On Mon, 13 Aug 2018 11:54:06 +0100 Julien Thierry <julien.thierry@xxxxxxx> wrote: > > --- a/arch/arm64/Makefile > > +++ b/arch/arm64/Makefile > > @@ -78,6 +78,15 @@ ifeq ($(CONFIG_ARM64_MODULE_PLTS),y) > > KBUILD_LDFLAGS_MODULE += -T $(srctree)/arch/arm64/kernel/module.lds > > endif > > > > +ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS > > + CC_FLAGS_FTRACE := -fpatchable-function-entry=2 > > + KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY > > + ifeq ($(call cc-option,-fpatchable-function-entry=2),) > > + $(warning Cannot use CONFIG_DYNAMIC_FTRACE_WITH_REGS: \ > > + -fpatchable-function-entry not supported by compiler) > > Shouldn't this be an error? The option -fpatchable-function-entry has > been added to the CC_FLAGS_FTRACE, so any call to the compiler is gonna > break anyway. Or am I missing something? I'm guessing this adds a more informative message on that error. One will know why -fpatchable-function-entry was added to the CFLAGS. I'm for more informative error messages being a victim of poor error messages causing me to dig deep into the guts of the build infrastructure to figure out simple issues. -- Steve
