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* [Bug middle-end/105316] New: Seemingly bogus -Wdangling-pointer from ppc/ppc64 kernel printk with gcc12
@ 2022-04-20  3:24 raj.khem at gmail dot com
  2022-04-20  3:29 ` [Bug middle-end/105316] " pinskia at gcc dot gnu.org
  2022-04-20  3:35 ` raj.khem at gmail dot com
  0 siblings, 2 replies; 3+ messages in thread
From: raj.khem at gmail dot com @ 2022-04-20  3:24 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105316

            Bug ID: 105316
           Summary: Seemingly bogus -Wdangling-pointer from ppc/ppc64
                    kernel printk with gcc12
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: raj.khem at gmail dot com
  Target Milestone: ---

I have reduced this case from ppc kernel 5.15, this breaks the kernel build as
the warning is treated as error. 

ftrace.i
======================

int _printk(const char *fmt, ...);

static void ftrace_modify_code() {
 _printk("replaced (%s)", ({ char __str[sizeof("00000000 00000000")]; __str;
}));
}


=====================

powerpc64le-yoe-linux-musl-gcc -c ftrace.i -Werror=dangling-pointer 
ftrace.i: In function 'ftrace_modify_code':
ftrace.i:4:2: error: using a dangling pointer to '__str'
[-Werror=dangling-pointer=]
    4 |  _printk("replaced (%s)", ({ char __str[sizeof("00000000 00000000")];
__str; }));
      | 
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ftrace.i:4:35: note: '__str' declared here
    4 |  _printk("replaced (%s)", ({ char __str[sizeof("00000000 00000000")];
__str; }));
      |                                   ^~~~~
cc1: some warnings being treated as errors

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

* [Bug middle-end/105316] Seemingly bogus -Wdangling-pointer from ppc/ppc64 kernel printk with gcc12
  2022-04-20  3:24 [Bug middle-end/105316] New: Seemingly bogus -Wdangling-pointer from ppc/ppc64 kernel printk with gcc12 raj.khem at gmail dot com
@ 2022-04-20  3:29 ` pinskia at gcc dot gnu.org
  2022-04-20  3:35 ` raj.khem at gmail dot com
  1 sibling, 0 replies; 3+ messages in thread
From: pinskia at gcc dot gnu.org @ 2022-04-20  3:29 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105316

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |INVALID
             Status|UNCONFIRMED                 |RESOLVED

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The warning is correct __str goes out of the scope when the statement
expression ends.

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

* [Bug middle-end/105316] Seemingly bogus -Wdangling-pointer from ppc/ppc64 kernel printk with gcc12
  2022-04-20  3:24 [Bug middle-end/105316] New: Seemingly bogus -Wdangling-pointer from ppc/ppc64 kernel printk with gcc12 raj.khem at gmail dot com
  2022-04-20  3:29 ` [Bug middle-end/105316] " pinskia at gcc dot gnu.org
@ 2022-04-20  3:35 ` raj.khem at gmail dot com
  1 sibling, 0 replies; 3+ messages in thread
From: raj.khem at gmail dot com @ 2022-04-20  3:35 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105316

--- Comment #2 from Khem Raj <raj.khem at gmail dot com> ---
ah yes. Thanks

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

end of thread, other threads:[~2022-04-20  3:35 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-04-20  3:24 [Bug middle-end/105316] New: Seemingly bogus -Wdangling-pointer from ppc/ppc64 kernel printk with gcc12 raj.khem at gmail dot com
2022-04-20  3:29 ` [Bug middle-end/105316] " pinskia at gcc dot gnu.org
2022-04-20  3:35 ` raj.khem at gmail dot com

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