Re: [XEN PATCH 15/15] build: remove Config.mk include from Rules.mk

[Jan Beulich <jbeulich@xxxxxxxx>]

On 23.05.2023 18:38, Anthony PERARD wrote:
> Everything needed to build the hypervisor should already be configured
> by "xen/Makefile", thus Config.mk shouldn't be needed.

"... by xen/Rules.mk." (Or else it sounds as if yo're removing its use
altogether.)

> --- a/xen/Makefile
> +++ b/xen/Makefile
> @@ -246,10 +246,14 @@ export TARGET_ARCH     := $(shell echo 
> $(XEN_TARGET_ARCH) | \
>                              sed -e 's/x86.*/x86/' -e s'/arm\(32\|64\)/arm/g' 
> \
>                                  -e s'/riscv.*/riscv/g')
>  
> +export XEN_COMPILE_ARCH XEN_TARGET_ARCH
>  export CONFIG_SHELL := $(SHELL)
>  export CC CXX LD NM OBJCOPY OBJDUMP ADDR2LINE
> +export CPP AR

For these two, could I talk you into editing the earlier line instead
of adding a new one?

> --- a/xen/scripts/Kbuild.include
> +++ b/xen/scripts/Kbuild.include
> @@ -8,6 +8,13 @@ empty   :=
>  space   := $(empty) $(empty)
>  space_escape := _-_SPACE_-_
>  pound   := \#
> +comma   := ,
> +open    := (
> +close   := )
> +
> +# fallbacks for GNU Make older than 3.81
> +realpath = $(wildcard $(foreach file,$(1),$(shell cd -P $(dir $(file)) && 
> echo "$$PWD/$(notdir $(file))")))
> +or       = $(if $(strip $(1)),$(1),$(if $(strip $(2)),$(2),$(if $(strip 
> $(3)),$(3),$(if $(strip $(4)),$(4)))))
>  
>  ###
>  # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o

As long as they're the same, the collision with Config.mk's will be
benign (for xen/Makefile), but I wonder whether, along the lines of
the earlier patch, these wouldn't better be extracted into e.g.
config/fallbacks.mk. (Whether the single-character macros are also
extracted into somewhere is of less importance to me, at least right
now.)

Jan