Linux 4.0 compat: bdi_setup_and_register() __must_check

Explicitly disable the unused by variable warnings by setting
__attribute__((unused)) for bdi_setup_and_register().  This is
required because the function is defined with the __must_check
attribute.

Signed-off-by: Bill McGonigle <bill-github.com-public1@bfccomputing.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3141

diff --git a/config/kernel-bdi-setup-and-register.m4 b/config/kernel-bdi-setup-and-register.m4
index f13d1fe53dda15806e611b138e916b4c453b3eca..11eefb28bfcaf4b7b39e67c69ed9d1b2b37d0f49 100644 (file)
--- a/config/kernel-bdi-setup-and-register.m4
+++ b/config/kernel-bdi-setup-and-register.m4
@@ -10,7 +10,8 @@ AC_DEFUN([ZFS_AC_KERNEL_BDI_SETUP_AND_REGISTER], [
        ], [
                struct backing_dev_info bdi;
                char *name = "bdi";
-               (void) bdi_setup_and_register(&bdi, name);
+               int error __attribute__((unused)) =
+                   bdi_setup_and_register(&bdi, name);
        ], [bdi_setup_and_register], [mm/backing-dev.c], [
                AC_MSG_RESULT(yes)
                AC_DEFINE(HAVE_2ARGS_BDI_SETUP_AND_REGISTER, 1,
@@ -24,7 +25,8 @@ AC_DEFUN([ZFS_AC_KERNEL_BDI_SETUP_AND_REGISTER], [
                        struct backing_dev_info bdi;
                        char *name = "bdi";
                        unsigned int cap = BDI_CAP_MAP_COPY;
-                       (void) bdi_setup_and_register(&bdi, name, cap);
+                       int error __attribute__((unused)) =
+                           bdi_setup_and_register(&bdi, name, cap);
                ], [bdi_setup_and_register], [mm/backing-dev.c], [
                        AC_MSG_RESULT(yes)
                        AC_DEFINE(HAVE_3ARGS_BDI_SETUP_AND_REGISTER, 1,