| Message ID | 20240803125153.216030-1-gnurou@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Makefile: add $(srctree) to dependency of compile_commands.json target | expand |
On Sat, Aug 3, 2024 at 9:52 PM Alexandre Courbot <gnurou@gmail.com> wrote: > > When trying to build the compile_commands.json target from an external > module's directory, the following error is displayed: > > make[1]: *** No rule to make target 'scripts/clang-tools/gen_compile_commands.py', > needed by 'compile_commands.json'. Stop. Good catch. But, to reproduce this, O= option is also needed, right? e.g. $ make O=path/to/build/dir M=path/to/external/module/dir > This appears to be because gen_compile_commands.py is looked up using > relative path, which doesn't exist from the module's source tree. The phrase "appears to be ..." is somewhat modest. You can reword this to pin-point the first bad commit. For example: gen_compile_commands.py was previously looked up using a relative path to $(srctree), but commit b1992c3772e6 ("kbuild: use $(src) instead of $(srctree)/$(src) for source directory") stopped defining VPATH for external module builds. > Prefixing the dependency with $(srctree) fixes the problem. This needs back-porting. Please add this: Fixes: b1992c3772e6 ("kbuild: use $(src) instead of $(srctree)/$(src) for source directory") Thanks. > Signed-off-by: Alexandre Courbot <gnurou@gmail.com> > --- > Makefile | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/Makefile b/Makefile > index 8ad55d6e7b60..52d7dfe4212a 100644 > --- a/Makefile > +++ b/Makefile > @@ -1980,7 +1980,7 @@ nsdeps: modules > quiet_cmd_gen_compile_commands = GEN $@ > cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs)) > > -$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \ > +$(extmod_prefix)compile_commands.json: $(srctree)/scripts/clang-tools/gen_compile_commands.py \ > $(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \ > $(if $(CONFIG_MODULES), $(MODORDER)) FORCE > $(call if_changed,gen_compile_commands) > -- > 2.46.0 > -- Best Regards Masahiro Yamada
On Sat, Aug 3, 2024 at 10:47 PM Masahiro Yamada <masahiroy@kernel.org> wrote: > > On Sat, Aug 3, 2024 at 9:52 PM Alexandre Courbot <gnurou@gmail.com> wrote: > > > > When trying to build the compile_commands.json target from an external > > module's directory, the following error is displayed: > > > > make[1]: *** No rule to make target 'scripts/clang-tools/gen_compile_commands.py', > > needed by 'compile_commands.json'. Stop. > > > Good catch. > > But, to reproduce this, O= option is also needed, right? > > e.g. > > $ make O=path/to/build/dir M=path/to/external/module/dir I am building the module as follows: $ make -C ../linux/build M=$PWD modules compile_commands.json The kernel itself was built with O=build though. > > This appears to be because gen_compile_commands.py is looked up using > > relative path, which doesn't exist from the module's source tree. > > > The phrase "appears to be ..." is somewhat modest. > > > You can reword this to pin-point the first bad commit. > > > For example: > > gen_compile_commands.py was previously looked up using a relative path > to $(srctree), but commit b1992c3772e6 ("kbuild: use $(src) instead of > $(srctree)/$(src) for source directory") stopped defining VPATH for > external module builds. Thanks, that's much better. I should indeed have bisected to find the source of the regression. > > > > > Prefixing the dependency with $(srctree) fixes the problem. > > > > This needs back-porting. > > > Please add this: > > Fixes: b1992c3772e6 ("kbuild: use $(src) instead of $(srctree)/$(src) > for source directory") Done, and sent v2 as well. Thank you! Alex.
On Sun, Aug 4, 2024 at 2:51 PM Alexandre Courbot <gnurou@gmail.com> wrote: > > On Sat, Aug 3, 2024 at 10:47 PM Masahiro Yamada <masahiroy@kernel.org> wrote: > > > > On Sat, Aug 3, 2024 at 9:52 PM Alexandre Courbot <gnurou@gmail.com> wrote: > > > > > > When trying to build the compile_commands.json target from an external > > > module's directory, the following error is displayed: > > > > > > make[1]: *** No rule to make target 'scripts/clang-tools/gen_compile_commands.py', > > > needed by 'compile_commands.json'. Stop. > > > > > > Good catch. > > > > But, to reproduce this, O= option is also needed, right? > > > > e.g. > > > > $ make O=path/to/build/dir M=path/to/external/module/dir > > I am building the module as follows: > > $ make -C ../linux/build M=$PWD modules compile_commands.json OK, this is equivalent to the command I gave. You are building your external module against the kernel built in a separate output directory.
diff --git a/Makefile b/Makefile index 8ad55d6e7b60..52d7dfe4212a 100644 --- a/Makefile +++ b/Makefile @@ -1980,7 +1980,7 @@ nsdeps: modules quiet_cmd_gen_compile_commands = GEN $@ cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs)) -$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \ +$(extmod_prefix)compile_commands.json: $(srctree)/scripts/clang-tools/gen_compile_commands.py \ $(if $(KBUILD_EXTMOD),, vmlinux.a $(KBUILD_VMLINUX_LIBS)) \ $(if $(CONFIG_MODULES), $(MODORDER)) FORCE $(call if_changed,gen_compile_commands)
When trying to build the compile_commands.json target from an external module's directory, the following error is displayed: make[1]: *** No rule to make target 'scripts/clang-tools/gen_compile_commands.py', needed by 'compile_commands.json'. Stop. This appears to be because gen_compile_commands.py is looked up using relative path, which doesn't exist from the module's source tree. Prefixing the dependency with $(srctree) fixes the problem. Signed-off-by: Alexandre Courbot <gnurou@gmail.com> --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)