[PATCH v2] Makefile: Add option to disable gcc automatic inlining

[Ezequiel Garcia <elezegarcia@gmail.com>]

The new option is CONFIG_CC_DISABLE_AUTO_INLINE and it's
located at:
  * Kernel hacking
    * Disable gcc automatic inlining

This option appends this options CFLAGS:

-fno-default-inline
-fno-inline
-fno-inline-small-functions
-fno-indirect-inlining
-fno-inline-functions-called-once

It's still not clear which of these really work and which doesn't.
Just in case, just disable all of them.

Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com>
---
Changes from v1:
 * Change define name to CONFIG_CC_XXX
 * Disable all options that refer to inlining

This work is part of CELF Workgroup Project:
"Kernel_dynamic_memory_allocation_tracking_and_reduction":
http://elinux.org/Kernel_dynamic_memory_allocation_tracking_and_reduction

 Makefile             |    8 ++++++++
 kernel/trace/Kconfig |    4 ++++
 2 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/Makefile b/Makefile
index ddf5be9..3169603 100644
--- a/Makefile
+++ b/Makefile
@@ -561,6 +561,14 @@ else
 KBUILD_CFLAGS	+= -O2
 endif
 
+ifdef CONFIG_CC_DISABLE_AUTO_INLINE
+KBUILD_CFLAGS	+= -fno-default-inline \
+		   -fno-inline \
+		   -fno-inline-small-functions \
+		   -fno-indirect-inlining \
+		   -fno-inline-functions-called-once
+endif
+
 include $(srctree)/arch/$(SRCARCH)/Makefile
 
 ifdef CONFIG_READABLE_ASM
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 8c4c070..144da36 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -128,6 +128,10 @@ config TRACING_SUPPORT
 	depends on STACKTRACE_SUPPORT
 	default y
 
+config CC_DISABLE_AUTO_INLINE
+	bool "Disable gcc automatic inlining"
+	default n
+
 if TRACING_SUPPORT
 
 menuconfig FTRACE
-- 
1.7.8.6