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* [Bug c/81524] Bogus or missing warnings when dereferencing pointer to deallocated stack memory
       [not found] <bug-81524-4@http.gcc.gnu.org/bugzilla/>
@ 2022-02-08 23:01 ` msebor at gcc dot gnu.org
  2022-02-10 21:29 ` fredrik.hederstierna@securitas-direct.com
  2022-02-10 23:35 ` [Bug middle-end/81524] " msebor at gcc dot gnu.org
  2 siblings, 0 replies; 3+ messages in thread
From: msebor at gcc dot gnu.org @ 2022-02-08 23:01 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81524

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |msebor at gcc dot gnu.org
             Status|NEW                         |RESOLVED
   Target Milestone|---                         |12.0
         Resolution|---                         |FIXED
             Blocks|                            |104077

--- Comment #6 from Martin Sebor <msebor at gcc dot gnu.org> ---
As far as I can see this works as requested without sanitization in GCC 12:

$ (set -x; for p in PARAM RETURN BLOCK; do for m in READ WRITE; do gcc
-DTEST_${p}_$m -S -Wall pr81524.c; done; done)
+ for p in PARAM RETURN BLOCK
+ for m in READ WRITE
+ gcc -DTEST_PARAM_READ -S -Wall pr81524.c
pr81524.c: In function ‘test_param_local’:
pr81524.c:33:7: warning: storing the address of local variable ‘local’ in ‘*pp’
[-Wdangling-pointer=]
   33 |   *pp = &local;
      |   ~~~~^~~~~~~~
pr81524.c:32:7: note: ‘local’ declared here
   32 |   int local = 1;
      |       ^~~~~
pr81524.c:32:7: note: ‘pp’ declared here
+ for m in READ WRITE
+ gcc -DTEST_PARAM_WRITE -S -Wall pr81524.c
pr81524.c: In function ‘test_param_local’:
pr81524.c:33:7: warning: storing the address of local variable ‘local’ in ‘*pp’
[-Wdangling-pointer=]
   33 |   *pp = &local;
      |   ~~~~^~~~~~~~
pr81524.c:32:7: note: ‘local’ declared here
   32 |   int local = 1;
      |       ^~~~~
pr81524.c:32:7: note: ‘pp’ declared here
+ for p in PARAM RETURN BLOCK
+ for m in READ WRITE
+ gcc -DTEST_RETURN_READ -S -Wall pr81524.c
pr81524.c: In function ‘test_return_local’:
pr81524.c:42:10: warning: function returns address of local variable
[-Wreturn-local-addr]
   42 |   return &local;
      |          ^~~~~~
+ for m in READ WRITE
+ gcc -DTEST_RETURN_WRITE -S -Wall pr81524.c
pr81524.c: In function ‘test_return_local’:
pr81524.c:42:10: warning: function returns address of local variable
[-Wreturn-local-addr]
   42 |   return &local;
      |          ^~~~~~
+ for p in PARAM RETURN BLOCK
+ for m in READ WRITE
+ gcc -DTEST_BLOCK_READ -S -Wall pr81524.c
pr81524.c: In function ‘main’:
pr81524.c:88:10: warning: using dangling pointer ‘p’ to ‘local’
[-Wdangling-pointer=]
   88 |   return *p;
      |          ^~
pr81524.c:76:9: note: ‘local’ declared here
   76 |     int local = 1;
      |         ^~~~~
pr81524.c:81:3: warning: using dangling pointer ‘p’ to ‘local’
[-Wdangling-pointer=]
   81 |   printf("%d\n", *p);
      |   ^~~~~~~~~~~~~~~~~~
pr81524.c:76:9: note: ‘local’ declared here
   76 |     int local = 1;
      |         ^~~~~
+ for m in READ WRITE
+ gcc -DTEST_BLOCK_WRITE -S -Wall pr81524.c
pr81524.c: In function ‘main’:
pr81524.c:88:10: warning: using dangling pointer ‘p’ to ‘local’
[-Wdangling-pointer=]
   88 |   return *p;
      |          ^~
pr81524.c:76:9: note: ‘local’ declared here
   76 |     int local = 1;
      |         ^~~~~
pr81524.c:84:6: warning: using dangling pointer ‘p’ to ‘local’
[-Wdangling-pointer=]
   84 |   *p = 1;
      |   ~~~^~~
pr81524.c:76:9: note: ‘local’ declared here
   76 |     int local = 1;
      |         ^~~~~


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104077
[Bug 104077] bogus/missing -Wdangling-pointer

^ permalink raw reply	[flat|nested] 3+ messages in thread

* [Bug c/81524] Bogus or missing warnings when dereferencing pointer to deallocated stack memory
       [not found] <bug-81524-4@http.gcc.gnu.org/bugzilla/>
  2022-02-08 23:01 ` [Bug c/81524] Bogus or missing warnings when dereferencing pointer to deallocated stack memory msebor at gcc dot gnu.org
@ 2022-02-10 21:29 ` fredrik.hederstierna@securitas-direct.com
  2022-02-10 23:35 ` [Bug middle-end/81524] " msebor at gcc dot gnu.org
  2 siblings, 0 replies; 3+ messages in thread
From: fredrik.hederstierna@securitas-direct.com @ 2022-02-10 21:29 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81524

--- Comment #7 from Fredrik Hederstierna <fredrik.hederstierna@securitas-direct.com> ---
I tested GCC-12 and it now correctly warns for these test cases.
Great work, thanks!

^ permalink raw reply	[flat|nested] 3+ messages in thread

* [Bug middle-end/81524] Bogus or missing warnings when dereferencing pointer to deallocated stack memory
       [not found] <bug-81524-4@http.gcc.gnu.org/bugzilla/>
  2022-02-08 23:01 ` [Bug c/81524] Bogus or missing warnings when dereferencing pointer to deallocated stack memory msebor at gcc dot gnu.org
  2022-02-10 21:29 ` fredrik.hederstierna@securitas-direct.com
@ 2022-02-10 23:35 ` msebor at gcc dot gnu.org
  2 siblings, 0 replies; 3+ messages in thread
From: msebor at gcc dot gnu.org @ 2022-02-10 23:35 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81524

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|c                           |middle-end

--- Comment #8 from Martin Sebor <msebor at gcc dot gnu.org> ---
Thanks for the confirmation (and for your patience)!

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2022-02-10 23:35 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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     [not found] <bug-81524-4@http.gcc.gnu.org/bugzilla/>
2022-02-08 23:01 ` [Bug c/81524] Bogus or missing warnings when dereferencing pointer to deallocated stack memory msebor at gcc dot gnu.org
2022-02-10 21:29 ` fredrik.hederstierna@securitas-direct.com
2022-02-10 23:35 ` [Bug middle-end/81524] " msebor at gcc dot gnu.org

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