Problem with gfortran while developing a recursive function
which allocates an array stored in a derived-type.
This is the sample test :
module testmod
#define _DYNAMIC_TYPE allocatable
!#define _DYNAMIC_TYPE pointer
type, public :: t_type
integer, dimension(:), _DYNAMIC_TYPE :: chars
end type t_type
integer, save :: callnb = 0
contains
recursive function recursivefunc ( this ) result ( match )
type(t_type), intent(in) :: this
type(t_type) :: subpattern
logical :: thisalloc
integer :: thislength
logical :: match
write ( * , * ) "recursivefunc [" , callnb , "]"
thislength = size ( this % chars )
write ( * , * ) "length :", thislength
callnb = callnb + 1
thisalloc = allocated ( this % chars )
! thisalloc = associated ( this % chars )
if ( .NOT. thisalloc ) then
write ( 6 , * ) "STOP with error !"
stop
endif
if ( thislength == 0 ) then
match = .true.
return
endif
allocate ( subpattern % chars ( thislength - 1 ) )
match = recursivefunc ( subpattern )
end function recursivefunc
end module testmod
program testprog
use testmod
implicit none
type(t_type) :: this
logical :: match
allocate ( this % chars ( 10 ))
match = recursivefunc ( this )
print * , "match :", match
end program testprog
Compile it with :
gfortran -x f95-cpp-input testZeroSizeRecursive2.f90 -o
testZeroSizeRecursive2.exe
(flibs-workbench) 60 % testZeroSizeRecursive2.exe
recursivefunc [ 0 ]
length : 10
recursivefunc [ 1 ]
length : 9
STOP with error !
This is because the allocated statement return .false., even
if the array is really allocated.
Trying the "pointer" version by modifying the #define preprocessing statement
and the "allocated" to associated" make the problem disappear :
recursivefunc [ 0 ]
length : 10
recursivefunc [ 1 ]
length : 9
recursivefunc [ 2 ]
length : 8
recursivefunc [ 3 ]
length : 7
recursivefunc [ 4 ]
length : 6
recursivefunc [ 5 ]
length : 5
recursivefunc [ 6 ]
length : 4
recursivefunc [ 7 ]
length : 3
recursivefunc [ 8 ]
length : 2
recursivefunc [ 9 ]
length : 1
recursivefunc [ 10 ]
length : 0
match : T
This is the version of gfortran I currently use ( I downloaded it today
and I think that it is up-todate ) :
(flibs-workbench) 61 % gfortran -v
Using built-in specs.
Target: i586-pc-mingw32
Configured with: ../trunk/configure --prefix=/mingw
--enable-languages=c,fortran --with-gmp=/home/FX/local
--with-ld=/mingw/bin/ld --with-as=/mingw/bin/as --disable-werror
--enable-bootstrap --enable-threads --disable-nls
--build=i586-pc-mingw32 --enable-libgomp --disable-shared
Thread model: win32
gcc version 4.4.0 20080312 (experimental) [trunk revision 133139] (GCC)
Regards,
Michaël Baudin
--
Summary: Recursive function with allocatable array
Product: gcc
Version: 4.4.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: michael dot baudin at gmail dot com
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35959
