lib/unused-parameter.h

   1 /* A C macro for declaring that specific function parameters are not used.
   2    Copyright (C) 2008-2019 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify it
   5    under the terms of the GNU Lesser General Public License as published
   6    by the Free Software Foundation; either version 2 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* _GL_UNUSED_PARAMETER is a marker that can be appended to function parameter
  18    declarations for parameters that are not used.  This helps to reduce
  19    warnings, such as from GCC -Wunused-parameter.  The syntax is as follows:
  20        type param _GL_UNUSED_PARAMETER
  21    or more generally
  22        param_decl _GL_UNUSED_PARAMETER
  23    For example:
  24        int param _GL_UNUSED_PARAMETER
  25        int *(*param)(void) _GL_UNUSED_PARAMETER
  26    Other possible, but obscure and discouraged syntaxes:
  27        int _GL_UNUSED_PARAMETER *(*param)(void)
  28        _GL_UNUSED_PARAMETER int *(*param)(void)
  29  */
  30 #ifndef _GL_UNUSED_PARAMETER
  31 # if __GNUC__ >= 3 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7)
  32 #  define _GL_UNUSED_PARAMETER __attribute__ ((__unused__))
  33 # else
  34 #  define _GL_UNUSED_PARAMETER
  35 # endif
  36 #endif