[Bug c/65213] New: Extend -Wmissing-declarations to variables

[Bug c/65213] New: Extend -Wmissing-declarations to variables

[eugene.zelenko at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65213

            Bug ID: 65213
           Summary: Extend -Wmissing-declarations to variables
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: eugene.zelenko at gmail dot com

Will be good idea to -Wmissing-declarations to variables. Global variable
should have extern declaration in header file, otherwise variable should be
static.

Clang detect such situations with -Wmissing-variable-declarations.

Same should be done for C++.

[Bug c/65213] Extend -Wmissing-declarations to variables [i.e. add -Wmissing-variable-declarations]

[egallager at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65213

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |egallager at gcc dot gnu.org

--- Comment #2 from Eric Gallager <egallager at gcc dot gnu.org> ---
Now that -fno-common is the default, having this flag would make it easier to
catch mis-declared variables that will turn into link errors at link time by
catching them at compile time instead, so I'd think it's a bit more important
now.

[Bug c/65213] Extend -Wmissing-declarations to variables [i.e. add -Wmissing-variable-declarations]

[egallager at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65213

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |patch
                URL|                            |https://gcc.gnu.org/piperma
                   |                            |il/gcc-patches/2023-June/62
                   |                            |1564.html

--- Comment #3 from Eric Gallager <egallager at gcc dot gnu.org> ---
A patch has been posted to the gcc-patches mailing list:
https://gcc.gnu.org/pipermail/gcc-patches/2023-June/621564.html

[Bug c/65213] Extend -Wmissing-declarations to variables [i.e. add -Wmissing-variable-declarations]

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65213

--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Joseph Myers <jsm28@gcc.gnu.org>:

https://gcc.gnu.org/g:ffc74822468a39324722eef4c4412ea3224ca976

commit r14-2888-gffc74822468a39324722eef4c4412ea3224ca976
Author: Hamza Mahfooz <someguy@effective-light.com>
Date:   Mon Jul 31 19:03:47 2023 +0000

    c: add -Wmissing-variable-declarations [PR65213]

    Resolves:
    PR c/65213 - Extend -Wmissing-declarations to variables [i.e. add
    -Wmissing-variable-declarations]

    gcc/c-family/ChangeLog:

            PR c/65213
            * c.opt (-Wmissing-variable-declarations): New option.

    gcc/c/ChangeLog:

            PR c/65213
            * c-decl.cc (start_decl): Handle
            -Wmissing-variable-declarations.

    gcc/ChangeLog:

            PR c/65213
            * doc/invoke.texi (-Wmissing-variable-declarations): Document
            new option.

    gcc/testsuite/ChangeLog:

            PR c/65213
            * gcc.dg/Wmissing-variable-declarations.c: New test.

    Signed-off-by: Hamza Mahfooz <someguy@effective-light.com>

[Bug c/65213] Extend -Wmissing-declarations to variables [i.e. add -Wmissing-variable-declarations]

[jsm28 at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65213

Joseph S. Myers <jsm28 at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
             Status|NEW                         |RESOLVED
   Target Milestone|---                         |14.0

--- Comment #5 from Joseph S. Myers <jsm28 at gcc dot gnu.org> ---
Implemented for GCC 14.

[Bug c/65213] Extend -Wmissing-declarations to variables [i.e. add -Wmissing-variable-declarations]

[ndesaulniers at google dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65213

Nick Desaulniers <ndesaulniers at google dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ndesaulniers at google dot com

--- Comment #6 from Nick Desaulniers <ndesaulniers at google dot com> ---
Thanks for implementing this!

I filed a follow up wrt to how this diagnostic interacts with `register`
storage variables.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110947 PTAL