When using the transfer intrinsic to convert a character string to an array of
integers, and the string does not fit exactly into the integer array data
block, the resultant integer array is scope dependent, with the same code
giving a different resultant integer array in different subroutines/program
units. Basically, the transfer function is not deterministic in the case where
the source data is smaller than the destination data.
There is a small program below to demonstrate the issue. The integer array is
printed twice, and (on my machine) is different each time. The code producing
the two sets of output is exactly the same, but in the first case the code is
embedded in the main program, and in the other case in a subroutine.
I do not have a copy of the standard, but I cannot imagine that this behavior
is correct. The problem arises even if the destination array is initialized to
zero (as shown in the example).
module DataMod
type Byte
character(len=1) :: singleByte
end type
end module
subroutine sub()
use DataMod
integer :: i(1), intarray(4), j
character(len=15) :: str1
type (Byte) :: bytes(15)
type (Byte) :: byteProt(1)
bytes = transfer('123456789012345', byteProt)
print *, bytes(:)%singleByte
intarray = 0
intarray = transfer(bytes, i)
print *, intarray
end subroutine
program test
use DataMod
integer :: i(1), intarray(4), j
character(len=15) :: str1
type (Byte) :: bytes(15)
type (Byte) :: byteProt(1)
bytes = transfer('123456789012345', byteProt)
print *, bytes(:)%singleByte
intarray = 0
intarray = transfer(bytes, i)
print *, intarray
call sub()
end program
--
Summary: TRANSFER intrinsic is context sensitive
Product: gcc
Version: 4.3.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: drewmccormack at mac dot com
GCC build triplet: gcc version 4.3.0 20070511 (experimental)
GCC host triplet: powerpc-apple-darwin8.9.0
GCC target triplet: powerpc-apple-darwin8.9.0
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33037
