On Monday 02 January 2012 12:20:36 Tobias Burnus wrote:
> Hello Mikael,
>
> Mikael Morin wrote:
> > Regression tested on x86_64-unknown-linux-gnu. OK for 4.7/4.6/4.5[/4.4] ?
>
> OK - thanks for the comprehensive patch explanation and for the patch
> itself.
>
> > + else
> > + {
> > + /* Otherwise, evaluate the argument out of the loop and pass
> > + a reference to the value. */
> > + gfc_conv_expr (&se, expr);
>
> s/out of/outside/
Fixed
>
> > + if (dummy_arg != NULL
> > + && dummy_arg->sym->attr.optional
> > + && arg->expr
I removed that one as it is guarded by:
if (!arg->expr)
continue;
> > + && arg->expr->symtree
> > + && arg->expr->symtree->n.sym->attr.optional
> > + && arg->expr->ref == NULL)
> > + newss->info->data.scalar.can_be_null_ref = true;
>
> I wonder whether one needs to take special care for the following
> Fortran 2008 feature: "A null pointer can be used to denote an absent
> nonallocatable nonpoin-
> ter optional argument." - I guess, one doesn't.
>
I think there is an issue. I will look at it separately.
Mikael
Index: fortran/trans-expr.c
===================================================================
--- fortran/trans-expr.c (révision 182873)
+++ fortran/trans-expr.c (révision 182874)
@@ -5331,6 +5331,11 @@ gfc_conv_expr (gfc_se * se, gfc_expr * expr)
/* Substitute a scalar expression evaluated outside the scalarization
loop. */
se->expr = ss_info->data.scalar.value;
+ /* If the reference can be NULL, the value field contains the reference,
+ not the value the reference points to (see gfc_add_loop_ss_code). */
+ if (ss_info->data.scalar.can_be_null_ref)
+ se->expr = build_fold_indirect_ref_loc (input_location, se->expr);
+
se->string_length = ss_info->string_length;
gfc_advance_se_ss_chain (se);
return;
Index: fortran/trans-array.c
===================================================================
--- fortran/trans-array.c (révision 182873)
+++ fortran/trans-array.c (révision 182874)
@@ -2422,10 +2422,21 @@ gfc_add_loop_ss_code (gfc_loopinfo * loop, gfc_ss
break;
case GFC_SS_REFERENCE:
- /* Scalar argument to elemental procedure. Evaluate this
- now. */
+ /* Scalar argument to elemental procedure. */
gfc_init_se (&se, NULL);
- gfc_conv_expr (&se, expr);
+ if (ss_info->data.scalar.can_be_null_ref)
+ {
+ /* If the actual argument can be absent (in other words, it can
+ be a NULL reference), don't try to evaluate it; pass instead
+ the reference directly. */
+ gfc_conv_expr_reference (&se, expr);
+ }
+ else
+ {
+ /* Otherwise, evaluate the argument outside the loop and pass
+ a reference to the value. */
+ gfc_conv_expr (&se, expr);
+ }
gfc_add_block_to_block (&outer_loop->pre, &se.pre);
gfc_add_block_to_block (&outer_loop->post, &se.post);
if (gfc_is_class_scalar_expr (expr))
Index: fortran/ChangeLog
===================================================================
--- fortran/ChangeLog (révision 182873)
+++ fortran/ChangeLog (révision 182874)
@@ -1,5 +1,14 @@
2012-01-04 Mikael Morin <mik...@gcc.gnu.org>
+ PR fortran/50981
+ * trans.h (struct gfc_ss_info): New field data::scalar::can_be_null_ref
+ * trans-array.c: If the reference can be NULL, save the reference
+ instead of the value.
+ * trans-expr.c (gfc_conv_expr): If we have saved a reference,
+ dereference it.
+
+2012-01-04 Mikael Morin <mik...@gcc.gnu.org>
+
* trans-expr.c (gfc_conv_expr): Move address taking...
(gfc_conv_expr_reference): ... here.
Index: fortran/trans.h
===================================================================
--- fortran/trans.h (révision 182873)
+++ fortran/trans.h (révision 182874)
@@ -145,8 +145,9 @@ typedef enum
GFC_SS_SCALAR,
/* Like GFC_SS_SCALAR it evaluates the expression outside the
- loop. Is always evaluated as a reference to the temporary.
- Used for elemental function arguments. */
+ loop. Is always evaluated as a reference to the temporary, unless
+ temporary evaluation can result in a NULL pointer dereferencing (case of
+ optional arguments). Used for elemental function arguments. */
GFC_SS_REFERENCE,
/* An array section. Scalarization indices will be substituted during
@@ -196,6 +197,9 @@ typedef struct gfc_ss_info
struct
{
tree value;
+ /* Tells whether the reference can be null in the GFC_SS_REFERENCE case.
+ Used to handle elemental procedures' optional arguments. */
+ bool can_be_null_ref;
}
scalar;
Index: testsuite/gfortran.dg/elemental_optional_args_2.f90
===================================================================
--- testsuite/gfortran.dg/elemental_optional_args_2.f90 (révision 0)
+++ testsuite/gfortran.dg/elemental_optional_args_2.f90 (révision 182875)
@@ -0,0 +1,80 @@
+! { dg-do run }
+!
+! PR fortran/50981
+! The program used to dereference a NULL pointer when trying to access
+! an optional dummy argument to be passed to an elemental subprocedure.
+!
+! Original testcase from Andriy Kostyuk <kost...@fias.uni-frankfurt.de>
+
+PROGRAM test
+ IMPLICIT NONE
+ REAL(KIND=8), DIMENSION(2) :: aa, rr
+
+ aa(1)=10.
+ aa(2)=11.
+
+
+ ! WRITE(*,*) 'Both f1 and ff work if the optional parameter is present:'
+
+ rr=f1(aa,1)
+ ! WRITE(*,*) ' rr(1)=', rr(1), ' rr(2)=', rr(2)
+ IF (ANY(rr /= (/ 110, 132 /))) CALL ABORT
+
+ rr=0
+ rr=ff(aa,1)
+ ! WRITE(*,*) ' rr(1)=', rr(1), ' rr(2)=', rr(2)
+ IF (ANY(rr /= (/ 110, 132 /))) CALL ABORT
+
+
+ ! WRITE(*,*) 'But only f1 works if the optional parameter is absent:'
+
+ rr=0
+ rr=f1(aa)
+ ! WRITE(*,*) ' rr(1)=', rr(1), ' rr(2)=', rr(2)
+ IF (ANY(rr /= (/ 110, 132 /))) CALL ABORT
+
+ rr = 0
+ rr=ff(aa)
+ ! WRITE(*,*) ' rr(1)=', rr(1), ' rr(2)=', rr(2)
+ IF (ANY(rr /= (/ 110, 132 /))) CALL ABORT
+
+
+CONTAINS
+
+ ELEMENTAL REAL(KIND=8) FUNCTION ff(a,b)
+ IMPLICIT NONE
+ REAL(KIND=8), INTENT(IN) :: a
+ INTEGER, INTENT(IN), OPTIONAL :: b
+ REAL(KIND=8), DIMENSION(2) :: ac
+ ac(1)=a
+ ac(2)=a**2
+ ff=SUM(gg(ac,b))
+ END FUNCTION ff
+
+ ELEMENTAL REAL(KIND=8) FUNCTION f1(a,b)
+ IMPLICIT NONE
+ REAL(KIND=8), INTENT(IN) :: a
+ INTEGER, INTENT(IN), OPTIONAL :: b
+ REAL(KIND=8), DIMENSION(2) :: ac
+ ac(1)=a
+ ac(2)=a**2
+ f1=gg(ac(1),b)+gg(ac(2),b) ! This is the same as in ff, but without using the elemental feature of gg
+ END FUNCTION f1
+
+ ELEMENTAL REAL(KIND=8) FUNCTION gg(a,b)
+ IMPLICIT NONE
+ REAL(KIND=8), INTENT(IN) :: a
+ INTEGER, INTENT(IN), OPTIONAL :: b
+ INTEGER ::b1
+ IF(PRESENT(b)) THEN
+ b1=b
+ ELSE
+ b1=1
+ ENDIF
+ gg=a**b1
+ END FUNCTION gg
+
+
+END PROGRAM test
+
+
Index: testsuite/ChangeLog
===================================================================
--- testsuite/ChangeLog (révision 182874)
+++ testsuite/ChangeLog (révision 182875)
@@ -1,3 +1,7 @@
+2012-01-04 Mikael Morin <mik...@gcc.gnu.org>
+
+ * gfortran.dg/elemental_optional_args_2.f90: New test.
+
2012-01-04 Thomas Koenig <tkoe...@gcc.gnu.org>
PR fortran/49693
Index: fortran/trans-array.c
===================================================================
--- fortran/trans-array.c (révision 182874)
+++ fortran/trans-array.c (révision 182875)
@@ -8307,12 +8307,16 @@ gfc_reverse_ss (gfc_ss * ss)
}
-/* Walk the arguments of an elemental function. */
+/* Walk the arguments of an elemental function.
+ PROC_EXPR is used to check whether an argument is permitted to be absent. If
+ it is NULL, we don't do the check and the argument is assumed to be present.
+*/
gfc_ss *
gfc_walk_elemental_function_args (gfc_ss * ss, gfc_actual_arglist *arg,
- gfc_ss_type type)
+ gfc_expr *proc_expr, gfc_ss_type type)
{
+ gfc_formal_arglist *dummy_arg;
int scalar;
gfc_ss *head;
gfc_ss *tail;
@@ -8320,6 +8324,28 @@ gfc_walk_elemental_function_args (gfc_ss * ss, gfc
head = gfc_ss_terminator;
tail = NULL;
+
+ if (proc_expr)
+ {
+ gfc_ref *ref;
+
+ /* Normal procedure case. */
+ dummy_arg = proc_expr->symtree->n.sym->formal;
+
+ /* Typebound procedure case. */
+ for (ref = proc_expr->ref; ref; ref = ref->next)
+ {
+ if (ref->type == REF_COMPONENT
+ && ref->u.c.component->attr.proc_pointer
+ && ref->u.c.component->ts.interface)
+ dummy_arg = ref->u.c.component->ts.interface->formal;
+ else
+ dummy_arg = NULL;
+ }
+ }
+ else
+ dummy_arg = NULL;
+
scalar = 1;
for (; arg; arg = arg->next)
{
@@ -8333,6 +8359,13 @@ gfc_walk_elemental_function_args (gfc_ss * ss, gfc
gcc_assert (type == GFC_SS_SCALAR || type == GFC_SS_REFERENCE);
newss = gfc_get_scalar_ss (head, arg->expr);
newss->info->type = type;
+
+ if (dummy_arg != NULL
+ && dummy_arg->sym->attr.optional
+ && arg->expr->symtree
+ && arg->expr->symtree->n.sym->attr.optional
+ && arg->expr->ref == NULL)
+ newss->info->data.scalar.can_be_null_ref = true;
}
else
scalar = 0;
@@ -8344,6 +8377,9 @@ gfc_walk_elemental_function_args (gfc_ss * ss, gfc
while (tail->next != gfc_ss_terminator)
tail = tail->next;
}
+
+ if (dummy_arg != NULL)
+ dummy_arg = dummy_arg->next;
}
if (scalar)
@@ -8393,7 +8429,7 @@ gfc_walk_function_expr (gfc_ss * ss, gfc_expr * ex
by reference. */
if (sym->attr.elemental || (comp && comp->attr.elemental))
return gfc_walk_elemental_function_args (ss, expr->value.function.actual,
- GFC_SS_REFERENCE);
+ expr, GFC_SS_REFERENCE);
/* Scalar functions are OK as these are evaluated outside the scalarization
loop. Pass back and let the caller deal with it. */
Index: fortran/trans-array.h
===================================================================
--- fortran/trans-array.h (révision 182874)
+++ fortran/trans-array.h (révision 182875)
@@ -73,7 +73,7 @@ gfc_ss *gfc_walk_subexpr (gfc_ss *, gfc_expr *);
gfc_ss *gfc_walk_array_ref (gfc_ss *, gfc_expr *, gfc_ref * ref);
/* Walk the arguments of an elemental function. */
gfc_ss *gfc_walk_elemental_function_args (gfc_ss *, gfc_actual_arglist *,
- gfc_ss_type);
+ gfc_expr *, gfc_ss_type);
/* Walk an intrinsic function. */
gfc_ss *gfc_walk_intrinsic_function (gfc_ss *, gfc_expr *,
gfc_intrinsic_sym *);
Index: fortran/ChangeLog
===================================================================
--- fortran/ChangeLog (révision 182874)
+++ fortran/ChangeLog (révision 182875)
@@ -1,6 +1,17 @@
2012-01-04 Mikael Morin <mik...@gcc.gnu.org>
PR fortran/50981
+ * trans-array.h (gfc_walk_elemental_function_args): New argument.
+ * trans-intrinsic.c (gfc_walk_intrinsic_function): Update call.
+ * trans-stmt.c (gfc_trans_call): Ditto.
+ * trans-array.c (gfc_walk_function_expr): Ditto.
+ (gfc_walk_elemental_function_args): Get the dummy argument list
+ if possible. Check that the dummy and the actual argument are both
+ optional, and set can_be_null_ref accordingly.
+
+2012-01-04 Mikael Morin <mik...@gcc.gnu.org>
+
+ PR fortran/50981
* trans.h (struct gfc_ss_info): New field data::scalar::can_be_null_ref
* trans-array.c: If the reference can be NULL, save the reference
instead of the value.
Index: fortran/trans-stmt.c
===================================================================
--- fortran/trans-stmt.c (révision 182874)
+++ fortran/trans-stmt.c (révision 182875)
@@ -348,7 +348,8 @@ gfc_trans_call (gfc_code * code, bool dependency_c
ss = gfc_ss_terminator;
if (code->resolved_sym->attr.elemental)
- ss = gfc_walk_elemental_function_args (ss, code->ext.actual, GFC_SS_REFERENCE);
+ ss = gfc_walk_elemental_function_args (ss, code->ext.actual,
+ code->expr1, GFC_SS_REFERENCE);
/* Is not an elemental subroutine call with array valued arguments. */
if (ss == gfc_ss_terminator)
Index: fortran/trans-intrinsic.c
===================================================================
--- fortran/trans-intrinsic.c (révision 182874)
+++ fortran/trans-intrinsic.c (révision 182875)
@@ -7149,7 +7149,7 @@ gfc_walk_intrinsic_function (gfc_ss * ss, gfc_expr
if (isym->elemental)
return gfc_walk_elemental_function_args (ss, expr->value.function.actual,
- GFC_SS_SCALAR);
+ NULL, GFC_SS_SCALAR);
if (expr->rank == 0)
return ss;
