[PATCH] Turn off sibling call optimization w/ frame pointers

Frame pointers are supposed to enable debuggers to reliably tell where a
call comes from.  That is defeated by GCC's sibling call optimization (aka
tail recursion elimination).

This patch turns this optimization off when compiling with frame pointers.
Signed-Off-By: NMatthias Urlichs <smurf@smurf.noris.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Makefile

@@ -518,7 +518,7 @@ CFLAGS		+= $(call add-align,CONFIG_CC_ALIGN_LOOPS,-loops)
 CFLAGS		+= $(call add-align,CONFIG_CC_ALIGN_JUMPS,-jumps)
 
 ifdef CONFIG_FRAME_POINTER
-CFLAGS		+= -fno-omit-frame-pointer
+CFLAGS		+= -fno-omit-frame-pointer $(call cc-option,-fno-optimize-sibling-calls,)
 else
 CFLAGS		+= -fomit-frame-pointer
 endif