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* [Bug middle-end/89428] missing -Wstringop-overflow on a PHI with variable offset
       [not found] <bug-89428-4@http.gcc.gnu.org/bugzilla/>
@ 2020-04-22 21:55 ` msebor at gcc dot gnu.org
  2020-04-26  8:01 ` xerofoify at gmail dot com
                   ` (4 subsequent siblings)
  5 siblings, 0 replies; 6+ messages in thread
From: msebor at gcc dot gnu.org @ 2020-04-22 21:55 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89428

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|                            |10.0, 9.2.0
   Last reconfirmed|                            |2020-04-22
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW

--- Comment #1 from Martin Sebor <msebor at gcc dot gnu.org> ---
No progress in GCC 10.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug middle-end/89428] missing -Wstringop-overflow on a PHI with variable offset
       [not found] <bug-89428-4@http.gcc.gnu.org/bugzilla/>
  2020-04-22 21:55 ` [Bug middle-end/89428] missing -Wstringop-overflow on a PHI with variable offset msebor at gcc dot gnu.org
@ 2020-04-26  8:01 ` xerofoify at gmail dot com
  2020-10-29 19:27 ` msebor at gcc dot gnu.org
                   ` (3 subsequent siblings)
  5 siblings, 0 replies; 6+ messages in thread
From: xerofoify at gmail dot com @ 2020-04-26  8:01 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89428

Nicholas Krause <xerofoify at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |xerofoify at gmail dot com

--- Comment #2 from Nicholas Krause <xerofoify at gmail dot com> ---
Changing i equal to 1 in the second function gives the warning and gets similar
GIMPLE like this to the first function:

<bb 2> [local count: 1073741824]:
  i_3 = MAX_EXPR <i_2(D), 1>;
  _1 = &a + i_3;                                                               
  __builtin_memset (_1, 0, 99); [tail call]                                    
  return;  

Are we assuming somewhere that zero size offsets should for the first argument
of __builtin_memset to be forgotten about? Because I tried it with multiple
numbers other than zero and they all worked to get GIMPLE similar to the above.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug middle-end/89428] missing -Wstringop-overflow on a PHI with variable offset
       [not found] <bug-89428-4@http.gcc.gnu.org/bugzilla/>
  2020-04-22 21:55 ` [Bug middle-end/89428] missing -Wstringop-overflow on a PHI with variable offset msebor at gcc dot gnu.org
  2020-04-26  8:01 ` xerofoify at gmail dot com
@ 2020-10-29 19:27 ` msebor at gcc dot gnu.org
  2020-11-03 15:32 ` msebor at gcc dot gnu.org
                   ` (2 subsequent siblings)
  5 siblings, 0 replies; 6+ messages in thread
From: msebor at gcc dot gnu.org @ 2020-10-29 19:27 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89428

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           See Also|                            |https://gcc.gnu.org/bugzill
                   |                            |a/show_bug.cgi?id=92936

--- Comment #3 from Martin Sebor <msebor at gcc dot gnu.org> ---
See also pr92936.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug middle-end/89428] missing -Wstringop-overflow on a PHI with variable offset
       [not found] <bug-89428-4@http.gcc.gnu.org/bugzilla/>
                   ` (2 preceding siblings ...)
  2020-10-29 19:27 ` msebor at gcc dot gnu.org
@ 2020-11-03 15:32 ` msebor at gcc dot gnu.org
  2020-11-29 22:13 ` cvs-commit at gcc dot gnu.org
  2020-11-29 22:38 ` msebor at gcc dot gnu.org
  5 siblings, 0 replies; 6+ messages in thread
From: msebor at gcc dot gnu.org @ 2020-11-03 15:32 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89428

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |patch
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |msebor at gcc dot gnu.org

--- Comment #4 from Martin Sebor <msebor at gcc dot gnu.org> ---
Fixed in the following patch for pr92936:
https://gcc.gnu.org/pipermail/gcc-patches/2020-November/557807.html

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug middle-end/89428] missing -Wstringop-overflow on a PHI with variable offset
       [not found] <bug-89428-4@http.gcc.gnu.org/bugzilla/>
                   ` (3 preceding siblings ...)
  2020-11-03 15:32 ` msebor at gcc dot gnu.org
@ 2020-11-29 22:13 ` cvs-commit at gcc dot gnu.org
  2020-11-29 22:38 ` msebor at gcc dot gnu.org
  5 siblings, 0 replies; 6+ messages in thread
From: cvs-commit at gcc dot gnu.org @ 2020-11-29 22:13 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89428

--- Comment #5 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:eafe8ee7af13c39805ea09bbf5b4f9ab2a48304a

commit r11-5523-geafe8ee7af13c39805ea09bbf5b4f9ab2a48304a
Author: Martin Sebor <msebor@redhat.com>
Date:   Sun Nov 29 15:09:30 2020 -0700

    Handle PHIs in compute_objsize.

    PR middle-end/92936 - missing warning on a past-the-end store to a PHI
    PR middle-end/92940 - incorrect offset and size in -Wstringop-overflow for
out-of-bounds store into VLA and two offset ranges
    PR middle-end/89428 - missing -Wstringop-overflow on a PHI with variable
offset

    gcc/ChangeLog:

            PR middle-end/92936
            PR middle-end/92940
            PR middle-end/89428
            * builtins.c (access_ref::access_ref): Initialize member.
            (access_ref::phi): New function.
            (access_ref::get_ref): New function.
            (access_ref::add_offset): Remove duplicate assignment.
            (maybe_warn_for_bound): Add "maybe" kind of warning messages.
            (warn_for_access): Same.
            (inform_access): Rename...
            (access_ref::inform_access): ...to this.  Print PHI arguments. 
Format
            offset the same as size and simplify.  Improve printing of
allocation
            functions and VLAs.
            (check_access): Adjust to the above.
            (gimple_parm_array_size): Change argument.
            (handle_min_max_size): New function.
            * builtins.h (class ssa_name_limit_t): Move class here from
            tree-ssa-strlen.c.
            (struct access_ref): Declare new members.
            (gimple_parm_array_size): Change argument.
            * tree-ssa-strlen.c (maybe_warn_overflow): Use access_ref and
simplify.
            (handle_builtin_memcpy): Correct argument passed to
maybe_warn_overflow.
            (handle_builtin_memset): Same.
            (class ssa_name_limit_t): Move class to builtins.{h,c}.

    gcc/testsuite/ChangeLog:

            PR middle-end/92936
            PR middle-end/92940
            PR middle-end/89428
            * c-c++-common/Wstringop-overflow-2.c: Adjust text of expected
            informational notes.
            * g++.dg/warn/Wstringop-overflow-3.C: Same.
            * g++.dg/warn/Wplacement-new-size.C: Remove a test for a no longer
            issued warning.
            * gcc.dg/Warray-bounds-43.c: Removed unused declarations.
            * gcc.dg/Wstringop-overflow-11.c: Remove xfails.
            * gcc.dg/Wstringop-overflow-12.c: Same.
            * gcc.dg/Wstringop-overflow-17.c: Adjust text of expected messages.
            * gcc.dg/Wstringop-overflow-27.c: Same.  Remove xfails.
            * gcc.dg/Wstringop-overflow-28.c: Adjust text of expected messages.
            * gcc.dg/Wstringop-overflow-29.c: Same.
            * gcc.dg/Wstringop-overflow-37.c: Same.
            * gcc.dg/Wstringop-overflow-46.c: Same.
            * gcc.dg/Wstringop-overflow-47.c: Same.
            * gcc.dg/Wstringop-overflow-54.c: Same.
            * gcc.dg/warn-strnlen-no-nul.c: Add expected warning.
            * gcc.dg/Wstringop-overflow-7.c: New test.
            * gcc.dg/Wstringop-overflow-58.c: New test.
            * gcc.dg/Wstringop-overflow-59.c: New test.
            * gcc.dg/Wstringop-overflow-60.c: New test.
            * gcc.dg/Wstringop-overflow-61.c: New test.
            * gcc.dg/Wstringop-overflow-62.c: New test.
            * gcc.dg/Wstringop-overflow-63.c: New test.
            * gcc.dg/Wstringop-overflow-64.c: New test.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug middle-end/89428] missing -Wstringop-overflow on a PHI with variable offset
       [not found] <bug-89428-4@http.gcc.gnu.org/bugzilla/>
                   ` (4 preceding siblings ...)
  2020-11-29 22:13 ` cvs-commit at gcc dot gnu.org
@ 2020-11-29 22:38 ` msebor at gcc dot gnu.org
  5 siblings, 0 replies; 6+ messages in thread
From: msebor at gcc dot gnu.org @ 2020-11-29 22:38 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89428

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED
   Target Milestone|---                         |11.0

--- Comment #6 from Martin Sebor <msebor at gcc dot gnu.org> ---
Resolved by  r11-5523 for GCC 11 which now issues the following warnings for
the test case in comment #0 (the duplicate note needs to be fixed):

$ gcc -O2 -S pr89428.c
pr89428.c: In function ‘f’:
pr89428.c:7:3: warning: ‘__builtin_memset’ writing 7 bytes into a region of
size 6 overflows the destination [-Wstringop-overflow=]
    7 |   __builtin_memset (a + i, 0, 7);   // warning (good)
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
pr89428.c:1:6: note: at offset [1, 2] into destination object ‘a’ of size 7
    1 | char a[7];
      |      ^
pr89428.c: In function ‘g’:
pr89428.c:14:3: warning: ‘__builtin_memset’ writing 99 bytes into a region of
size 7 overflows the destination [-Wstringop-overflow=]
   14 |   __builtin_memset (a + i, 0, 99);   // missing warning (bug)
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
pr89428.c:1:6: note: destination object ‘a’ of size 7
    1 | char a[7];
      |      ^
pr89428.c:1:6: note: destination object ‘a’ of size 7

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2020-11-29 22:38 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2020-04-22 21:55 ` [Bug middle-end/89428] missing -Wstringop-overflow on a PHI with variable offset msebor at gcc dot gnu.org
2020-04-26  8:01 ` xerofoify at gmail dot com
2020-10-29 19:27 ` msebor at gcc dot gnu.org
2020-11-03 15:32 ` msebor at gcc dot gnu.org
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2020-11-29 22:38 ` msebor at gcc dot gnu.org

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