Avoid -Wunused-parameter warnings in public gnulib header files.

[gnulib.git] / m4 / gnulib-common.m4

diff --git a/m4/gnulib-common.m4 b/m4/gnulib-common.m4
index 34d91c7..c73db14 100644 (file)
--- a/m4/gnulib-common.m4
+++ b/m4/gnulib-common.m4
@@ -1,4 +1,4 @@
-# gnulib-common.m4 serial 5
+# gnulib-common.m4 serial 6
 dnl Copyright (C) 2007-2008 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -21,6 +21,16 @@ AC_DEFUN([gl_COMMON_BODY], [
 #if defined __APPLE__ && defined __MACH__ && __APPLE_CC__ >= 5465 && !defined __cplusplus && __STDC_VERSION__ >= 199901L && !defined __GNUC_STDC_INLINE__
 # define __GNUC_STDC_INLINE__ 1
 #endif])
+  AH_VERBATIM([unused_parameter],
+[/* Define as a marker that can be attached to function parameter declarations
+   for parameters that are not used.  This helps to reduce warnings, such as
+   from GCC -Wunused-parameter.  */
+#if __GNUC__ >= 3 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7)
+# define _UNUSED_PARAMETER_ __attribute__ ((__unused__))
+#else
+# define _UNUSED_PARAMETER_
+#endif
+])
 ])
 
 # gl_MODULE_INDICATOR([modulename])