kbuild: sort hostprogs before passing it to ifneq

The conditional:

  ifneq ($(hostprogs),)

... is evaluated to true if $(hostprogs) does not contain any word but
whitespace characters.

  ifneq ($(strip $(hostprogs)),)

... is a safe way to avoid interpreting whitespace as a non-empty value,
but I'd rather want to use the side-effect of $(sort ...) to do the
equivalent.

$(sort ...) is used in scripts/Makefile.host in order to drop duplication
in $(hostprogs). It is also useful to strip excessive spaces.

Move $(sort ...) before evaluating the ifneq.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This commit is contained in:
Masahiro Yamada 2020-07-29 12:15:37 +09:00
parent 42640b134b
commit 85569d19d0
2 changed files with 8 additions and 7 deletions

View File

@ -45,12 +45,15 @@ include $(kbuild-file)
include scripts/Makefile.lib
# Do not include hostprogs rules unless needed
# Do not include hostprogs rules unless needed.
# $(sort ...) is used here to remove duplicated words and excessive spaces.
hostprogs := $(sort $(hostprogs))
ifneq ($(hostprogs),)
include scripts/Makefile.host
endif
# Do not include userprogs rules unless needed.
# $(sort ...) is used here to remove duplicated words and excessive spaces.
userprogs := $(sort $(userprogs))
ifneq ($(userprogs),)
include scripts/Makefile.userprogs

View File

@ -38,24 +38,22 @@ $(obj)/%.tab.c $(obj)/%.tab.h: $(src)/%.y FORCE
# Will compile qconf as a C++ program, and menu as a C program.
# They are linked as C++ code to the executable qconf
__hostprogs := $(sort $(hostprogs))
# C code
# Executables compiled from a single .c file
host-csingle := $(foreach m,$(__hostprogs), \
host-csingle := $(foreach m,$(hostprogs), \
$(if $($(m)-objs)$($(m)-cxxobjs),,$(m)))
# C executables linked based on several .o files
host-cmulti := $(foreach m,$(__hostprogs),\
host-cmulti := $(foreach m,$(hostprogs),\
$(if $($(m)-cxxobjs),,$(if $($(m)-objs),$(m))))
# Object (.o) files compiled from .c files
host-cobjs := $(sort $(foreach m,$(__hostprogs),$($(m)-objs)))
host-cobjs := $(sort $(foreach m,$(hostprogs),$($(m)-objs)))
# C++ code
# C++ executables compiled from at least one .cc file
# and zero or more .c files
host-cxxmulti := $(foreach m,$(__hostprogs),$(if $($(m)-cxxobjs),$(m)))
host-cxxmulti := $(foreach m,$(hostprogs),$(if $($(m)-cxxobjs),$(m)))
# C++ Object (.o) files compiled from .cc files
host-cxxobjs := $(sort $(foreach m,$(host-cxxmulti),$($(m)-cxxobjs)))