See http://gcc.gnu.org/ml/fortran/2007-09/msg00301.html
for the initial bug report by Salvatore Filippone (thanks for finding the bug!)
and a longer example.
Assume the following code:
type double_vector_item
real(c_double), allocatable :: v(:)
end type double_vector_item
type(double_vector_item), target :: dbv_pool
While V(:) itself is does not have the TARGET attribut, dbv_pool%v has it due
to the following clause in the Fortran 2003 standard ("5.1.2.14 TARGET
attribute"):
"If an object has the TARGET attribute, then all of its nonpointer subobjects
also have the TARGET attribute."
Additionally, "real(c_double)" is of interoperable type and kind; thus the
following clause of "15.1.2.5 C LOC (X)" applies to dbv_pool%v:
"Argument. X shall [...] (1) have interoperable type and type parameters and be
[...] (b) an allocated allocatable variable that has the TARGET attribute and
is not an array of zero size".
I did not investigate in detail, but gfortran seems to fail (in resolve.c's
gfc_iso_c_func_interface) at
/* See if we have interoperable type and type param. */
if (verify_c_interop (&(args->expr->symtree->n.sym->ts),
args->expr->symtree->n.sym->name,
&(args->expr->where)) == SUCCESS
|| gfc_check_any_c_kind (&(args_sym->ts)) == SUCCESS)
Notes:
- dbv_pool itself is not C interoperable as it has no BIND(C) - at it cannot
have this attribute at V is allocatable.
- V cannot have an explicit TARGET attribute as it is a TYPE component
- sunf95 has the same problem as gfortran, but ifort 10, NAG f95 and g95 accept
this program.
--
Summary: Bind(C): C_LOC rejects interoperable arguments
Product: gcc
Version: 4.3.0
Status: UNCONFIRMED
Keywords: rejects-valid
Severity: normal
Priority: P3
Component: fortran
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: burnus at gcc dot gnu dot org
OtherBugsDependingO 32630
nThis:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33497
