> On Aug 1, 2022, at 3:13 AM, Richard Biener <rguent...@suse.de> wrote:
>
> On Fri, 29 Jul 2022, Qing Zhao wrote:
>
>>
>>
>>> On Jul 28, 2022, at 3:28 AM, Richard Biener <rguent...@suse.de> wrote:
>>>
>>> On Tue, 19 Jul 2022, Qing Zhao wrote:
>>>
>>>> From a09f39ded462611286a44d9e8273de8342673ba2 Mon Sep 17 00:00:00 2001
>>>> From: Qing Zhao <qing.z...@oracle.com>
>>>> Date: Mon, 18 Jul 2022 18:12:26 +0000
>>>> Subject: [PATCH 2/2] Use new flag DECL_NOT_FLEXARRAY in
>>>> __builtin_object_size
>>>> [PR101836]
>>>>
>>>> Use new flag DECL_NOT_FLEXARRAY to determine whether the trailing array
>>>> of a structure is flexible array member in __builtin_object_size.
>>>>
>>>> gcc/ChangeLog:
>>>>
>>>> PR tree-optimization/101836
>>>> * tree-object-size.cc (addr_object_size): Use array_at_struct_end_p
>>>> and DECL_NOT_FLEXARRAY to determine a flexible array member reference.
>>>>
>>>> gcc/testsuite/ChangeLog:
>>>>
>>>> PR tree-optimization/101836
>>>> * gcc.dg/pr101836.c: New test.
>>>> * gcc.dg/pr101836_1.c: New test.
>>>> * gcc.dg/pr101836_2.c: New test.
>>>> * gcc.dg/pr101836_3.c: New test.
>>>> * gcc.dg/pr101836_4.c: New test.
>>>> * gcc.dg/pr101836_5.c: New test.
>>>> * gcc.dg/strict-flex-array-2.c: New test.
>>>> * gcc.dg/strict-flex-array-3.c: New test.
>>>> ---
>>>> gcc/testsuite/gcc.dg/pr101836.c | 60 ++++++++++++++++++++++
>>>> gcc/testsuite/gcc.dg/pr101836_1.c | 60 ++++++++++++++++++++++
>>>> gcc/testsuite/gcc.dg/pr101836_2.c | 60 ++++++++++++++++++++++
>>>> gcc/testsuite/gcc.dg/pr101836_3.c | 60 ++++++++++++++++++++++
>>>> gcc/testsuite/gcc.dg/pr101836_4.c | 60 ++++++++++++++++++++++
>>>> gcc/testsuite/gcc.dg/pr101836_5.c | 60 ++++++++++++++++++++++
>>>> gcc/testsuite/gcc.dg/strict-flex-array-2.c | 60 ++++++++++++++++++++++
>>>> gcc/testsuite/gcc.dg/strict-flex-array-3.c | 60 ++++++++++++++++++++++
>>>> gcc/tree-object-size.cc | 18 +++----
>>>> 9 files changed, 489 insertions(+), 9 deletions(-)
>>>> create mode 100644 gcc/testsuite/gcc.dg/pr101836.c
>>>> create mode 100644 gcc/testsuite/gcc.dg/pr101836_1.c
>>>> create mode 100644 gcc/testsuite/gcc.dg/pr101836_2.c
>>>> create mode 100644 gcc/testsuite/gcc.dg/pr101836_3.c
>>>> create mode 100644 gcc/testsuite/gcc.dg/pr101836_4.c
>>>> create mode 100644 gcc/testsuite/gcc.dg/pr101836_5.c
>>>> create mode 100644 gcc/testsuite/gcc.dg/strict-flex-array-2.c
>>>> create mode 100644 gcc/testsuite/gcc.dg/strict-flex-array-3.c
>>>>
>>>> diff --git a/gcc/testsuite/gcc.dg/pr101836.c
>>>> b/gcc/testsuite/gcc.dg/pr101836.c
>>>> new file mode 100644
>>>> index 00000000000..e5b4e5160a4
>>>> --- /dev/null
>>>> +++ b/gcc/testsuite/gcc.dg/pr101836.c
>>>> @@ -0,0 +1,60 @@
>>>> +/* -fstrict-flex-array is aliased with -ftrict-flex-array=3, which is the
>>>> + strictest, only [] is treated as flexible array. */
>>>> +/* PR tree-optimization/101836 */
>>>> +/* { dg-do run } */
>>>> +/* { dg-options "-O2 -fstrict-flex-array" } */
>>>> +
>>>> +#include <stdio.h>
>>>> +
>>>> +#define expect(p, _v) do { \
>>>> + size_t v = _v; \
>>>> + if (p == v) \
>>>> + printf("ok: %s == %zd\n", #p, p); \
>>>> + else \
>>>> + { \
>>>> + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \
>>>> + __builtin_abort (); \
>>>> + } \
>>>> +} while (0);
>>>> +
>>>> +struct trailing_array_1 {
>>>> + int a;
>>>> + int b;
>>>> + int c[4];
>>>> +};
>>>> +
>>>> +struct trailing_array_2 {
>>>> + int a;
>>>> + int b;
>>>> + int c[1];
>>>> +};
>>>> +
>>>> +struct trailing_array_3 {
>>>> + int a;
>>>> + int b;
>>>> + int c[0];
>>>> +};
>>>> +struct trailing_array_4 {
>>>> + int a;
>>>> + int b;
>>>> + int c[];
>>>> +};
>>>> +
>>>> +void __attribute__((__noinline__)) stuff(
>>>> + struct trailing_array_1 *normal,
>>>> + struct trailing_array_2 *trailing_1,
>>>> + struct trailing_array_3 *trailing_0,
>>>> + struct trailing_array_4 *trailing_flex)
>>>> +{
>>>> + expect(__builtin_object_size(normal->c, 1), 16);
>>>> + expect(__builtin_object_size(trailing_1->c, 1), 4);
>>>> + expect(__builtin_object_size(trailing_0->c, 1), 0);
>>>> + expect(__builtin_object_size(trailing_flex->c, 1), -1);
>>>> +}
>>>> +
>>>> +int main(int argc, char *argv[])
>>>> +{
>>>> + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void
>>>> *)argv[0]);
>>>> +
>>>> + return 0;
>>>> +}
>>>> diff --git a/gcc/testsuite/gcc.dg/pr101836_1.c
>>>> b/gcc/testsuite/gcc.dg/pr101836_1.c
>>>> new file mode 100644
>>>> index 00000000000..30ea20427a5
>>>> --- /dev/null
>>>> +++ b/gcc/testsuite/gcc.dg/pr101836_1.c
>>>> @@ -0,0 +1,60 @@
>>>> +/* -fstrict-flex-array=3 is the strictest, only [] is treated as
>>>> + flexible array. */
>>>> +/* PR tree-optimization/101836 */
>>>> +/* { dg-do run } */
>>>> +/* { dg-options "-O2 -fstrict-flex-array=3" } */
>>>> +
>>>> +#include <stdio.h>
>>>> +
>>>> +#define expect(p, _v) do { \
>>>> + size_t v = _v; \
>>>> + if (p == v) \
>>>> + printf("ok: %s == %zd\n", #p, p); \
>>>> + else \
>>>> + { \
>>>> + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \
>>>> + __builtin_abort (); \
>>>> + } \
>>>> +} while (0);
>>>> +
>>>> +struct trailing_array_1 {
>>>> + int a;
>>>> + int b;
>>>> + int c[4];
>>>> +};
>>>> +
>>>> +struct trailing_array_2 {
>>>> + int a;
>>>> + int b;
>>>> + int c[1];
>>>> +};
>>>> +
>>>> +struct trailing_array_3 {
>>>> + int a;
>>>> + int b;
>>>> + int c[0];
>>>> +};
>>>> +struct trailing_array_4 {
>>>> + int a;
>>>> + int b;
>>>> + int c[];
>>>> +};
>>>> +
>>>> +void __attribute__((__noinline__)) stuff(
>>>> + struct trailing_array_1 *normal,
>>>> + struct trailing_array_2 *trailing_1,
>>>> + struct trailing_array_3 *trailing_0,
>>>> + struct trailing_array_4 *trailing_flex)
>>>> +{
>>>> + expect(__builtin_object_size(normal->c, 1), 16);
>>>> + expect(__builtin_object_size(trailing_1->c, 1), 4);
>>>> + expect(__builtin_object_size(trailing_0->c, 1), 0);
>>>> + expect(__builtin_object_size(trailing_flex->c, 1), -1);
>>>> +}
>>>> +
>>>> +int main(int argc, char *argv[])
>>>> +{
>>>> + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void
>>>> *)argv[0]);
>>>> +
>>>> + return 0;
>>>> +}
>>>> diff --git a/gcc/testsuite/gcc.dg/pr101836_2.c
>>>> b/gcc/testsuite/gcc.dg/pr101836_2.c
>>>> new file mode 100644
>>>> index 00000000000..ebbe88f433c
>>>> --- /dev/null
>>>> +++ b/gcc/testsuite/gcc.dg/pr101836_2.c
>>>> @@ -0,0 +1,60 @@
>>>> +/* When -fstrict-flex-array=2, only [] and [0] are treated as flexiable
>>>> + arrays. */
>>>> +/* PR tree-optimization/101836 */
>>>> +/* { dg-do run } */
>>>> +/* { dg-options "-O2 -fstrict-flex-array=2" } */
>>>> +
>>>> +#include <stdio.h>
>>>> +
>>>> +#define expect(p, _v) do { \
>>>> + size_t v = _v; \
>>>> + if (p == v) \
>>>> + printf("ok: %s == %zd\n", #p, p); \
>>>> + else \
>>>> + { \
>>>> + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \
>>>> + __builtin_abort (); \
>>>> + } \
>>>> +} while (0);
>>>> +
>>>> +struct trailing_array_1 {
>>>> + int a;
>>>> + int b;
>>>> + int c[4];
>>>> +};
>>>> +
>>>> +struct trailing_array_2 {
>>>> + int a;
>>>> + int b;
>>>> + int c[1];
>>>> +};
>>>> +
>>>> +struct trailing_array_3 {
>>>> + int a;
>>>> + int b;
>>>> + int c[0];
>>>> +};
>>>> +struct trailing_array_4 {
>>>> + int a;
>>>> + int b;
>>>> + int c[];
>>>> +};
>>>> +
>>>> +void __attribute__((__noinline__)) stuff(
>>>> + struct trailing_array_1 *normal,
>>>> + struct trailing_array_2 *trailing_1,
>>>> + struct trailing_array_3 *trailing_0,
>>>> + struct trailing_array_4 *trailing_flex)
>>>> +{
>>>> + expect(__builtin_object_size(normal->c, 1), 16);
>>>> + expect(__builtin_object_size(trailing_1->c, 1), 4);
>>>> + expect(__builtin_object_size(trailing_0->c, 1), -1);
>>>> + expect(__builtin_object_size(trailing_flex->c, 1), -1);
>>>> +}
>>>> +
>>>> +int main(int argc, char *argv[])
>>>> +{
>>>> + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void
>>>> *)argv[0]);
>>>> +
>>>> + return 0;
>>>> +}
>>>> diff --git a/gcc/testsuite/gcc.dg/pr101836_3.c
>>>> b/gcc/testsuite/gcc.dg/pr101836_3.c
>>>> new file mode 100644
>>>> index 00000000000..d4ba0afe5bc
>>>> --- /dev/null
>>>> +++ b/gcc/testsuite/gcc.dg/pr101836_3.c
>>>> @@ -0,0 +1,60 @@
>>>> +/* When -fstrict-flex-array=1, [], [0], and [1] are treated as flexible
>>>> + arrays. */
>>>> +/* PR tree-optimization/101836 */
>>>> +/* { dg-do run } */
>>>> +/* { dg-options "-O2 -fstrict-flex-array=1" } */
>>>> +
>>>> +#include <stdio.h>
>>>> +
>>>> +#define expect(p, _v) do { \
>>>> + size_t v = _v; \
>>>> + if (p == v) \
>>>> + printf("ok: %s == %zd\n", #p, p); \
>>>> + else \
>>>> + { \
>>>> + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \
>>>> + __builtin_abort (); \
>>>> + } \
>>>> +} while (0);
>>>> +
>>>> +struct trailing_array_1 {
>>>> + int a;
>>>> + int b;
>>>> + int c[4];
>>>> +};
>>>> +
>>>> +struct trailing_array_2 {
>>>> + int a;
>>>> + int b;
>>>> + int c[1];
>>>> +};
>>>> +
>>>> +struct trailing_array_3 {
>>>> + int a;
>>>> + int b;
>>>> + int c[0];
>>>> +};
>>>> +struct trailing_array_4 {
>>>> + int a;
>>>> + int b;
>>>> + int c[];
>>>> +};
>>>> +
>>>> +void __attribute__((__noinline__)) stuff(
>>>> + struct trailing_array_1 *normal,
>>>> + struct trailing_array_2 *trailing_1,
>>>> + struct trailing_array_3 *trailing_0,
>>>> + struct trailing_array_4 *trailing_flex)
>>>> +{
>>>> + expect(__builtin_object_size(normal->c, 1), 16);
>>>> + expect(__builtin_object_size(trailing_1->c, 1), -1);
>>>> + expect(__builtin_object_size(trailing_0->c, 1), -1);
>>>> + expect(__builtin_object_size(trailing_flex->c, 1), -1);
>>>> +}
>>>> +
>>>> +int main(int argc, char *argv[])
>>>> +{
>>>> + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void
>>>> *)argv[0]);
>>>> +
>>>> + return 0;
>>>> +}
>>>> diff --git a/gcc/testsuite/gcc.dg/pr101836_4.c
>>>> b/gcc/testsuite/gcc.dg/pr101836_4.c
>>>> new file mode 100644
>>>> index 00000000000..b10d3ce312d
>>>> --- /dev/null
>>>> +++ b/gcc/testsuite/gcc.dg/pr101836_4.c
>>>> @@ -0,0 +1,60 @@
>>>> +/* when -fstrict-flex-array=0, all trailing arrays are treated as
>>>> + flexible arrays. */
>>>> +/* PR tree-optimization/101836 */
>>>> +/* { dg-do run } */
>>>> +/* { dg-options "-O2 -fstrict-flex-array=0" } */
>>>> +
>>>> +#include <stdio.h>
>>>> +
>>>> +#define expect(p, _v) do { \
>>>> + size_t v = _v; \
>>>> + if (p == v) \
>>>> + printf("ok: %s == %zd\n", #p, p); \
>>>> + else \
>>>> + { \
>>>> + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \
>>>> + __builtin_abort (); \
>>>> + } \
>>>> +} while (0);
>>>> +
>>>> +struct trailing_array_1 {
>>>> + int a;
>>>> + int b;
>>>> + int c[4];
>>>> +};
>>>> +
>>>> +struct trailing_array_2 {
>>>> + int a;
>>>> + int b;
>>>> + int c[1];
>>>> +};
>>>> +
>>>> +struct trailing_array_3 {
>>>> + int a;
>>>> + int b;
>>>> + int c[0];
>>>> +};
>>>> +struct trailing_array_4 {
>>>> + int a;
>>>> + int b;
>>>> + int c[];
>>>> +};
>>>> +
>>>> +void __attribute__((__noinline__)) stuff(
>>>> + struct trailing_array_1 *normal,
>>>> + struct trailing_array_2 *trailing_1,
>>>> + struct trailing_array_3 *trailing_0,
>>>> + struct trailing_array_4 *trailing_flex)
>>>> +{
>>>> + expect(__builtin_object_size(normal->c, 1), -1);
>>>> + expect(__builtin_object_size(trailing_1->c, 1), -1);
>>>> + expect(__builtin_object_size(trailing_0->c, 1), -1);
>>>> + expect(__builtin_object_size(trailing_flex->c, 1), -1);
>>>> +}
>>>> +
>>>> +int main(int argc, char *argv[])
>>>> +{
>>>> + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void
>>>> *)argv[0]);
>>>> +
>>>> + return 0;
>>>> +}
>>>> diff --git a/gcc/testsuite/gcc.dg/pr101836_5.c
>>>> b/gcc/testsuite/gcc.dg/pr101836_5.c
>>>> new file mode 100644
>>>> index 00000000000..2f6b5f7ae1f
>>>> --- /dev/null
>>>> +++ b/gcc/testsuite/gcc.dg/pr101836_5.c
>>>> @@ -0,0 +1,60 @@
>>>> +/* -fno-strict-flex-array is aliased to -fstrict-flex-array=0,
>>>> + all trailing arrays are treated as flexible array. */
>>>> +/* PR tree-optimization/101836 */
>>>> +/* { dg-do run } */
>>>> +/* { dg-options "-O2 -fno-strict-flex-array" } */
>>>> +
>>>> +#include <stdio.h>
>>>> +
>>>> +#define expect(p, _v) do { \
>>>> + size_t v = _v; \
>>>> + if (p == v) \
>>>> + printf("ok: %s == %zd\n", #p, p); \
>>>> + else \
>>>> + { \
>>>> + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \
>>>> + __builtin_abort (); \
>>>> + } \
>>>> +} while (0);
>>>> +
>>>> +struct trailing_array_1 {
>>>> + int a;
>>>> + int b;
>>>> + int c[4];
>>>> +};
>>>> +
>>>> +struct trailing_array_2 {
>>>> + int a;
>>>> + int b;
>>>> + int c[1];
>>>> +};
>>>> +
>>>> +struct trailing_array_3 {
>>>> + int a;
>>>> + int b;
>>>> + int c[0];
>>>> +};
>>>> +struct trailing_array_4 {
>>>> + int a;
>>>> + int b;
>>>> + int c[];
>>>> +};
>>>> +
>>>> +void __attribute__((__noinline__)) stuff(
>>>> + struct trailing_array_1 *normal,
>>>> + struct trailing_array_2 *trailing_1,
>>>> + struct trailing_array_3 *trailing_0,
>>>> + struct trailing_array_4 *trailing_flex)
>>>> +{
>>>> + expect(__builtin_object_size(normal->c, 1), -1);
>>>> + expect(__builtin_object_size(trailing_1->c, 1), -1);
>>>> + expect(__builtin_object_size(trailing_0->c, 1), -1);
>>>> + expect(__builtin_object_size(trailing_flex->c, 1), -1);
>>>> +}
>>>> +
>>>> +int main(int argc, char *argv[])
>>>> +{
>>>> + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void
>>>> *)argv[0]);
>>>> +
>>>> + return 0;
>>>> +}
>>>> diff --git a/gcc/testsuite/gcc.dg/strict-flex-array-2.c
>>>> b/gcc/testsuite/gcc.dg/strict-flex-array-2.c
>>>> new file mode 100644
>>>> index 00000000000..326ddcfeda5
>>>> --- /dev/null
>>>> +++ b/gcc/testsuite/gcc.dg/strict-flex-array-2.c
>>>> @@ -0,0 +1,60 @@
>>>> +/* test the combination of attribute strict_flex_array and option
>>>> + -fstrict-flex-array: when both attribute and option specified,
>>>> + attribute will have higher priority. */
>>>> +/* { dg-do run } */
>>>> +/* { dg-options "-O2 -fstrict-flex-array=3" } */
>>>> +
>>>> +#include <stdio.h>
>>>> +
>>>> +#define expect(p, _v) do { \
>>>> + size_t v = _v; \
>>>> + if (p == v) \
>>>> + printf("ok: %s == %zd\n", #p, p); \
>>>> + else \
>>>> + { \
>>>> + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \
>>>> + __builtin_abort (); \
>>>> + } \
>>>> +} while (0);
>>>> +
>>>> +struct trailing_array_1 {
>>>> + int a;
>>>> + int b;
>>>> + int c[4] __attribute__ ((strict_flex_array (0)));
>>>> +};
>>>> +
>>>> +struct trailing_array_2 {
>>>> + int a;
>>>> + int b;
>>>> + int c[1] __attribute__ ((strict_flex_array (1)));
>>>> +};
>>>> +
>>>> +struct trailing_array_3 {
>>>> + int a;
>>>> + int b;
>>>> + int c[0] __attribute__ ((strict_flex_array (2)));
>>>> +};
>>>> +struct trailing_array_4 {
>>>> + int a;
>>>> + int b;
>>>> + int c[];
>>>> +};
>>>> +
>>>> +void __attribute__((__noinline__)) stuff(
>>>> + struct trailing_array_1 *normal,
>>>> + struct trailing_array_2 *trailing_1,
>>>> + struct trailing_array_3 *trailing_0,
>>>> + struct trailing_array_4 *trailing_flex)
>>>> +{
>>>> + expect(__builtin_object_size(normal->c, 1), -1);
>>>> + expect(__builtin_object_size(trailing_1->c, 1), -1);
>>>> + expect(__builtin_object_size(trailing_0->c, 1), -1);
>>>> + expect(__builtin_object_size(trailing_flex->c, 1), -1);
>>>> +}
>>>> +
>>>> +int main(int argc, char *argv[])
>>>> +{
>>>> + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void
>>>> *)argv[0]);
>>>> +
>>>> + return 0;
>>>> +}
>>>> diff --git a/gcc/testsuite/gcc.dg/strict-flex-array-3.c
>>>> b/gcc/testsuite/gcc.dg/strict-flex-array-3.c
>>>> new file mode 100644
>>>> index 00000000000..990c5bb6223
>>>> --- /dev/null
>>>> +++ b/gcc/testsuite/gcc.dg/strict-flex-array-3.c
>>>> @@ -0,0 +1,60 @@
>>>> +/* test the combination of attribute strict_flex_array and option
>>>> + -fstrict-flex-array: when both attribute and option specified,
>>>> + attribute will have higher priority. */
>>>> +/* { dg-do run } */
>>>> +/* { dg-options "-O2 -fstrict-flex-array=0" } */
>>>> +
>>>> +#include <stdio.h>
>>>> +
>>>> +#define expect(p, _v) do { \
>>>> + size_t v = _v; \
>>>> + if (p == v) \
>>>> + printf("ok: %s == %zd\n", #p, p); \
>>>> + else \
>>>> + { \
>>>> + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \
>>>> + __builtin_abort (); \
>>>> + } \
>>>> +} while (0);
>>>> +
>>>> +struct trailing_array_1 {
>>>> + int a;
>>>> + int b;
>>>> + int c[4] __attribute__ ((strict_flex_array (1)));
>>>> +};
>>>> +
>>>> +struct trailing_array_2 {
>>>> + int a;
>>>> + int b;
>>>> + int c[1] __attribute__ ((strict_flex_array (2)));
>>>> +};
>>>> +
>>>> +struct trailing_array_3 {
>>>> + int a;
>>>> + int b;
>>>> + int c[0] __attribute__ ((strict_flex_array (3)));
>>>> +};
>>>> +struct trailing_array_4 {
>>>> + int a;
>>>> + int b;
>>>> + int c[];
>>>> +};
>>>> +
>>>> +void __attribute__((__noinline__)) stuff(
>>>> + struct trailing_array_1 *normal,
>>>> + struct trailing_array_2 *trailing_1,
>>>> + struct trailing_array_3 *trailing_0,
>>>> + struct trailing_array_4 *trailing_flex)
>>>> +{
>>>> + expect(__builtin_object_size(normal->c, 1), 16);
>>>> + expect(__builtin_object_size(trailing_1->c, 1), 4);
>>>> + expect(__builtin_object_size(trailing_0->c, 1), 0);
>>>> + expect(__builtin_object_size(trailing_flex->c, 1), -1);
>>>> +}
>>>> +
>>>> +int main(int argc, char *argv[])
>>>> +{
>>>> + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void
>>>> *)argv[0]);
>>>> +
>>>> + return 0;
>>>> +}
>>>> diff --git a/gcc/tree-object-size.cc b/gcc/tree-object-size.cc
>>>> index 4eb454a4a33..90710ecba72 100644
>>>> --- a/gcc/tree-object-size.cc
>>>> +++ b/gcc/tree-object-size.cc
>>>> @@ -604,9 +604,9 @@ addr_object_size (struct object_size_info *osi,
>>>> const_tree ptr,
>>>> else if (var != pt_var && TREE_CODE (pt_var) == MEM_REF)
>>>> {
>>>> tree v = var;
>>>> - /* For &X->fld, compute object size only if fld isn't the last
>>>> - field, as struct { int i; char c[1]; } is often used instead
>>>> - of flexible array member. */
>>>> + bool is_flexible_array_mem_ref = false;
>>>> + /* For &X->fld, compute object size if fld isn't a flexible array
>>>> + member. */
>>>> while (v && v != pt_var)
>>>> switch (TREE_CODE (v))
>>>> {
>>>> @@ -633,6 +633,9 @@ addr_object_size (struct object_size_info *osi,
>>>> const_tree ptr,
>>>> v = NULL_TREE;
>>>> break;
>>>> }
>>>> + is_flexible_array_mem_ref
>>>> + = array_at_struct_end_p (v)
>>>> + && !DECL_NOT_FLEXARRAY (TREE_OPERAND (v, 1));
>>>
>>> As said in the review for the first patch array_at_struct_end_p should
>>> check DECL_NOT_FLEXARRAY.
>> Okay.
>>
>> Then, should we change the name of “array_at_struct_end_p” to a more
>> descriptive name, for example,”flexible_array_member_p”? Otherwise, It’s
>> really confusing.
>
> It has been that way since forever, so please don't (at least not as
> part of this series).
Okay, I will keep the name as it in this set of patches.
(However, I do think that we should change the name of this routine, it’s
really confusing…)
Qing
>
>>
>>
>>>
>>> OK with removing the extra check here.
>>
>> Okay.
>>
>>
>> thanks.
>>
>> Qing
>>>
>>>> while (v != pt_var && TREE_CODE (v) == COMPONENT_REF)
>>>> if (TREE_CODE (TREE_TYPE (TREE_OPERAND (v, 0)))
>>>> != UNION_TYPE
>>>> @@ -645,12 +648,9 @@ addr_object_size (struct object_size_info *osi,
>>>> const_tree ptr,
>>>> && TREE_CODE (TREE_TYPE (TREE_OPERAND (v, 0)))
>>>> == RECORD_TYPE)
>>>> {
>>>> - tree fld_chain = DECL_CHAIN (TREE_OPERAND (v, 1));
>>>> - for (; fld_chain; fld_chain = DECL_CHAIN (fld_chain))
>>>> - if (TREE_CODE (fld_chain) == FIELD_DECL)
>>>> - break;
>>>> -
>>>> - if (fld_chain)
>>>> + /* compute object size only if v is not a
>>>> + flexible array member. */
>>>> + if (!is_flexible_array_mem_ref)
>>>> {
>>>> v = NULL_TREE;
>>>> break;
>>>>
>>>
>>> --
>>> Richard Biener <rguent...@suse.de>
>>> SUSE Software Solutions Germany GmbH, Frankenstrasse 146, 90461 Nuernberg,
>>> Germany; GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman;
>>> HRB 36809 (AG Nuernberg)
>>
>>
>
> --
> Richard Biener <rguent...@suse.de>
> SUSE Software Solutions Germany GmbH, Frankenstrasse 146, 90461 Nuernberg,
> Germany; GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman;
> HRB 36809 (AG Nuernberg)
