Commit 29bd0cac authored by Utkarsh Verma's avatar Utkarsh Verma Committed by Jonathan Corbet
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Documentation: checkpatch: Add TRAILING_SEMICOLON message 



Add a new message type TRAILING_SEMICOLON for the macro definitions
that conclude with a semicolon.

Suggested-by: default avatarLukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: default avatarUtkarsh Verma <utkarshverma294@gmail.com>
Link: https://lore.kernel.org/r/20210904074201.13532-1-utkarshverma294@gmail.com


Signed-off-by: default avatarJonathan Corbet <corbet@lwn.net>
parent d9548979

Documentation/dev-tools/checkpatch.rst

+21 −0
Original line number Diff line number Diff line
@@ -851,6 +851,27 @@ Macros, Attributes and Symbols 
    Use the `fallthrough;` pseudo keyword instead of

    `/* fallthrough */` like comments.



  **TRAILING_SEMICOLON**

    Macro definition should not end with a semicolon. The macro

    invocation style should be consistent with function calls.

    This can prevent any unexpected code paths::



      #define MAC do_something;



    If this macro is used within a if else statement, like::



      if (some_condition)

              MAC;



      else

              do_something;



    Then there would be a compilation error, because when the macro is

    expanded there are two trailing semicolons, so the else branch gets

    orphaned.



    See: https://lore.kernel.org/lkml/1399671106.2912.21.camel@joe-AO725/



  **WEAK_DECLARATION**

    Using weak declarations like __attribute__((weak)) or __weak

    can have unintended link defects.  Avoid using them.