[PATCH] Add CONFIG_HEADERS_CHECK option to automatically run 'make headers_check'

In order to encourage people to notice when they break the exported
headers, add a config option which automatically runs the sanity checks
when building vmlinux.  That way, those who use allyesconfig will notice
failures.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 2d7cb0d..8fd2dbf 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -371,6 +371,19 @@
 	  become the default in the future, until then this option is there to
 	  test gcc for this.
 
+config HEADERS_CHECK
+	bool "Run 'make headers_check' when building vmlinux"
+	help
+	  This option will extract the user-visible kernel headers whenever
+	  building the kernel, and will run basic sanity checks on them to
+	  ensure that exported files do not attempt to include files which
+	  were not exported, etc.
+
+	  If you're making modifications to header files which are
+	  relevant for userspace, say 'Y', and check the headers
+	  exported to $(INSTALL_HDR_PATH) (usually 'usr/include' in
+	  your build tree), to make sure they're suitable.
+
 config RCU_TORTURE_TEST
 	tristate "torture tests for RCU"
 	depends on DEBUG_KERNEL