| Message ID | 1503209051-16477-1-git-send-email-yamada.masahiro@socionext.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sun, Aug 20, 2017 at 03:04:11PM +0900, Masahiro Yamada wrote: > Kbuild conventionally uses $(shell cd ... && /bin/pwd) idiom to get > the absolute path of the directory because GNU Make 3.80, the minimal > supported version at that time, did not support $(abspath ...) or > $(realpath ...). > > Commit 37d69ee30808 ("docs: bump minimal GNU Make version to 3.81") > dropped the GNU Make 3.80 support, so we are now allowed to use those > make-builtin helpers. > > This conversion will provide better portability without relying on > the pwd command or its location /bin/pwd. > > I am intentionally using $(realpath ...) instead $(abspath ...) in > some places. The difference between the two is $(realpath ...) > returns an empty string if the given path does not exist. It is > convenient in places where we need to error-out if the makefile fails > to create an output directory. > > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> > --- > > Makefile | 12 ++++++------ > scripts/gdb/linux/Makefile | 2 +- > tools/power/cpupower/Makefile | 2 +- > tools/scripts/Makefile.include | 6 +++--- > 4 files changed, 11 insertions(+), 11 deletions(-) This looks very similar to a patch I had written a long time ago: Acked-by: Thierry Reding <treding@nvidia.com>
2017-08-21 17:49 GMT+09:00 Thierry Reding <treding@nvidia.com>: > On Sun, Aug 20, 2017 at 03:04:11PM +0900, Masahiro Yamada wrote: >> Kbuild conventionally uses $(shell cd ... && /bin/pwd) idiom to get >> the absolute path of the directory because GNU Make 3.80, the minimal >> supported version at that time, did not support $(abspath ...) or >> $(realpath ...). >> >> Commit 37d69ee30808 ("docs: bump minimal GNU Make version to 3.81") >> dropped the GNU Make 3.80 support, so we are now allowed to use those >> make-builtin helpers. >> >> This conversion will provide better portability without relying on >> the pwd command or its location /bin/pwd. >> >> I am intentionally using $(realpath ...) instead $(abspath ...) in >> some places. The difference between the two is $(realpath ...) >> returns an empty string if the given path does not exist. It is >> convenient in places where we need to error-out if the makefile fails >> to create an output directory. >> >> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> >> --- >> >> Makefile | 12 ++++++------ >> scripts/gdb/linux/Makefile | 2 +- >> tools/power/cpupower/Makefile | 2 +- >> tools/scripts/Makefile.include | 6 +++--- >> 4 files changed, 11 insertions(+), 11 deletions(-) > > This looks very similar to a patch I had written a long time ago: > > Acked-by: Thierry Reding <treding@nvidia.com> Yup. Three month ago, I sent a reminder to you, but I did not get a response. https://lkml.org/lkml/2017/5/18/1370 This time, Bjorn sent a patch to replace /bin/pwd with pwd. I asked him to use $(abspath ...) / $(realpath ...), but he did not like to do it. https://patchwork.kernel.org/patch/9859591/ So, I am doing it by myself.
2017-08-21 18:04 GMT+09:00 Masahiro Yamada <yamada.masahiro@socionext.com>: > 2017-08-21 17:49 GMT+09:00 Thierry Reding <treding@nvidia.com>: >> On Sun, Aug 20, 2017 at 03:04:11PM +0900, Masahiro Yamada wrote: >>> Kbuild conventionally uses $(shell cd ... && /bin/pwd) idiom to get >>> the absolute path of the directory because GNU Make 3.80, the minimal >>> supported version at that time, did not support $(abspath ...) or >>> $(realpath ...). >>> >>> Commit 37d69ee30808 ("docs: bump minimal GNU Make version to 3.81") >>> dropped the GNU Make 3.80 support, so we are now allowed to use those >>> make-builtin helpers. >>> >>> This conversion will provide better portability without relying on >>> the pwd command or its location /bin/pwd. >>> >>> I am intentionally using $(realpath ...) instead $(abspath ...) in >>> some places. The difference between the two is $(realpath ...) >>> returns an empty string if the given path does not exist. It is >>> convenient in places where we need to error-out if the makefile fails >>> to create an output directory. >>> >>> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> > Applied to linux-kbuild. -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Makefile b/Makefile index 90da7bdc3f45..dfb6c88ea859 100644 --- a/Makefile +++ b/Makefile @@ -130,8 +130,8 @@ endif ifneq ($(KBUILD_OUTPUT),) # check that the output directory actually exists saved-output := $(KBUILD_OUTPUT) -KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \ - && /bin/pwd) +$(shell [ -d $(KBUILD_OUTPUT) ] || mkdir -p $(KBUILD_OUTPUT)) +KBUILD_OUTPUT := $(realpath $(KBUILD_OUTPUT)) $(if $(KBUILD_OUTPUT),, \ $(error failed to create output directory "$(saved-output)")) @@ -978,7 +978,7 @@ ifdef CONFIG_HEADERS_CHECK $(Q)$(MAKE) -f $(srctree)/Makefile headers_check endif ifdef CONFIG_GDB_SCRIPTS - $(Q)ln -fsn `cd $(srctree) && /bin/pwd`/scripts/gdb/vmlinux-gdb.py + $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py) endif ifdef CONFIG_TRIM_UNUSED_KSYMS $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \ @@ -1237,7 +1237,7 @@ _modinst_: @rm -rf $(MODLIB)/kernel @rm -f $(MODLIB)/source @mkdir -p $(MODLIB)/kernel - @ln -s `cd $(srctree) && /bin/pwd` $(MODLIB)/source + @ln -s $(abspath $(srctree)) $(MODLIB)/source @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \ rm -f $(MODLIB)/build ; \ ln -s $(CURDIR) $(MODLIB)/build ; \ @@ -1629,11 +1629,11 @@ image_name: # Clear a bunch of variables before executing the submake tools/: FORCE $(Q)mkdir -p $(objtree)/tools - $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/ + $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/ tools/%: FORCE $(Q)mkdir -p $(objtree)/tools - $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/ $* + $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(src)/tools/ $* # Single targets # --------------------------------------------------------------------------- diff --git a/scripts/gdb/linux/Makefile b/scripts/gdb/linux/Makefile index 8b00031f5349..ab3cfe727a4e 100644 --- a/scripts/gdb/linux/Makefile +++ b/scripts/gdb/linux/Makefile @@ -1,6 +1,6 @@ always := gdb-scripts -SRCTREE := $(shell cd $(srctree) && /bin/pwd) +SRCTREE := $(abspath $(srctree)) $(obj)/gdb-scripts: ifneq ($(KBUILD_SRC),) diff --git a/tools/power/cpupower/Makefile b/tools/power/cpupower/Makefile index d6e1c02ddcfe..4c5a481a850c 100644 --- a/tools/power/cpupower/Makefile +++ b/tools/power/cpupower/Makefile @@ -26,7 +26,7 @@ endif ifneq ($(OUTPUT),) # check that the output directory actually exists -OUTDIR := $(shell cd $(OUTPUT) && /bin/pwd) +OUTDIR := $(realpath $(OUTPUT)) $(if $(OUTDIR),, $(error output directory "$(OUTPUT)" does not exist)) endif diff --git a/tools/scripts/Makefile.include b/tools/scripts/Makefile.include index ccad8ce925e4..57a850978cef 100644 --- a/tools/scripts/Makefile.include +++ b/tools/scripts/Makefile.include @@ -1,7 +1,7 @@ ifneq ($(O),) ifeq ($(origin O), command line) - dummy := $(if $(shell test -d $(O) || echo $(O)),$(error O=$(O) does not exist),) - ABSOLUTE_O := $(shell cd $(O) ; pwd) + ABSOLUTE_O := $(realpath $(O)) + dummy := $(if $(ABSOLUTE_O),,$(error O=$(O) does not exist)) OUTPUT := $(ABSOLUTE_O)/$(if $(subdir),$(subdir)/) COMMAND_O := O=$(ABSOLUTE_O) ifeq ($(objtree),) @@ -12,7 +12,7 @@ endif # check that the output directory actually exists ifneq ($(OUTPUT),) -OUTDIR := $(shell cd $(OUTPUT) && /bin/pwd) +OUTDIR := $(realpath $(OUTPUT)) $(if $(OUTDIR),, $(error output directory "$(OUTPUT)" does not exist)) endif
Kbuild conventionally uses $(shell cd ... && /bin/pwd) idiom to get the absolute path of the directory because GNU Make 3.80, the minimal supported version at that time, did not support $(abspath ...) or $(realpath ...). Commit 37d69ee30808 ("docs: bump minimal GNU Make version to 3.81") dropped the GNU Make 3.80 support, so we are now allowed to use those make-builtin helpers. This conversion will provide better portability without relying on the pwd command or its location /bin/pwd. I am intentionally using $(realpath ...) instead $(abspath ...) in some places. The difference between the two is $(realpath ...) returns an empty string if the given path does not exist. It is convenient in places where we need to error-out if the makefile fails to create an output directory. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> --- Makefile | 12 ++++++------ scripts/gdb/linux/Makefile | 2 +- tools/power/cpupower/Makefile | 2 +- tools/scripts/Makefile.include | 6 +++--- 4 files changed, 11 insertions(+), 11 deletions(-)