[Bug c/111693] New: Online manual mentions -Wuse-after-free but does not document it further

[Bug c/111693] New: Online manual mentions -Wuse-after-free but does not document it further

[jonathan.leffler at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111693

            Bug ID: 111693
           Summary: Online manual mentions -Wuse-after-free but does not
                    document it further
           Product: gcc
           Version: 13.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jonathan.leffler at gmail dot com
  Target Milestone: ---

In the 13.2.0 documentation
(https://gcc.gnu.org/onlinedocs/gcc-13.2.0/gcc/Warning-Options.html), the list
of options enabled by "-Wall" includes "-Wuse-after-free=2", but there is no
further mention of the option on the page.

Similarly, in the 12.3.0 documentation
(https://gcc.gnu.org/onlinedocs/gcc-12.3.0/gcc/Warning-Options.html), the list
of options enabled by "-Wall" includes "-Wuse-after-free=3", but there is no
further mention of the option on the page.

It is not mentioned at all in earlier manuals, presumably because it wasn't
available in the earlier versions.

It would be helpful to know what the values 2 and 3 mean, and presumably what 1
and 0 mean too.

[Bug c/111693] Online manual mentions -Wuse-after-free but does not document it further

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111693

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Documented here:
https://gcc.gnu.org/onlinedocs/gcc-13.2.0/gcc/C_002b_002b-Dialect-Options.html#index-Wuse-after-free

[Bug c/111693] Online manual mentions -Wuse-after-free but does not document it further

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111693

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

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

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Other warnings are documented on that page too.

[Bug c/111693] Online manual mentions -Wuse-after-free but does not document it further

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111693

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The easiest way to find documentation for an option is to look at the index
located at:
https://gcc.gnu.org/onlinedocs/gcc-13.2.0/gcc/Option-Index.html

And search for the option.

[Bug c/111693] Online manual mentions -Wuse-after-free but does not document it further

[jonathan.leffler at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111693

--- Comment #4 from Jonathan Leffler <jonathan.leffler at gmail dot com> ---
The link
https://gcc.gnu.org/onlinedocs/gcc-13.2.0/gcc/C_002b_002b-Dialect-Options.html#index-Wuse-after-free
is to the "Options Controlling C++ Dialect".

I was using the C compiler, not the C++ compiler, so it is not at all obvious
that I should look at that page — in fact, that page is irrelevant to users of
the C compiler.

The information there should be either copied to the C "Warnings Options" page,
or linked to from the C page, where -Wuse-after-free is only mentioned and not
defined.

Incidentally, under "-Wuse-after-free=1" on the C++ page, there's a typo in:

whether or not the call resulted in an actual reallocatio of memory

The 'n' is missing from 'reallocation'.

[Bug c/111693] Online manual mentions -Wuse-after-free but does not document it further

[jonathan.leffler at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111693

--- Comment #5 from Jonathan Leffler <jonathan.leffler at gmail dot com> ---
The link
https://gcc.gnu.org/onlinedocs/gcc-13.2.0/gcc/C_002b_002b-Dialect-Options.html#index-Wuse-after-free
is to the "Options Controlling C++ Dialect".

I was using the C compiler, not the C++ compiler, so it is not at all obvious
that I should look at that page — in fact, that page is irrelevant to users of
the C compiler.

The information there should be either copied to the C "Warnings Options" page,
or linked to from the C page, where -Wuse-after-free is only mentioned and not
defined.

Incidentally, under "-Wuse-after-free=1" on the C++ page, there's a typo in:

whether or not the call resulted in an actual reallocatio of memory

The 'n' is missing from 'reallocation'.

[Bug c/111693] Online manual mentions -Wuse-after-free but does not document it further

[jonathan.leffler at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111693

Jonathan Leffler <jonathan.leffler at gmail dot com> changed:

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

--- Comment #6 from Jonathan Leffler <jonathan.leffler at gmail dot com> ---
Apologies for the double comment — I got a "mid-air collision" message and
wasn't at all sure how to deal with that.

[Bug c/111693] -Wuse-after-free is documented in the wrong location

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111693

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2023-10-04
            Summary|Online manual mentions      |-Wuse-after-free is
                   |-Wuse-after-free but does   |documented in the wrong
                   |not document it further     |location
           Keywords|                            |documentation
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1

--- Comment #7 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Oh yes -Wuse-after-free documentation should be moved. 

There are some others which are also misplaced (Wuseless-cast)

[Bug c/111693] -Wuse-after-free is documented in the wrong location

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111693

--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #3)
> The easiest way to find documentation for an option is to look at the index
> located at:
> https://gcc.gnu.org/onlinedocs/gcc-13.2.0/gcc/Option-Index.html
> 
> And search for the option.

You should also be able to find it in the option summary:

https://gcc.gnu.org/onlinedocs/gcc-13.2.0/gcc/Option-Summary.html

But it's not there.

[Bug c/111693] -Wuse-after-free is documented in the wrong location

[egallager at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111693

Eric Gallager <egallager at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |egallager at gcc dot gnu.org
           See Also|                            |https://gcc.gnu.org/bugzill
                   |                            |a/show_bug.cgi?id=71283

--- Comment #9 from Eric Gallager <egallager at gcc dot gnu.org> ---
related: bug 71283

[Bug c/111693] -Wuse-after-free is documented in the wrong location

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111693

--- Comment #10 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Sandra Loosemore <sandra@gcc.gnu.org>:

https://gcc.gnu.org/g:25bb8a40abd91fccf9a59dd6518a7a283433dea3

commit r14-8173-g25bb8a40abd91fccf9a59dd6518a7a283433dea3
Author: Sandra Loosemore <sandra@codesourcery.com>
Date:   Wed Jan 17 04:41:52 2024 +0000

    Move docs for -Wuse-after-free and -Wuseless-cast [PR111693]

    These options were categorized as C++ options, but they apply to all
    C-family languages.

    gcc/ChangeLog
            PR c/111693
            * doc/invoke.texi (Option Summary): Move -Wuseless-cast
            from C++ Language Options to Warning Options.  Add entry for
            -Wuse-after-free.
            (C++ Dialect Options): Move -Wuse-after-free and -Wuseless-cast
            from here....
            (Warning Options): ...to here.  Minor copy-editing to fix typo
            and grammar.

[Bug c/111693] -Wuse-after-free is documented in the wrong location

[sandra at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111693

sandra at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED

--- Comment #11 from sandra at gcc dot gnu.org ---
Fixed.

[Bug c/111693] -Wuse-after-free is documented in the wrong location

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111693

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |14.0