Re: [Xen-devel] [XEN PATCH v3 14/23] xen/build: use new $(c_flags) and $(a_flags) instead of $(CFLAGS)

[Jan Beulich <jbeulich@xxxxxxxx>]

On 26.02.2020 12:33, Anthony PERARD wrote:
> --- a/xen/scripts/Kbuild.include
> +++ b/xen/scripts/Kbuild.include
> @@ -10,7 +10,7 @@ DEPS_INCLUDE = $(addsuffix .d2, $(basename $(wildcard 
> $(DEPS))))
>  # as-insn: Check whether assembler supports an instruction.
>  # Usage: cflags-y += $(call as-insn,CC FLAGS,"insn",option-yes,option-no)
>  as-insn = $(if $(shell echo 'void _(void) { asm volatile ( $(2) ); }' \
> -                       | $(filter-out -M% %.d -include 
> %/include/xen/config.h,$(1)) \
> +                       | $(filter-out -include %/include/xen/config.h,$(1)) \
>                                -c -x c -o /dev/null - 2>&1),$(4),$(3))

I'm sorry, while it was me to suggest this change - is this
correct? The variable to modify is a parameter of this macro,
i.e. things aren't limited to CFLAGS here. If we want to
disallow use with e.g. c_flags or anything derived from it,
then we should find some way to actually enforce this (like
dropping the respective parameter; I'm uncertain though whether
we wouldn't regret this if we ever got to the point where we
wanted to use a newer insn in a .S file).

Jan

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel