* [Bug tree-optimization/82608] missing -Warray-bounds on an out-of-bounds VLA index
[not found] <bug-82608-4@http.gcc.gnu.org/bugzilla/>
@ 2020-06-10 17:53 ` msebor at gcc dot gnu.org
2020-06-10 17:55 ` msebor at gcc dot gnu.org
` (5 subsequent siblings)
6 siblings, 0 replies; 7+ messages in thread
From: msebor at gcc dot gnu.org @ 2020-06-10 17:53 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82608
Martin Sebor <msebor at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Known to fail| |10.1.0, 11.0, 8.4.0, 9.3.0
Last reconfirmed|2019-11-05 00:00:00 |2020-6-10
--- Comment #4 from Martin Sebor <msebor at gcc dot gnu.org> ---
GCC 11 issues -Wuninitialized for all accesses but only because the test case
isn't careful enough to initialize the arrays before using them:
$ gcc -O2 -S -Wall -Wextra pr82608.c
pr82608.c: In function ‘idx_negative’:
pr82608.c:18:11: warning: ‘*(<unknown>)[-99]’ is used uninitialized
[-Wuninitialized]
18 | return a[-99]; // -Warray-bounds (since GCC 8)
| ~^~~~~
pr82608.c: In function ‘idx_cst_too_big’:
pr82608.c:25:11: warning: ‘*(<unknown>)[<unknown>]’ is used uninitialized
[-Wuninitialized]
25 | return a[n + 1]; // missing _Warray-bounds
| ~^~~~~~~
pr82608.c: In function ‘idx_out_of_type_bounds’:
pr82608.c:31:11: warning: ‘*(<unknown>)[2147483647]’ is used uninitialized
[-Wuninitialized]
31 | return a[__INT_MAX__]; // missing -Warray-bounds
| ~^~~~~~~~~~~~~
pr82608.c: In function ‘idx_var_too_big’:
pr82608.c:37:11: warning: ‘*(<unknown>)[<unknown>]’ is used uninitialized
[-Wuninitialized]
37 | return a[n + 1]; // missing -Warray-bounds
| ~^~~~~~~
With -Wno-uninitialized or with the arrays initialized GCC still doesn't detect
all the out-of-bounds accesses:
$ cat pr82608.c && gcc -O2 -S -Wall -Wextra pr82608.c
void sink (void*);
int f (unsigned n)
{
if (n < 1 || n > 32)
n = 32;
char vla[n];
sink (vla);
return vla[97]; // missing -Warray-bounds
}
int idx_negative (void)
{
int n = 4;
char a[n];
sink (a);
return a[-99]; // -Warray-bounds (since GCC 8)
}
int idx_cst_too_big (void)
{
int n = 4;
char a[n];
sink (a);
return a[n + 1]; // missing _Warray-bounds
}
int idx_out_of_type_bounds (unsigned char n)
{
char a[n];
sink (a);
return a[__INT_MAX__]; // missing -Warray-bounds
}
int idx_var_too_big (int n)
{
char a[n];
sink (a);
return a[n + 1]; // missing -Warray-bounds
}
pr82608.c: In function ‘idx_negative’:
pr82608.c:17:11: warning: array subscript -99 is below array bounds of
‘char[<U3750> + 1]’ [-Warray-bounds]
17 | return a[-99]; // -Warray-bounds (since GCC 8)
| ~^~~~~
pr82608.c:15:8: note: while referencing ‘a.16’
15 | char a[n];
| ^
pr82608.c: In function ‘idx_cst_too_big’:
pr82608.c:25:11: warning: array subscript 5 is above array bounds of
‘char[<U3ea0> + 1]’ [-Warray-bounds]
25 | return a[n + 1]; // missing _Warray-bounds
| ~^~~~~~~
pr82608.c:23:8: note: while referencing ‘a.18’
23 | char a[n];
| ^
^ permalink raw reply [flat|nested] 7+ messages in thread* [Bug tree-optimization/82608] missing -Warray-bounds on an out-of-bounds VLA index
[not found] <bug-82608-4@http.gcc.gnu.org/bugzilla/>
2020-06-10 17:53 ` [Bug tree-optimization/82608] missing -Warray-bounds on an out-of-bounds VLA index msebor at gcc dot gnu.org
@ 2020-06-10 17:55 ` msebor at gcc dot gnu.org
2020-09-19 23:57 ` cvs-commit at gcc dot gnu.org
` (4 subsequent siblings)
6 siblings, 0 replies; 7+ messages in thread
From: msebor at gcc dot gnu.org @ 2020-06-10 17:55 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82608
Martin Sebor <msebor at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target Milestone|--- |11.0
See Also| |https://gcc.gnu.org/bugzill
| |a/show_bug.cgi?id=50584
Status|NEW |ASSIGNED
--- Comment #5 from Martin Sebor <msebor at gcc dot gnu.org> ---
I'm working a fix for GCC 11 (it handles pr50584 as well).
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[not found] <bug-82608-4@http.gcc.gnu.org/bugzilla/>
2020-06-10 17:53 ` [Bug tree-optimization/82608] missing -Warray-bounds on an out-of-bounds VLA index msebor at gcc dot gnu.org
2020-06-10 17:55 ` msebor at gcc dot gnu.org
@ 2020-09-19 23:57 ` cvs-commit at gcc dot gnu.org
2020-09-20 0:11 ` msebor at gcc dot gnu.org
` (3 subsequent siblings)
6 siblings, 0 replies; 7+ messages in thread
From: cvs-commit at gcc dot gnu.org @ 2020-09-19 23:57 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82608
--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Martin Sebor <msebor@gcc.gnu.org>:
https://gcc.gnu.org/g:3f9a497d1b0dd9da87908a11b59bf364ad40ddca
commit r11-3306-g3f9a497d1b0dd9da87908a11b59bf364ad40ddca
Author: Martin Sebor <msebor@redhat.com>
Date: Sat Sep 19 17:47:29 2020 -0600
Extend -Warray-bounds to detect out-of-bounds accesses to array parameters.
gcc/ChangeLog:
PR middle-end/82608
PR middle-end/94195
PR c/50584
PR middle-end/84051
* gimple-array-bounds.cc (get_base_decl): New function.
(get_ref_size): New function.
(trailing_array): New function.
(array_bounds_checker::check_array_ref): Call them. Handle arrays
declared in function parameters.
(array_bounds_checker::check_mem_ref): Same. Handle references to
dynamically allocated arrays.
gcc/testsuite/ChangeLog:
PR middle-end/82608
PR middle-end/94195
PR c/50584
PR middle-end/84051
* c-c++-common/Warray-bounds.c: Adjust.
* gcc.dg/Wbuiltin-declaration-mismatch-9.c: Adjust.
* gcc.dg/Warray-bounds-63.c: New test.
* gcc.dg/Warray-bounds-64.c: New test.
* gcc.dg/Warray-bounds-65.c: New test.
* gcc.dg/Warray-bounds-66.c: New test.
* gcc.dg/Warray-bounds-67.c: New test.
^ permalink raw reply [flat|nested] 7+ messages in thread* [Bug tree-optimization/82608] missing -Warray-bounds on an out-of-bounds VLA index
[not found] <bug-82608-4@http.gcc.gnu.org/bugzilla/>
` (2 preceding siblings ...)
2020-09-19 23:57 ` cvs-commit at gcc dot gnu.org
@ 2020-09-20 0:11 ` msebor at gcc dot gnu.org
2021-04-27 11:38 ` jakub at gcc dot gnu.org
` (2 subsequent siblings)
6 siblings, 0 replies; 7+ messages in thread
From: msebor at gcc dot gnu.org @ 2020-09-20 0:11 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82608
--- Comment #7 from Martin Sebor <msebor at gcc dot gnu.org> ---
Despite the enhancement the test case in comment #0 is still not diagnosed (the
n argument has no range).
^ permalink raw reply [flat|nested] 7+ messages in thread* [Bug tree-optimization/82608] missing -Warray-bounds on an out-of-bounds VLA index
[not found] <bug-82608-4@http.gcc.gnu.org/bugzilla/>
` (3 preceding siblings ...)
2020-09-20 0:11 ` msebor at gcc dot gnu.org
@ 2021-04-27 11:38 ` jakub at gcc dot gnu.org
2021-07-28 7:04 ` rguenth at gcc dot gnu.org
2022-03-17 20:15 ` msebor at gcc dot gnu.org
6 siblings, 0 replies; 7+ messages in thread
From: jakub at gcc dot gnu.org @ 2021-04-27 11:38 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82608
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target Milestone|11.0 |11.2
--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 11.1 has been released, retargeting bugs to GCC 11.2.
^ permalink raw reply [flat|nested] 7+ messages in thread* [Bug tree-optimization/82608] missing -Warray-bounds on an out-of-bounds VLA index
[not found] <bug-82608-4@http.gcc.gnu.org/bugzilla/>
` (4 preceding siblings ...)
2021-04-27 11:38 ` jakub at gcc dot gnu.org
@ 2021-07-28 7:04 ` rguenth at gcc dot gnu.org
2022-03-17 20:15 ` msebor at gcc dot gnu.org
6 siblings, 0 replies; 7+ messages in thread
From: rguenth at gcc dot gnu.org @ 2021-07-28 7:04 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82608
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target Milestone|11.2 |---
^ permalink raw reply [flat|nested] 7+ messages in thread* [Bug tree-optimization/82608] missing -Warray-bounds on an out-of-bounds VLA index
[not found] <bug-82608-4@http.gcc.gnu.org/bugzilla/>
` (5 preceding siblings ...)
2021-07-28 7:04 ` rguenth at gcc dot gnu.org
@ 2022-03-17 20:15 ` msebor at gcc dot gnu.org
6 siblings, 0 replies; 7+ messages in thread
From: msebor at gcc dot gnu.org @ 2022-03-17 20:15 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82608
Martin Sebor <msebor at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Assignee|msebor at gcc dot gnu.org |unassigned at gcc dot gnu.org
Status|ASSIGNED |NEW
--- Comment #9 from Martin Sebor <msebor at gcc dot gnu.org> ---
I'm no longer working on this.
^ permalink raw reply [flat|nested] 7+ messages in thread