ax_c___attribute__

Provides a test for the compiler support of __attribute__ extensions. Defines HAVE___ATTRIBUTE__ if it is found.

AC_DEFUN([AX_C___ATTRIBUTE__], [
  AC_CACHE_CHECK([for __attribute__], [ax_cv___attribute__],
    [AC_COMPILE_IFELSE(
      [AC_LANG_PROGRAM(
        [[#include <stdlib.h>
          static void foo(void) __attribute__ ((unused));
          static void
          foo(void) {
              exit(1);
          }
        ]], [])],
      [ax_cv___attribute__=yes],
      [ax_cv___attribute__=no]
    )
  ])
  if test "$ax_cv___attribute__" = "yes"; then
    AC_DEFINE([HAVE___ATTRIBUTE__], 1, [define if your compiler has __attribute__])
  fi
])

Copyright © 2007 Stepan Kasal <skasal@redhat.com>
Copyright © 2007 Christian Haggstrom <chm@c00.info>
Copyright © 2007 Ryan McCabe <ryan@numb.org>

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