This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
[Patch, fortran] PR42309 - Problem with a pointer array passed to a subroutine
- From: Paul Richard Thomas <paul dot richard dot thomas at gmail dot com>
- To: fortran at gcc dot gnu dot org, gcc-patches <gcc-patches at gcc dot gnu dot org>
- Date: Wed, 3 Feb 2010 06:51:02 +0100
- Subject: [Patch, fortran] PR42309 - Problem with a pointer array passed to a subroutine
This is another one of our serious bugs and yet another that can only
be properly fixed by array descriptor reform. A dummy, pointer
argument is expected to have unity lbounds, with an appropriate
offset, and this patch makes it so. The fix has the advantage of
fixing, if not a corner case, certainly something quite unusual;
therefore, the likelihood of regression is small..... on geological
timescales.
Bootstrapped and regtested on FC9/x86_64 - OK for trunk and 4.4?
Paul
2010-02-03 Paul Thomas <pault@gcc.gnu.org>
PR fortran/42309
* trans-expr.c (gfc_conv_subref_array_arg): Add new argument
'formal_ptr'. If this is true, give returned descriptor unity
lbounds, in all dimensions, and the appropriate offset.
(gfc_conv_procedure_call); If formal is a pointer, set the last
argument of gfc_conv_subref_array_arg to true.
* trans.h : Add last argument for gfc_conv_subref_array_arg.
* trans-io.c (set_internal_unit, gfc_trans_transfer): Set the
new arg of gfc_conv_subref_array_arg to false.
* trans-stmt.c (forall_make_variable_temp): The same.
2010-02-03 Paul Thomas <pault@gcc.gnu.org>
PR fortran/42309
* gfortran.dg/subref_array_pointer_4.f90 : New test.
Index: gcc/fortran/trans-expr.c
===================================================================
*** gcc/fortran/trans-expr.c (revision 156460)
--- gcc/fortran/trans-expr.c (working copy)
*************** gfc_apply_interface_mapping (gfc_interfa
*** 2294,2301 ****
an actual argument derived type array is copied and then returned
after the function call. */
void
! gfc_conv_subref_array_arg (gfc_se * parmse, gfc_expr * expr,
! int g77, sym_intent intent)
{
gfc_se lse;
gfc_se rse;
--- 2294,2301 ----
an actual argument derived type array is copied and then returned
after the function call. */
void
! gfc_conv_subref_array_arg (gfc_se * parmse, gfc_expr * expr, int g77,
! sym_intent intent, bool formal_ptr)
{
gfc_se lse;
gfc_se rse;
*************** gfc_conv_subref_array_arg (gfc_se * parm
*** 2308,2313 ****
--- 2308,2314 ----
tree tmp_index;
tree tmp;
tree base_type;
+ tree size;
stmtblock_t body;
int n;
*************** gfc_conv_subref_array_arg (gfc_se * parm
*** 2501,2506 ****
--- 2502,2543 ----
if (expr->ts.type == BT_CHARACTER)
parmse->string_length = expr->ts.u.cl->backend_decl;
+ /* Determine the offset for pointer formal arguments ans set the
+ lbounds to one. */
+ if (formal_ptr)
+ {
+ size = gfc_index_one_node;
+ offset = gfc_index_zero_node;
+ for (n = 0; n < info->dimen; n++)
+ {
+ tmp = gfc_conv_descriptor_ubound_get (parmse->expr,
+ gfc_rank_cst[n]);
+ tmp = fold_build2 (PLUS_EXPR, gfc_array_index_type,
+ tmp, gfc_index_one_node);
+ gfc_conv_descriptor_ubound_set (&parmse->pre,
+ parmse->expr,
+ gfc_rank_cst[n],
+ tmp);
+ gfc_conv_descriptor_lbound_set (&parmse->pre,
+ parmse->expr,
+ gfc_rank_cst[n],
+ gfc_index_one_node);
+ size = gfc_evaluate_now (size, &parmse->pre);
+ offset = fold_build2 (MINUS_EXPR, gfc_array_index_type,
+ offset, size);
+ offset = gfc_evaluate_now (offset, &parmse->pre);
+ tmp = fold_build2 (MINUS_EXPR, gfc_array_index_type,
+ rse.loop->to[n], rse.loop->from[n]);
+ tmp = fold_build2 (PLUS_EXPR, gfc_array_index_type,
+ tmp, gfc_index_one_node);
+ size = fold_build2 (MULT_EXPR, gfc_array_index_type,
+ size, tmp);
+ }
+
+ gfc_conv_descriptor_offset_set (&parmse->pre, parmse->expr,
+ offset);
+ }
+
/* We want either the address for the data or the address of the descriptor,
depending on the mode of passing array arguments. */
if (g77)
*************** gfc_conv_procedure_call (gfc_se * se, gf
*** 3005,3011 ****
is converted to a temporary, which is passed and then
written back after the procedure call. */
gfc_conv_subref_array_arg (&parmse, e, f,
! fsym ? fsym->attr.intent : INTENT_INOUT);
else
gfc_conv_array_parameter (&parmse, e, argss, f, fsym,
sym->name, NULL);
--- 3042,3049 ----
is converted to a temporary, which is passed and then
written back after the procedure call. */
gfc_conv_subref_array_arg (&parmse, e, f,
! fsym ? fsym->attr.intent : INTENT_INOUT,
! fsym && fsym->attr.pointer);
else
gfc_conv_array_parameter (&parmse, e, argss, f, fsym,
sym->name, NULL);
Index: gcc/fortran/trans.h
===================================================================
*** gcc/fortran/trans.h (revision 156460)
--- gcc/fortran/trans.h (working copy)
*************** int gfc_is_intrinsic_libcall (gfc_expr *
*** 315,321 ****
int gfc_conv_procedure_call (gfc_se *, gfc_symbol *, gfc_actual_arglist *,
gfc_expr *, tree);
! void gfc_conv_subref_array_arg (gfc_se *, gfc_expr *, int, sym_intent);
/* gfc_trans_* shouldn't call push/poplevel, use gfc_push/pop_scope */
--- 316,322 ----
int gfc_conv_procedure_call (gfc_se *, gfc_symbol *, gfc_actual_arglist *,
gfc_expr *, tree);
! void gfc_conv_subref_array_arg (gfc_se *, gfc_expr *, int, sym_intent, bool);
/* gfc_trans_* shouldn't call push/poplevel, use gfc_push/pop_scope */
Index: gcc/fortran/trans-io.c
===================================================================
*** gcc/fortran/trans-io.c (revision 156460)
--- gcc/fortran/trans-io.c (working copy)
*************** set_internal_unit (stmtblock_t * block,
*** 741,747 ****
/* Use a temporary for components of arrays of derived types
or substring array references. */
gfc_conv_subref_array_arg (&se, e, 0,
! last_dt == READ ? INTENT_IN : INTENT_OUT);
tmp = build_fold_indirect_ref_loc (input_location,
se.expr);
se.expr = gfc_build_addr_expr (pchar_type_node, tmp);
--- 741,747 ----
/* Use a temporary for components of arrays of derived types
or substring array references. */
gfc_conv_subref_array_arg (&se, e, 0,
! last_dt == READ ? INTENT_IN : INTENT_OUT, false);
tmp = build_fold_indirect_ref_loc (input_location,
se.expr);
se.expr = gfc_build_addr_expr (pchar_type_node, tmp);
*************** gfc_trans_transfer (gfc_code * code)
*** 2211,2217 ****
if (seen_vector && last_dt == READ)
{
/* Create a temp, read to that and copy it back. */
! gfc_conv_subref_array_arg (&se, expr, 0, INTENT_OUT);
tmp = se.expr;
}
else
--- 2211,2217 ----
if (seen_vector && last_dt == READ)
{
/* Create a temp, read to that and copy it back. */
! gfc_conv_subref_array_arg (&se, expr, 0, INTENT_OUT, false);
tmp = se.expr;
}
else
Index: gcc/fortran/trans-stmt.c
===================================================================
*** gcc/fortran/trans-stmt.c (revision 156460)
--- gcc/fortran/trans-stmt.c (working copy)
*************** forall_make_variable_temp (gfc_code *c,
*** 1800,1806 ****
if (old_sym->attr.dimension)
{
gfc_init_se (&tse, NULL);
! gfc_conv_subref_array_arg (&tse, e, 0, INTENT_IN);
gfc_add_block_to_block (pre, &tse.pre);
gfc_add_block_to_block (post, &tse.post);
tse.expr = build_fold_indirect_ref_loc (input_location, tse.expr);
--- 1800,1806 ----
if (old_sym->attr.dimension)
{
gfc_init_se (&tse, NULL);
! gfc_conv_subref_array_arg (&tse, e, 0, INTENT_IN, false);
gfc_add_block_to_block (pre, &tse.pre);
gfc_add_block_to_block (post, &tse.post);
tse.expr = build_fold_indirect_ref_loc (input_location, tse.expr);
Index: gcc/testsuite/gfortran.dg/subref_array_pointer_4.f90
===================================================================
*** gcc/testsuite/gfortran.dg/subref_array_pointer_4.f90 (revision 0)
--- gcc/testsuite/gfortran.dg/subref_array_pointer_4.f90 (revision 0)
***************
*** 0 ****
--- 1,27 ----
+ ! { dg-do run }
+ ! Tests the fix for PR42309, in which the indexing of 'Q'
+ ! was off by one.
+ !
+ ! Contributed by Gilbert Scott <gilbert.scott@easynet.co.uk>
+ !
+ PROGRAM X
+ TYPE T
+ INTEGER :: I
+ REAL :: X
+ END TYPE T
+ TYPE(T), TARGET :: T1(0:3)
+ INTEGER, POINTER :: P(:)
+ REAL :: SOURCE(4) = [10., 20., 30., 40.]
+
+ T1%I = [1, 2, 3, 4]
+ T1%X = SOURCE
+ P => T1%I
+ CALL Z(P)
+ IF (ANY (T1%I .NE. [999, 2, 999, 4])) CALL ABORT
+ IF (ANY (T1%X .NE. SOURCE)) CALL ABORT
+ CONTAINS
+ SUBROUTINE Z(Q)
+ INTEGER, POINTER :: Q(:)
+ Q(1:3:2) = 999
+ END SUBROUTINE Z
+ END PROGRAM X