mess character(kind=C_CHAR) message(*) type(C_FUNPTR) gp integer(C_INT64_T) i i = 1 do while(message(i) /= C_NULL_CHAR) i = i+1 end do my_message = message(int(1,kind(i)):i-1) gp = get_funloc(make_mess,aux) ! gp = aux(make_mess) end function gp ! Intermediate procedure to pass the function and get ! back the C_FUNPTR function get_funloc(x,y) procedure(abstract_fun) x type(C_FUNPTR) y external y type(C_FUNPTR) get_funloc get_funloc = y(x) end function get_funloc ! Procedure to convert the function to C_FUNPTR function aux(x) interface subroutine x() bind(C) end subroutine x end interface type(C_FUNPTR) aux aux = C_FUNLOC(x) end function aux ! Procedure pointed to by the C_FUNPTR function make_mess(x) integer(C_INT) x(:) character(size(my_message),C_CHAR) make_mess(size(x)) make_mess = transfer(my_message,make_mess(1)) end function make_mess end module other_fun end gives at -O2 and above [macbook] f90/bug% gfc -O2 pr35971_red.f90 pr35971_red.f90: In function 'gp': pr35971_red.f90:67:0: error: non-trivial conversion at assignment void (*<T64>) (void) void (*<T49d>) (struct array1_unknown &, integer(kind=4), struct array1_integer(kind=4) & restrict) __result_gp_72 = make_mess; pr35971_red.f90:67:0: internal compiler error: verify_stmts failed