kconfig: suppress "configuration written to .config" for syncconfig

The top-level Makefile invokes "make syncconfig" when necessary.
Then, Kconfig displays the following message when .config is updated.

  #
  # configuration written to .config
  #

It is distracting because "make syncconfig" happens during the build
stage, and does nothing important in most cases.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>

diff --git a/config/conf.c b/config/conf.c
index 2f968e25b3c0c8bf40972ccd324815c6cc5d4391..c19af7d7d99d7bc8b3ebf717dd5a13ac8f66a9f8 100644 (file)
--- a/config/conf.c
+++ b/config/conf.c
@@ -494,6 +494,14 @@ int main(int ac, char **av)
                }
                input_mode = (enum input_mode)opt;
                switch (opt) {
+               case syncconfig:
+                       /*
+                        * syncconfig is invoked during the build stage.
+                        * Suppress distracting "configuration written to ..."
+                        */
+                       conf_set_message_callback(NULL);
+                        sync_kconfig = 1;
+                       break
                case defconfig:
                case savedefconfig:
                        defconfig_file = optarg;