@@ -7,6 +7,7 @@ quote := "
squote := '
empty :=
space := $(empty) $(empty)
+space_escape := _-_SPACE_-_
###
# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
@@ -226,10 +227,10 @@ objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))
# See Documentation/kbuild/makefiles.txt for more info
ifneq ($(KBUILD_NOCMDDEP),1)
-# Check if both arguments has same arguments. Result is empty string if equal.
-# User may override this check using make KBUILD_NOCMDDEP=1
-arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \
- $(filter-out $(cmd_$@), $(cmd_$(1))) )
+# Check if both arguments are the same including their order. Result is empty
+# string if equal. User may override this check using make KBUILD_NOCMDDEP=1
+arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \
+ $(subst $(space),$(space_escape),$(strip $(cmd_$1))))
else
arg-check = $(if $(strip $(cmd_$@)),,1)
endif
@@ -341,8 +342,6 @@ endif
#
###############################################################################
#
-space_escape := %%%SPACE%%%
-#
define config_filename
ifneq ($$(CONFIG_$(1)),"")
$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1)))))))
Currently, arg-check is implemented as follows: arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \ $(filter-out $(cmd_$@), $(cmd_$(1))) ) This does not care about the order of arguments that appear in $(cmd_$(1)) and $(cmd_$@). So, if_changed and friends never rebuild the target if only the argument order is changed. This is a problem when the link order is changed. Apparently, obj-y += foo.o obj-y += bar.o and obj-y += bar.o obj-y += foo.o should be distinguished because the link order determines the probe order of drivers. So, built-in.o should be rebuilt when the order of objects is changed. This commit fixes arg-check to compare the old/current commands including the argument order. Of course, this change has a side effect; Kbuild will react to the change of compile option order. For example, "-DFOO -DBAR" and "-DBAR -DFOO" should give no difference to the build result, but false positive should be better than false negative. I am moving space_escape to the top of Kbuild.include just for a matter of preference. In practical terms, space_escape can be defined after arg-check because arg-check uses "=" flavor, not ":=". Having said that, collecting convenient variables in one place makes sense from the point of readability. Chaining "%%%SPACE%%%" to "_-_SPACE_-_" is also a matter of taste at this point. Actually, it can be arbitrary as long as it is an unlikely used string. The only problem I see in "%%%SPACE%%%" is that "%" is a special character in "$(patsubst ...)" context. This commit just uses "$(subst ...)" for arg-check, but I am fixing it now in case we might want to use it in $(patsubst ...) context in the future. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> --- Changes in v2: - V1 did not work. Change the approach. scripts/Kbuild.include | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) -- 1.9.1