[viro-vfs:work.fd 28/39] include/linux/cleanup.h:111:21: error: function declaration isn't a prototype

[viro-vfs:work.fd 28/39] include/linux/cleanup.h:111:21: error: function declaration isn't a prototype

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git work.fd
head:   154eb19a802fdf8629273d414dbeb31eccb61587
commit: a5027b86a79716e98fe0b8e1247743dfb5a5c080 [28/39] switch spufs_calls_{get,put}() to CLASS() use
config: powerpc-allmodconfig (https://download.01.org/0day-ci/archive/20240729/202407292309.QXlzRsZS-lkp@intel.com/config)
compiler: powerpc64-linux-gcc (GCC) 14.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240729/202407292309.QXlzRsZS-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202407292309.QXlzRsZS-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from include/linux/file.h:14,
                    from arch/powerpc/platforms/cell/spu_syscalls.c:10:
>> include/linux/cleanup.h:111:21: error: function declaration isn't a prototype [-Werror=strict-prototypes]
     111 | static inline _type class_##_name##_constructor(_init_args)             \
         |                     ^~~~~~
   arch/powerpc/platforms/cell/spu_syscalls.c:59:1: note: in expansion of macro 'DEFINE_CLASS'
      59 | DEFINE_CLASS(spufs_calls, struct spufs_calls *, spufs_calls_put(_T), spufs_calls_get())
         | ^~~~~~~~~~~~
   cc1: some warnings being treated as errors


vim +111 include/linux/cleanup.h

54da6a0924311c Peter Zijlstra 2023-05-26   82  
54da6a0924311c Peter Zijlstra 2023-05-26   83  
54da6a0924311c Peter Zijlstra 2023-05-26   84  /*
54da6a0924311c Peter Zijlstra 2023-05-26   85   * DEFINE_CLASS(name, type, exit, init, init_args...):
54da6a0924311c Peter Zijlstra 2023-05-26   86   *	helper to define the destructor and constructor for a type.
54da6a0924311c Peter Zijlstra 2023-05-26   87   *	@exit is an expression using '_T' -- similar to FREE above.
54da6a0924311c Peter Zijlstra 2023-05-26   88   *	@init is an expression in @init_args resulting in @type
54da6a0924311c Peter Zijlstra 2023-05-26   89   *
54da6a0924311c Peter Zijlstra 2023-05-26   90   * EXTEND_CLASS(name, ext, init, init_args...):
54da6a0924311c Peter Zijlstra 2023-05-26   91   *	extends class @name to @name@ext with the new constructor
54da6a0924311c Peter Zijlstra 2023-05-26   92   *
54da6a0924311c Peter Zijlstra 2023-05-26   93   * CLASS(name, var)(args...):
54da6a0924311c Peter Zijlstra 2023-05-26   94   *	declare the variable @var as an instance of the named class
54da6a0924311c Peter Zijlstra 2023-05-26   95   *
54da6a0924311c Peter Zijlstra 2023-05-26   96   * Ex.
54da6a0924311c Peter Zijlstra 2023-05-26   97   *
54da6a0924311c Peter Zijlstra 2023-05-26   98   * DEFINE_CLASS(fdget, struct fd, fdput(_T), fdget(fd), int fd)
54da6a0924311c Peter Zijlstra 2023-05-26   99   *
54da6a0924311c Peter Zijlstra 2023-05-26  100   *	CLASS(fdget, f)(fd);
a825760957e3aa Al Viro        2024-05-31  101   *	if (!fd_file(f))
54da6a0924311c Peter Zijlstra 2023-05-26  102   *		return -EBADF;
54da6a0924311c Peter Zijlstra 2023-05-26  103   *
54da6a0924311c Peter Zijlstra 2023-05-26  104   *	// use 'f' without concern
54da6a0924311c Peter Zijlstra 2023-05-26  105   */
54da6a0924311c Peter Zijlstra 2023-05-26  106  
54da6a0924311c Peter Zijlstra 2023-05-26  107  #define DEFINE_CLASS(_name, _type, _exit, _init, _init_args...)		\
54da6a0924311c Peter Zijlstra 2023-05-26  108  typedef _type class_##_name##_t;					\
54da6a0924311c Peter Zijlstra 2023-05-26  109  static inline void class_##_name##_destructor(_type *p)			\
54da6a0924311c Peter Zijlstra 2023-05-26  110  { _type _T = *p; _exit; }						\
54da6a0924311c Peter Zijlstra 2023-05-26 @111  static inline _type class_##_name##_constructor(_init_args)		\
54da6a0924311c Peter Zijlstra 2023-05-26  112  { _type t = _init; return t; }
54da6a0924311c Peter Zijlstra 2023-05-26  113  

:::::: The code at line 111 was first introduced by commit
:::::: 54da6a0924311c7cf5015533991e44fb8eb12773 locking: Introduce __cleanup() based infrastructure

:::::: TO: Peter Zijlstra <peterz@infradead.org>
:::::: CC: Peter Zijlstra <peterz@infradead.org>

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [viro-vfs:work.fd 28/39] include/linux/cleanup.h:111:21: error: function declaration isn't a prototype

[Al Viro]

On Mon, Jul 29, 2024 at 11:07:02PM +0800, kernel test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git work.fd
> head:   154eb19a802fdf8629273d414dbeb31eccb61587
> commit: a5027b86a79716e98fe0b8e1247743dfb5a5c080 [28/39] switch spufs_calls_{get,put}() to CLASS() use
> config: powerpc-allmodconfig (https://download.01.org/0day-ci/archive/20240729/202407292309.QXlzRsZS-lkp@intel.com/config)
> compiler: powerpc64-linux-gcc (GCC) 14.1.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240729/202407292309.QXlzRsZS-lkp@intel.com/reproduce)
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202407292309.QXlzRsZS-lkp@intel.com/
> 
> All errors (new ones prefixed by >>):
> 
>    In file included from include/linux/file.h:14,
>                     from arch/powerpc/platforms/cell/spu_syscalls.c:10:
> >> include/linux/cleanup.h:111:21: error: function declaration isn't a prototype [-Werror=strict-prototypes]
>      111 | static inline _type class_##_name##_constructor(_init_args)             \
>          |                     ^~~~~~
>    arch/powerpc/platforms/cell/spu_syscalls.c:59:1: note: in expansion of macro 'DEFINE_CLASS'
>       59 | DEFINE_CLASS(spufs_calls, struct spufs_calls *, spufs_calls_put(_T), spufs_calls_get())
>          | ^~~~~~~~~~~~
>    cc1: some warnings being treated as errors

Bollocks galore:

1) gcc does not catch e.g.
	if (foo)
		goto l;
	void *p __free(kfree) = NULL;
	...
l:
	...
and quietly passes an uninitialized value to kfree().  clang catches that.

2) clang, OTOH, does not feel obliged to object against DEFINE_CLASS with
4 arguments and constructor that takes no arguments at all.  gcc produces
the splat above...

Joy...