tinc/m4/attribute.m4
2019-08-26 13:44:52 +02:00

25 lines
663 B
Text

dnl Check to find out whether function attributes are supported.
dnl If they are not, #define them to be nothing.
AC_DEFUN([tinc_ATTRIBUTE],
[
AC_CACHE_CHECK([for working $1 attribute], tinc_cv_attribute_$1,
[
tempcflags="$CFLAGS"
CFLAGS="$CFLAGS -Wall -Werror"
AC_COMPILE_IFELSE(
[AC_LANG_SOURCE(
[void *test(void) __attribute__ (($1));
void *test(void) { return (void *)0; }
],
)],
[tinc_cv_attribute_$1=yes],
[tinc_cv_attribute_$1=no]
)
CFLAGS="$tempcflags"
])
if test ${tinc_cv_attribute_$1} = no; then
AC_DEFINE([$1], [], [Defined if the $1 attribute is not supported.])
fi
])