[PATCH 3.2 056/104] kconfig.h: use __is_defined() to check if MODULE is defined

[Ben Hutchings]

3.2.101-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>

commit 4f920843d248946545415c1bf6120942048708ed upstream.

The macro MODULE is not a config option, it is a per-file build
option.  So, config_enabled(MODULE) is not sensible.  (There is
another case in include/linux/export.h, where config_enabled() is
used against a non-config option.)

This commit renames some macros in include/linux/kconfig.h for the
use for non-config macros and replaces config_enabled(MODULE) with
__is_defined(MODULE).

I am keeping config_enabled() because it is still referenced from
some places, but I expect it would be deprecated in the future.

Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Signed-off-by: Michal Marek <mmarek@xxxxxxxx>
[bwh: Backported to 3.2: drop change in IS_REACHABLE()]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
--- a/include/linux/kconfig.h
+++ b/include/linux/kconfig.h
@@ -17,10 +17,11 @@
  * the last step cherry picks the 2nd arg, we get a zero.
  */
 #define __ARG_PLACEHOLDER_1 0,
-#define config_enabled(cfg) _config_enabled(cfg)
-#define _config_enabled(value) __config_enabled(__ARG_PLACEHOLDER_##value)
-#define __config_enabled(arg1_or_junk) ___config_enabled(arg1_or_junk 1, 0)
-#define ___config_enabled(__ignored, val, ...) val
+#define config_enabled(cfg)		___is_defined(cfg)
+#define __is_defined(x)			___is_defined(x)
+#define ___is_defined(val)		____is_defined(__ARG_PLACEHOLDER_##val)
+#define ____is_defined(arg1_or_junk)	__take_second_arg(arg1_or_junk 1, 0)
+#define __take_second_arg(__ignored, val, ...) val
 
 /*
  * IS_ENABLED(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y' or 'm',