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| author | Masahiro Yamada <masahiroy@kernel.org> | 2023-12-16 01:06:37 +0900 |
|---|---|---|
| committer | Masahiro Yamada <masahiroy@kernel.org> | 2023-12-29 22:25:21 +0900 |
| commit | 7beba04eb305393e3f8386390f25b4a9475f27f2 (patch) | |
| tree | 8e35c7f8a4676e4468ebb7587e660ab0ddcadc61 /Makefile | |
| parent | 8c88bc5b489e785c7ead94ce6fc3adb7f76e8715 (diff) | |
| download | lwn-7beba04eb305393e3f8386390f25b4a9475f27f2.tar.gz lwn-7beba04eb305393e3f8386390f25b4a9475f27f2.zip | |
kbuild: resolve symlinks for O= properly
Currently, Kbuild follows the logical chain of directories for the O=
option, just like 'cd' (or 'realpath --logical') does.
Example:
$ mkdir -p /tmp/a /tmp/x/y
$ ln -s /tmp/x/y /tmp/a/b
$ realpath /tmp/a/b/..
/tmp/x
$ realpath --logical /tmp/a/b/..
/tmp/a
$ make O=/tmp/a/b/.. defconfig
make[1]: Entering directory '/tmp/a'
[snip]
make[1]: Leaving directory '/tmp/a'
'make O=/tmp/a/b/.. defconfig' creates the kernel configuration in
/tmp/a instead of /tmp/x despite /tmp/a/b/.. resolves to /tmp/x.
This is because Kbuild internally uses the 'cd ... && pwd' for the
path resolution, but this behavior is not predictable for users.
Additionally, it is not consistent with how the Kbuild handles the
M= option or GNU Make works with 'make -C /tmp/a/b/..'.
Using the physical directory structure for the O= option seems more
reasonable.
The comment says "expand a shell special character '~'", but it has
already been expanded to the home directory in the command line.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
Diffstat (limited to 'Makefile')
| -rw-r--r-- | Makefile | 11 |
1 files changed, 4 insertions, 7 deletions
@@ -190,14 +190,11 @@ ifeq ("$(origin O)", "command line") endif ifneq ($(KBUILD_OUTPUT),) -# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot -# expand a shell special character '~'. We use a somewhat tedious way here. -abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd) -$(if $(abs_objtree),, \ - $(error failed to create output directory "$(KBUILD_OUTPUT)")) - +# $(realpath ...) gets empty if the path does not exist. Run 'mkdir -p' first. +$(shell mkdir -p "$(KBUILD_OUTPUT)") # $(realpath ...) resolves symlinks -abs_objtree := $(realpath $(abs_objtree)) +abs_objtree := $(realpath $(KBUILD_OUTPUT)) +$(if $(abs_objtree),,$(error failed to create output directory "$(KBUILD_OUTPUT)")) endif # ifneq ($(KBUILD_OUTPUT),) ifneq ($(words $(subst :, ,$(abs_srctree))), 1) |