Dear all,
array bounds checking was missing a few cases of array sections
that are handled via gfc_conv_expr_descriptor. Bounds checking
was done for the dimensions with ranges, but not for elemental
dimensions.
The attached patch implements that and fixes pr30802 and also
pr97039, maybe a few more similar cases.
Regtested on x86_64-pc-linux-gnu. OK for mainline?
Thanks,
Harald
From bb2a765f56b440c8d086329f55c8ff0eaee2b97d Mon Sep 17 00:00:00 2001
From: Harald Anlauf
Date: Thu, 14 Sep 2023 22:08:26 +0200
Subject: [PATCH] Fortran: improve bounds-checking for array sections [PR30802]
gcc/fortran/ChangeLog:
PR fortran/30802
* trans-array.cc (trans_array_bound_check): Add optional argument
COMPNAME for explicit specification of array component name.
(array_bound_check_elemental): Helper function for generating
bounds-checking code for elemental dimensions.
(gfc_conv_expr_descriptor): Use bounds-checking also for elemental
dimensions, i.e. those not handled by the scalarizer.
gcc/testsuite/ChangeLog:
PR fortran/30802
* gfortran.dg/bounds_check_fail_6.f90: New test.
---
gcc/fortran/trans-array.cc| 72 ++-
.../gfortran.dg/bounds_check_fail_6.f90 | 29
2 files changed, 100 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gfortran.dg/bounds_check_fail_6.f90
diff --git a/gcc/fortran/trans-array.cc b/gcc/fortran/trans-array.cc
index 6ca58e98547..71123e37477 100644
--- a/gcc/fortran/trans-array.cc
+++ b/gcc/fortran/trans-array.cc
@@ -3452,7 +3452,8 @@ gfc_conv_array_ubound (tree descriptor, int dim)
static tree
trans_array_bound_check (gfc_se * se, gfc_ss *ss, tree index, int n,
- locus * where, bool check_upper)
+ locus * where, bool check_upper,
+ const char *compname = NULL)
{
tree fault;
tree tmp_lo, tmp_up;
@@ -3474,6 +3475,10 @@ trans_array_bound_check (gfc_se * se, gfc_ss *ss, tree index, int n,
if (VAR_P (descriptor))
name = IDENTIFIER_POINTER (DECL_NAME (descriptor));
+ /* Use given (array component) name. */
+ if (compname)
+name = compname;
+
/* If upper bound is present, include both bounds in the error message. */
if (check_upper)
{
@@ -3524,6 +3529,67 @@ trans_array_bound_check (gfc_se * se, gfc_ss *ss, tree index, int n,
}
+/* Generate code for bounds checking for elemental dimensions. */
+
+static void
+array_bound_check_elemental (gfc_se * se, gfc_ss * ss, gfc_expr * expr)
+{
+ gfc_array_ref *ar;
+ gfc_ref *ref;
+ gfc_symbol *sym;
+ char *var_name = NULL;
+ size_t len;
+ int dim;
+
+ if (!(gfc_option.rtcheck & GFC_RTCHECK_BOUNDS))
+return;
+
+ if (expr->expr_type == EXPR_VARIABLE)
+{
+ sym = expr->symtree->n.sym;
+ len = strlen (sym->name) + 1;
+
+ for (ref = expr->ref; ref; ref = ref->next)
+ if (ref->type == REF_COMPONENT)
+ len += 2 + strlen (ref->u.c.component->name);
+
+ var_name = XALLOCAVEC (char, len);
+ strcpy (var_name, sym->name);
+
+ for (ref = expr->ref; ref; ref = ref->next)
+ {
+ /* Append component name. */
+ if (ref->type == REF_COMPONENT)
+ {
+ strcat (var_name, "%%");
+ strcat (var_name, ref->u.c.component->name);
+ continue;
+ }
+
+ if (ref->type == REF_ARRAY && ref->u.ar.dimen > 0)
+ {
+ ar = &ref->u.ar;
+ for (dim = 0; dim < ar->dimen; dim++)
+ {
+ if (ar->dimen_type[dim] == DIMEN_ELEMENT)
+ {
+ gfc_se indexse;
+ gfc_init_se (&indexse, NULL);
+ gfc_conv_expr_type (&indexse, ar->start[dim],
+ gfc_array_index_type);
+ trans_array_bound_check (se, ss, indexse.expr, dim,
+ &ar->where,
+ ar->as->type != AS_ASSUMED_SIZE
+ || dim < ar->dimen - 1,
+ var_name);
+ }
+ }
+ }
+ }
+}
+}
+
+
/* Return the offset for an index. Performs bound checking for elemental
dimensions. Single element references are processed separately.
DIM is the array dimension, I is the loop dimension. */
@@ -7823,6 +7889,10 @@ gfc_conv_expr_descriptor (gfc_se *se, gfc_expr *expr)
/* Setup the scalarizing loops and bounds. */
gfc_conv_ss_startstride (&loop);
+ /* Add bounds-checking for elemental dimensions. */
+ if ((gfc_option.rtcheck & GFC_RTCHECK_BOUNDS) && !expr->no_bounds_check)
+array_bound_check_elemental (se, ss, expr);
+
if (need_tmp)
{
if (expr->ts.type == BT_CHARACTER
diff --git a/gcc/testsuite/gfortran.dg/bounds_check_fail_6.f90 b/gcc/testsuite/gfortran.dg/bounds_check_fail_6.f90
new file mode 100644
index 000..90329131158
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/bounds_check_fail_6.f90
@@ -0,0 +1,29 @@
+! { dg-do run }
+! { dg-additional-options "-fcheck=bounds -g -fdump-tree-original" }
+! { dg-output "At line 18 .*" }
+! { dg-shouldfail "dimension 3 of array 'u%z' outside of expected range" }
+!
+! PR fortran/30802 - improve bounds-checking for array sections
+
+program test
+ implicit none
+ integer :: k = 0
+ int
