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-rw-r--r--gcc/ChangeLog8
-rw-r--r--gcc/c-common.c54
-rw-r--r--gcc/c-common.h1
-rw-r--r--gcc/c-typeck.c14
-rw-r--r--gcc/cp/ChangeLog5
-rw-r--r--gcc/cp/typeck.c14
-rw-r--r--gcc/doc/invoke.texi9
-rw-r--r--gcc/testsuite/ChangeLog8
-rw-r--r--gcc/testsuite/g++.dg/warn/Warray-bounds-noopt.C123
-rw-r--r--gcc/testsuite/g++.dg/warn/Warray-bounds.C42
-rw-r--r--gcc/testsuite/gcc.dg/Warray-bounds-noopt.c123
-rw-r--r--gcc/testsuite/gcc.dg/Warray-bounds.c42
-rw-r--r--gcc/tree-vrp.c4
13 files changed, 42 insertions, 405 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 221a8fa..f33e88c 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2008-05-02 Simon Baldwin <simonb@google.com>
+
+ PR bootstrap/36108
+ * c-common.h (warn_array_subscript_range): Removed.
+ * c-common.c (warn_array_subscript_range): Ditto.
+ * tree-vrp.c (check_array_ref): Revert to ignoring arrays with size 2.
+ * c-typeck.c (build_array_ref): Remove warn_array_subscript_range.
+
2008-05-02 H.J. Lu <hongjiu.lu@intel.com>
* config/i386/i386.c (ix86_special_builtin_type): New.
diff --git a/gcc/c-common.c b/gcc/c-common.c
index 3fa1649..5858523 100644
--- a/gcc/c-common.c
+++ b/gcc/c-common.c
@@ -7452,60 +7452,6 @@ warn_array_subscript_with_type_char (tree index)
warning (OPT_Wchar_subscripts, "array subscript has type %<char%>");
}
-/* Warn about obvious array bounds errors for fixed size arrays that
- are indexed by a constant. This is a subset of similar checks in
- tree-vrp.c; by doing this here we can get some level of checking
- from non-optimized, non-vrp compilation. Returns true if a warning
- is issued. */
-
-bool
-warn_array_subscript_range (const_tree array, const_tree index)
-{
- if (skip_evaluation == 0
- && TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE
- && TYPE_DOMAIN (TREE_TYPE (array)) && TREE_CODE (index) == INTEGER_CST)
- {
- const_tree max_index;
-
- max_index = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (array)));
- if (max_index && TREE_CODE (max_index) == INTEGER_CST
- && tree_int_cst_lt (max_index, index)
- && !tree_int_cst_equal (index, max_index)
- /* Always allow off-by-one. */
- && !tree_int_cst_equal (int_const_binop (PLUS_EXPR,
- max_index,
- integer_one_node,
- 0),
- index)
- /* Accesses after the end of arrays of size 0 (gcc
- extension) and 1 are likely intentional ("struct
- hack"). Note that max_index is array dimension - 1. */
- && compare_tree_int (max_index, 1) >= 0)
- {
- warning (OPT_Warray_bounds,
- "array subscript is above array bounds");
- return true;
- }
- else
- {
- const_tree min_index;
-
- min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (array)));
- if (min_index && TREE_CODE (min_index) == INTEGER_CST
- && tree_int_cst_lt (index, min_index))
- {
- warning (OPT_Warray_bounds,
- compare_tree_int (min_index, 0) == 0
- ? "array subscript is negative"
- : "array subscript is below array bounds");
- return true;
- }
- }
- }
-
- return false;
-}
-
/* Implement -Wparentheses for the unexpected C precedence rules, to
cover cases like x + y << z which readers are likely to
misinterpret. We have seen an expression in which CODE is a binary
diff --git a/gcc/c-common.h b/gcc/c-common.h
index 4f4a414..c403bee 100644
--- a/gcc/c-common.h
+++ b/gcc/c-common.h
@@ -893,7 +893,6 @@ extern int complete_array_type (tree *, tree, bool);
extern tree builtin_type_for_size (int, bool);
extern void warn_array_subscript_with_type_char (tree);
-extern bool warn_array_subscript_range (const_tree, const_tree);
extern void warn_about_parentheses (enum tree_code, enum tree_code,
enum tree_code);
extern void warn_for_unused_label (tree label);
diff --git a/gcc/c-typeck.c b/gcc/c-typeck.c
index dc4cb2b..2f84282 100644
--- a/gcc/c-typeck.c
+++ b/gcc/c-typeck.c
@@ -2086,12 +2086,7 @@ build_array_ref (tree array, tree index)
if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
{
- tree rval, type, ref;
- bool has_warned_on_bounds_check = false;
-
- /* Warn about any obvious array bounds errors for fixed size arrays that
- are indexed by a constant. */
- has_warned_on_bounds_check = warn_array_subscript_range (array, index);
+ tree rval, type;
/* An array that is indexed by a non-constant
cannot be stored in a register; we must be able to do
@@ -2144,12 +2139,7 @@ build_array_ref (tree array, tree index)
in an inline function.
Hope it doesn't break something else. */
| TREE_THIS_VOLATILE (array));
- ref = require_complete_type (fold (rval));
-
- /* Suppress bounds warning in tree-vrp.c if already warned here. */
- if (has_warned_on_bounds_check)
- TREE_NO_WARNING (ref) = 1;
- return ref;
+ return require_complete_type (fold (rval));
}
else
{
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 29b70d0..5bbeda6 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,8 @@
+2008-05-02 Simon Baldwin <simonb@google.com>
+
+ PR bootstrap/36108
+ * typeck.c (build_array_ref): Remove warn_array_subscript_range.
+
2008-05-01 Simon Baldwin <simonb@google.com>
* typeck.c (build_array_ref): Call warn_array_subscript_range.
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index 1447182..bf264ad 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -2556,8 +2556,7 @@ build_array_ref (tree array, tree idx)
if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
{
- bool has_warned_on_bounds_check = false;
- tree rval, type, ref;
+ tree rval, type;
warn_array_subscript_with_type_char (idx);
@@ -2574,10 +2573,6 @@ build_array_ref (tree array, tree idx)
pointer arithmetic.) */
idx = perform_integral_promotions (idx);
- /* Warn about any obvious array bounds errors for fixed size arrays that
- are indexed by a constant. */
- has_warned_on_bounds_check = warn_array_subscript_range (array, idx);
-
/* An array that is indexed by a non-constant
cannot be stored in a register; we must be able to do
address arithmetic on its address.
@@ -2628,12 +2623,7 @@ build_array_ref (tree array, tree idx)
|= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
TREE_THIS_VOLATILE (rval)
|= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
- ref = require_complete_type (fold_if_not_in_template (rval));
-
- /* Suppress bounds warning in tree-vrp.c if already warned here. */
- if (has_warned_on_bounds_check)
- TREE_NO_WARNING (ref) = 1;
- return ref;
+ return require_complete_type (fold_if_not_in_template (rval));
}
{
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index c147219..dfd22af 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -2679,7 +2679,7 @@ Options} and @ref{Objective-C and Objective-C++ Dialect Options}.
@option{-Wall} turns on the following warning flags:
@gccoptlist{-Waddress @gol
--Warray-bounds @r{(some checks, but more complete with} @option{-O2}@r{)} @gol
+-Warray-bounds @r{(only with} @option{-O2}@r{)} @gol
-Wc++0x-compat @gol
-Wchar-subscripts @gol
-Wimplicit-int @gol
@@ -3382,10 +3382,9 @@ false positives.
@item -Warray-bounds
@opindex Wno-array-bounds
@opindex Warray-bounds
-This option detects some cases of out-of-bounds accesses in unoptimized
-compilations. More cases are detected when @option{-ftree-vrp} is enabled.
-(The @option{-ftree-vrp} option is enabled automatically when compiling with
-@option{-O2} or higher optimization options.)
+This option is only active when @option{-ftree-vrp} is active
+(default for -O2 and above). It warns about subscripts to arrays
+that are always out of bounds. This warning is enabled by @option{-Wall}.
@item -Wno-div-by-zero
@opindex Wno-div-by-zero
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 82d3a4d..949a3de 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2008-05-01 Simon Baldwin <simonb@google.com>
+
+ PR bootstrap/36108
+ * testsuite/gcc.dg/Warray-bounds.c: Removed frontend warnings update.
+ * testsuite/g++.dg/warn/Warray-bounds.c: Ditto.
+ * testsuite/gcc.dg/Warray-bounds-noopt.c: Removed testcase.
+ * testsuite/g++.dg/warn/Warray-bounds-noopt.c: Ditto.
+
2008-05-01 Bud Davis <bdavis9659@sbcglobal.net>
PR fortran/PR35940
diff --git a/gcc/testsuite/g++.dg/warn/Warray-bounds-noopt.C b/gcc/testsuite/g++.dg/warn/Warray-bounds-noopt.C
deleted file mode 100644
index 650f269..0000000
--- a/gcc/testsuite/g++.dg/warn/Warray-bounds-noopt.C
+++ /dev/null
@@ -1,123 +0,0 @@
-/* { dg-do compile } */
-/* { dg-options "-O0 -Warray-bounds" } */
-
-int a[10];
-
-static inline int n(void) {
- __SIZE_TYPE__ strlen(const char *s);
- return strlen("12345");
-}
-
-void g(int *p);
-void h(int p);
-
-int* f(void) {
- int b[10];
- int i;
- struct {
- int c[10];
- } c;
- int p[0], q[1], r[2], s[3], t[4];
-
- a[-1] = 0; /* { dg-warning "array subscript" } */
- a[ 0] = 0;
- a[ 1] = 0;
-
-
- a[ 9] = 0;
- a[10] = 0;
- a[11] = 0; /* { dg-warning "array subscript" } */
- a[2 * n() - 11] = 0;
- a[2 * n() - 10] = 0;
- a[2 * n() - 1] = 0;
- a[2 * n() - 0] = 0;
-
- b[-1] = 0; /* { dg-warning "array subscript" } */
- b[ 0] = 0;
- b[ 1] = 0;
- b[ 9] = 0;
- b[10] = 0;
- b[11] = 0; /* { dg-warning "array subscript" } */
- b[2 * n() - 11] = 0;
- b[2 * n() - 10] = 0;
- b[2 * n() - 1] = 0;
- b[2 * n() - 0] = 0;
-
- c.c[-1] = 0; /* { dg-warning "array subscript" } */
- c.c[ 0] = 0;
- c.c[ 1] = 0;
- c.c[ 9] = 0;
- c.c[10] = 0;
- c.c[11] = 0; /* { dg-warning "array subscript" } */
- c.c[2 * n() - 11] = 0;
- c.c[2 * n() - 10] = 0;
- c.c[2 * n() - 1] = 0;
- c.c[2 * n() - 0] = 0;
-
- g(&a[8]);
- g(&a[9]);
- g(&a[10]);
- g(&a[11]); /* { dg-warning "array subscript" } */
- g(&a[-30]+10); /* { dg-warning "array subscript" } */
- g(&a[-30]+30); /* { dg-warning "array subscript" } */
-
- g(&b[10]);
- g(&c.c[10]);
- g(&b[11]); /* { dg-warning "array subscript" } */
- g(&c.c[11]); /* { dg-warning "array subscript" } */
-
- g(&a[0]);
- g(&b[0]);
- g(&c.c[0]);
-
- g(&a[-1]); /* { dg-warning "array subscript" } */
- g(&b[-1]); /* { dg-warning "array subscript" } */
- h(sizeof a[-1]);
- h(sizeof a[10]);
- h(sizeof b[-1]);
- h(sizeof b[10]);
- h(sizeof c.c[-1]);
- h(sizeof c.c[10]);
-
- p[-1] = 0; /* { dg-warning "array subscript" } */
- p[0] = 0;
- p[1] = 0;
-
- q[-1] = 0; /* { dg-warning "array subscript" } */
- q[0] = 0;
- q[1] = 0;
- q[2] = 0;
-
- r[-1] = 0; /* { dg-warning "array subscript" } */
- r[0] = 0;
- r[1] = 0;
- r[2] = 0;
- r[3] = 0; /* { dg-warning "array subscript" } */
-
- s[-1] = 0; /* { dg-warning "array subscript" } */
- s[0] = 0;
- s[1] = 0;
- s[2] = 0;
- s[3] = 0;
- s[4] = 0; /* { dg-warning "array subscript" } */
-
- t[-1] = 0; /* { dg-warning "array subscript" } */
- t[0] = 0;
- t[1] = 0;
- t[2] = 0;
- t[3] = 0;
- t[4] = 0;
- t[5] = 0; /* { dg-warning "array subscript" } */
-
- if (10 < 10)
- a[10] = 0;
- if (10 < 10)
- b[10] = 0;
- if (-1 >= 0)
- c.c[-1] = 0; /* { dg-warning "array subscript" } */
-
- for (i = 20; i < 30; ++i)
- a[i] = 1;
-
- return a;
-}
diff --git a/gcc/testsuite/g++.dg/warn/Warray-bounds.C b/gcc/testsuite/g++.dg/warn/Warray-bounds.C
index 02fd817..0385516 100644
--- a/gcc/testsuite/g++.dg/warn/Warray-bounds.C
+++ b/gcc/testsuite/g++.dg/warn/Warray-bounds.C
@@ -17,7 +17,6 @@ int* f(void) {
struct {
int c[10];
} c;
- int p[0], q[1], r[2], s[3], t[4];
a[-1] = 0; /* { dg-warning "array subscript" } */
a[ 0] = 0;
@@ -58,11 +57,12 @@ int* f(void) {
g(&a[9]);
g(&a[10]);
g(&a[11]); /* { dg-warning "array subscript" } */
- g(&a[-30]+10); /* { dg-warning "array subscript" } */
- g(&a[-30]+30); /* { dg-warning "array subscript" } */
+ g(&a[-30]+10); /* { dg-warning "array subscript" } */
+ g(&a[-30]+30);
g(&b[10]);
g(&c.c[10]);
+ g(&a[11]); /* { dg-warning "array subscript" } */
g(&b[11]); /* { dg-warning "array subscript" } */
g(&c.c[11]); /* { dg-warning "array subscript" } */
@@ -79,45 +79,13 @@ int* f(void) {
h(sizeof c.c[-1]);
h(sizeof c.c[10]);
- p[-1] = 0; /* { dg-warning "array subscript" } */
- p[0] = 0;
- p[1] = 0;
-
- q[-1] = 0; /* { dg-warning "array subscript" } */
- q[0] = 0;
- q[1] = 0;
- q[2] = 0;
-
- r[-1] = 0; /* { dg-warning "array subscript" } */
- r[0] = 0;
- r[1] = 0;
- r[2] = 0;
- r[3] = 0; /* { dg-warning "array subscript" } */
-
- s[-1] = 0; /* { dg-warning "array subscript" } */
- s[0] = 0;
- s[1] = 0;
- s[2] = 0;
- s[3] = 0;
- s[4] = 0; /* { dg-warning "array subscript" } */
-
- t[-1] = 0; /* { dg-warning "array subscript" } */
- t[0] = 0;
- t[1] = 0;
- t[2] = 0;
- t[3] = 0;
- t[4] = 0;
- t[5] = 0; /* { dg-warning "array subscript" } */
-
if (10 < 10)
a[10] = 0;
if (10 < 10)
b[10] = 0;
if (-1 >= 0)
- c.c[-1] = 0; /* { dg-warning "array subscript" } */
-
- for (i = 20; i < 30; ++i)
- a[i] = 1; /* { dg-warning "array subscript" } */
+ c.c[-1] = 0;
return a;
}
+
diff --git a/gcc/testsuite/gcc.dg/Warray-bounds-noopt.c b/gcc/testsuite/gcc.dg/Warray-bounds-noopt.c
deleted file mode 100644
index 650f269..0000000
--- a/gcc/testsuite/gcc.dg/Warray-bounds-noopt.c
+++ /dev/null
@@ -1,123 +0,0 @@
-/* { dg-do compile } */
-/* { dg-options "-O0 -Warray-bounds" } */
-
-int a[10];
-
-static inline int n(void) {
- __SIZE_TYPE__ strlen(const char *s);
- return strlen("12345");
-}
-
-void g(int *p);
-void h(int p);
-
-int* f(void) {
- int b[10];
- int i;
- struct {
- int c[10];
- } c;
- int p[0], q[1], r[2], s[3], t[4];
-
- a[-1] = 0; /* { dg-warning "array subscript" } */
- a[ 0] = 0;
- a[ 1] = 0;
-
-
- a[ 9] = 0;
- a[10] = 0;
- a[11] = 0; /* { dg-warning "array subscript" } */
- a[2 * n() - 11] = 0;
- a[2 * n() - 10] = 0;
- a[2 * n() - 1] = 0;
- a[2 * n() - 0] = 0;
-
- b[-1] = 0; /* { dg-warning "array subscript" } */
- b[ 0] = 0;
- b[ 1] = 0;
- b[ 9] = 0;
- b[10] = 0;
- b[11] = 0; /* { dg-warning "array subscript" } */
- b[2 * n() - 11] = 0;
- b[2 * n() - 10] = 0;
- b[2 * n() - 1] = 0;
- b[2 * n() - 0] = 0;
-
- c.c[-1] = 0; /* { dg-warning "array subscript" } */
- c.c[ 0] = 0;
- c.c[ 1] = 0;
- c.c[ 9] = 0;
- c.c[10] = 0;
- c.c[11] = 0; /* { dg-warning "array subscript" } */
- c.c[2 * n() - 11] = 0;
- c.c[2 * n() - 10] = 0;
- c.c[2 * n() - 1] = 0;
- c.c[2 * n() - 0] = 0;
-
- g(&a[8]);
- g(&a[9]);
- g(&a[10]);
- g(&a[11]); /* { dg-warning "array subscript" } */
- g(&a[-30]+10); /* { dg-warning "array subscript" } */
- g(&a[-30]+30); /* { dg-warning "array subscript" } */
-
- g(&b[10]);
- g(&c.c[10]);
- g(&b[11]); /* { dg-warning "array subscript" } */
- g(&c.c[11]); /* { dg-warning "array subscript" } */
-
- g(&a[0]);
- g(&b[0]);
- g(&c.c[0]);
-
- g(&a[-1]); /* { dg-warning "array subscript" } */
- g(&b[-1]); /* { dg-warning "array subscript" } */
- h(sizeof a[-1]);
- h(sizeof a[10]);
- h(sizeof b[-1]);
- h(sizeof b[10]);
- h(sizeof c.c[-1]);
- h(sizeof c.c[10]);
-
- p[-1] = 0; /* { dg-warning "array subscript" } */
- p[0] = 0;
- p[1] = 0;
-
- q[-1] = 0; /* { dg-warning "array subscript" } */
- q[0] = 0;
- q[1] = 0;
- q[2] = 0;
-
- r[-1] = 0; /* { dg-warning "array subscript" } */
- r[0] = 0;
- r[1] = 0;
- r[2] = 0;
- r[3] = 0; /* { dg-warning "array subscript" } */
-
- s[-1] = 0; /* { dg-warning "array subscript" } */
- s[0] = 0;
- s[1] = 0;
- s[2] = 0;
- s[3] = 0;
- s[4] = 0; /* { dg-warning "array subscript" } */
-
- t[-1] = 0; /* { dg-warning "array subscript" } */
- t[0] = 0;
- t[1] = 0;
- t[2] = 0;
- t[3] = 0;
- t[4] = 0;
- t[5] = 0; /* { dg-warning "array subscript" } */
-
- if (10 < 10)
- a[10] = 0;
- if (10 < 10)
- b[10] = 0;
- if (-1 >= 0)
- c.c[-1] = 0; /* { dg-warning "array subscript" } */
-
- for (i = 20; i < 30; ++i)
- a[i] = 1;
-
- return a;
-}
diff --git a/gcc/testsuite/gcc.dg/Warray-bounds.c b/gcc/testsuite/gcc.dg/Warray-bounds.c
index 02fd817..bbb5bea 100644
--- a/gcc/testsuite/gcc.dg/Warray-bounds.c
+++ b/gcc/testsuite/gcc.dg/Warray-bounds.c
@@ -17,7 +17,6 @@ int* f(void) {
struct {
int c[10];
} c;
- int p[0], q[1], r[2], s[3], t[4];
a[-1] = 0; /* { dg-warning "array subscript" } */
a[ 0] = 0;
@@ -57,13 +56,13 @@ int* f(void) {
g(&a[8]);
g(&a[9]);
g(&a[10]);
- g(&a[11]); /* { dg-warning "array subscript" } */
- g(&a[-30]+10); /* { dg-warning "array subscript" } */
- g(&a[-30]+30); /* { dg-warning "array subscript" } */
+ g(&a[11]); /* { dg-warning "array subscript" "" { xfail *-*-* } } */
+ g(&a[-30]+10); /* { dg-warning "array subscript" } */
+ g(&a[-30]+30);
g(&b[10]);
g(&c.c[10]);
- g(&b[11]); /* { dg-warning "array subscript" } */
+ g(&b[11]); /* { dg-warning "array subscript" "" { xfail *-*-* } } */
g(&c.c[11]); /* { dg-warning "array subscript" } */
g(&a[0]);
@@ -79,45 +78,16 @@ int* f(void) {
h(sizeof c.c[-1]);
h(sizeof c.c[10]);
- p[-1] = 0; /* { dg-warning "array subscript" } */
- p[0] = 0;
- p[1] = 0;
-
- q[-1] = 0; /* { dg-warning "array subscript" } */
- q[0] = 0;
- q[1] = 0;
- q[2] = 0;
-
- r[-1] = 0; /* { dg-warning "array subscript" } */
- r[0] = 0;
- r[1] = 0;
- r[2] = 0;
- r[3] = 0; /* { dg-warning "array subscript" } */
-
- s[-1] = 0; /* { dg-warning "array subscript" } */
- s[0] = 0;
- s[1] = 0;
- s[2] = 0;
- s[3] = 0;
- s[4] = 0; /* { dg-warning "array subscript" } */
-
- t[-1] = 0; /* { dg-warning "array subscript" } */
- t[0] = 0;
- t[1] = 0;
- t[2] = 0;
- t[3] = 0;
- t[4] = 0;
- t[5] = 0; /* { dg-warning "array subscript" } */
-
if (10 < 10)
a[10] = 0;
if (10 < 10)
b[10] = 0;
if (-1 >= 0)
- c.c[-1] = 0; /* { dg-warning "array subscript" } */
+ c.c[-1] = 0;
for (i = 20; i < 30; ++i)
a[i] = 1; /* { dg-warning "array subscript" } */
return a;
}
+
diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c
index 6103199..4b409e4 100644
--- a/gcc/tree-vrp.c
+++ b/gcc/tree-vrp.c
@@ -4645,8 +4645,8 @@ check_array_ref (tree ref, location_t* locus, bool ignore_off_by_one)
&& TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (ref))) == NULL_TREE)
/* Accesses after the end of arrays of size 0 (gcc
extension) and 1 are likely intentional ("struct
- hack"). Note that up_bound is array dimension - 1. */
- || compare_tree_int (up_bound, 1) < 0)
+ hack"). */
+ || compare_tree_int (up_bound, 1) <= 0)
return;
low_bound = array_ref_low_bound (ref);