Re: [Qemu-devel] [PATCH 1/2] build: simplify and fix fix-obj-vars

[Fam Zheng <famz@redhat.com>]

On Thu, 05/08 15:08, Paolo Bonzini wrote:
> fix-obj-vars has the undesired side effect of breaking -cflags
> -objs and -libs variables in the toplevel Makefile.objs.  The
> variables in the toplevel Makefile.objs do not need any fix,
> so fix-obj-vars need not do anything.
> 
> Since we are touching it, remove the now unnecessary $(if)
> in the callers.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  rules.mak | 15 ++++++++-------
>  1 file changed, 8 insertions(+), 7 deletions(-)
> 
> diff --git a/rules.mak b/rules.mak
> index c0c3d86..26014c5 100644
> --- a/rules.mak
> +++ b/rules.mak
> @@ -175,16 +175,17 @@ $(eval save-$2-$1 :=)
>  endef
>  
>  define fix-obj-vars
> -$(foreach v,$($1), \
> +$(if $2,
> +  $(foreach v,$($1), \

Not very consistent in indentation. BTW what's the right space/tab style to
use in Makefiles for multi-line macros like this?

>  	$(if $($v-cflags), \
> -		$(eval $2$v-cflags := $($v-cflags)) \
> +		$(eval $2/$v-cflags := $($v-cflags)) \
>  		$(eval $v-cflags := )) \
>  	$(if $($v-libs), \
> -		$(eval $2$v-libs := $($v-libs)) \
> +		$(eval $2/$v-libs := $($v-libs)) \
>  		$(eval $v-libs := )) \
>  	$(if $($v-objs), \
> -		$(eval $2$v-objs := $(addprefix $2,$($v-objs))) \
> -		$(eval $v-objs := )))
> +		$(eval $2/$v-objs := $(addprefix $2/,$($v-objs))) \
> +		$(eval $v-objs := ))))
>  endef
>  
>  define unnest-dir
> @@ -192,7 +193,7 @@ $(foreach var,$(nested-vars),$(call push-var,$(var),$1/))
>  $(eval obj-parent-$1 := $(obj))
>  $(eval obj := $(if $(obj),$(obj)/$1,$1))
>  $(eval include $(SRC_PATH)/$1/Makefile.objs)
> -$(foreach v,$(nested-vars),$(call fix-obj-vars,$v,$(if $(obj),$(obj)/)))
> +$(foreach v,$(nested-vars),$(call fix-obj-vars,$v,$(obj)))
>  $(eval obj := $(obj-parent-$1))
>  $(eval obj-parent-$1 := )
>  $(foreach var,$(nested-vars),$(call pop-var,$(var),$1/))
> @@ -228,7 +229,7 @@ endef
>  define unnest-vars
>  $(eval obj := $1)
>  $(eval nested-vars := $2)
> -$(foreach v,$(nested-vars),$(call fix-obj-vars,$v,$(if $(obj),$(obj)/)))

I'm not sure about this removed line since it's not in master, maybe you missed
a patch to squash?

> +$(foreach v,$(nested-vars),$(call fix-obj-vars,$v,$(obj)))

But the new line looks good.

Thanks,
Reviewed-by: Fam Zheng <famz@redhat.com>

>  $(eval old-nested-dirs := )
>  $(call unnest-vars-1)
>  $(if $1,$(foreach v,$(nested-vars),$(eval \
> -- 
> 1.8.3.1
> 
> 
>