On Thu, 28 Jul 2016 22:30:43 -0400 Steven Rostedt <rost...@goodmis.org> wrote:
> On Thu, 28 Jul 2016 18:25:33 -0700 > Linus Torvalds <torva...@linux-foundation.org> wrote: > > > I tried something like that, but the CFLAGS games the tracing code > > does made my thing result in > > > > kernel/trace/Makefile:20: *** Recursive variable 'KBUILD_CFLAGS' > > references itself (eventually). Stop. > > > > but yes, if you have the magic fingers to make it work, limiting the > > -Wno-frame-address to just the tracing code sounds like the > > RightThing(tm). > > Take 2: > > It compiles for me, but I don't have a compiler that has that warning > to test with. See if this works. BTW, it looks like that last comma > before the ending parenthesis is not needed. Linus, did you get a chance to test this? I could send a formal patch if needed. I only have a 4.9 compiler, so I'm not seeing the warnings others have reported. -- Steve > > Signed-off-by: Steven Rostedt <rost...@goodmis.org> > --- > diff --git a/Makefile b/Makefile > index 393b615..d384848 100644 > --- a/Makefile > +++ b/Makefile > @@ -620,7 +620,6 @@ include arch/$(SRCARCH)/Makefile > > KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,) > KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,) > -KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,) > > ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE > KBUILD_CFLAGS += -Os > diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile > index 979e7bf..d0a1617 100644 > --- a/kernel/trace/Makefile > +++ b/kernel/trace/Makefile > @@ -1,4 +1,8 @@ > > +# We are fully aware of the dangers of __builtin_return_address() > +FRAME_CFLAGS := $(call cc-disable-warning,frame-address) > +KBUILD_CFLAGS += $(FRAME_CFLAGS) > + > # Do not instrument the tracer itself: > > ifdef CONFIG_FUNCTION_TRACER
